Merge branch 'main' into windows-dns-firewall

client/internal/acl/manager.go

@@ -11,6 +11,7 @@ import (
 	"time"
 
 	"github.com/hashicorp/go-multierror"
+	"github.com/mitchellh/hashstructure/v2"
 	log "github.com/sirupsen/logrus"
 
 	nberrors "github.com/netbirdio/netbird/client/errors"
@@ -30,11 +31,13 @@ type Manager interface {
 
 // DefaultManager uses firewall manager to handle
 type DefaultManager struct {
-	firewall       firewall.Manager
-	ipsetCounter   int
-	peerRulesPairs map[id.RuleID][]firewall.Rule
-	routeRules     map[id.RuleID]struct{}
-	mutex          sync.Mutex
+	firewall           firewall.Manager
+	ipsetCounter       int
+	peerRulesPairs     map[id.RuleID][]firewall.Rule
+	routeRules         map[id.RuleID]struct{}
+	previousConfigHash uint64
+	hasAppliedConfig   bool
+	mutex              sync.Mutex
 }
 
 func NewDefaultManager(fm firewall.Manager) *DefaultManager {
@@ -57,6 +60,23 @@ func (d *DefaultManager) ApplyFiltering(networkMap *mgmProto.NetworkMap, dnsRout
 		return
 	}
 
+	// Skip the full rebuild + flush when the inputs that drive the firewall
+	// state are byte-for-byte identical to the last successfully applied
+	// update. Management re-sends the same network map far more often than it
+	// actually changes (account-wide updates, peer meta churn), and rebuilding
+	// every peer/route ACL and flushing the firewall on every such sync is the
+	// dominant client-side cost when nothing changed. Mirrors the same guard the
+	// DNS server already uses (previousConfigHash). Only the fields ApplyFiltering
+	// consumes participate in the hash, so an unrelated map change cannot mask a
+	// real ACL change.
+	hash, err := d.firewallConfigHash(networkMap, dnsRouteFeatureFlag)
+	if err != nil {
+		log.Errorf("unable to hash firewall configuration, applying unconditionally: %v", err)
+	} else if d.hasAppliedConfig && d.previousConfigHash == hash {
+		log.Debugf("not applying the firewall configuration update as there is nothing new (hash: %d)", hash)
+		return
+	}
+
 	start := time.Now()
 	defer func() {
 		total := 0
@@ -70,13 +90,49 @@ func (d *DefaultManager) ApplyFiltering(networkMap *mgmProto.NetworkMap, dnsRout
 
 	d.applyPeerACLs(networkMap)
 
-	if err := d.applyRouteACLs(networkMap.RoutesFirewallRules, dnsRouteFeatureFlag); err != nil {
-		log.Errorf("Failed to apply route ACLs: %v", err)
+	routeErr := d.applyRouteACLs(networkMap.RoutesFirewallRules, dnsRouteFeatureFlag)
+	if routeErr != nil {
+		log.Errorf("Failed to apply route ACLs: %v", routeErr)
 	}
 
-	if err := d.firewall.Flush(); err != nil {
-		log.Error("failed to flush firewall rules: ", err)
+	flushErr := d.firewall.Flush()
+	if flushErr != nil {
+		log.Error("failed to flush firewall rules: ", flushErr)
 	}
+
+	// Only remember the hash once the firewall actually reflects this config.
+	// If applying or flushing failed, leave the previous hash untouched so the
+	// next (possibly identical) update is not skipped and gets a chance to
+	// reconcile the firewall state.
+	if err == nil && routeErr == nil && flushErr == nil {
+		d.previousConfigHash = hash
+		d.hasAppliedConfig = true
+	} else {
+		d.hasAppliedConfig = false
+	}
+}
+
+// firewallConfigHash hashes exactly the inputs ApplyFiltering uses to build the
+// firewall state, so an identical hash means an identical resulting ruleset.
+func (d *DefaultManager) firewallConfigHash(networkMap *mgmProto.NetworkMap, dnsRouteFeatureFlag bool) (uint64, error) {
+	return hashstructure.Hash(struct {
+		PeerRules           []*mgmProto.FirewallRule
+		PeerRulesIsEmpty    bool
+		RouteRules          []*mgmProto.RouteFirewallRule
+		RouteRulesIsEmpty   bool
+		DNSRouteFeatureFlag bool
+	}{
+		PeerRules:           networkMap.GetFirewallRules(),
+		PeerRulesIsEmpty:    networkMap.GetFirewallRulesIsEmpty(),
+		RouteRules:          networkMap.GetRoutesFirewallRules(),
+		RouteRulesIsEmpty:   networkMap.GetRoutesFirewallRulesIsEmpty(),
+		DNSRouteFeatureFlag: dnsRouteFeatureFlag,
+	}, hashstructure.FormatV2, &hashstructure.HashOptions{
+		ZeroNil:         true,
+		IgnoreZeroValue: true,
+		SlicesAsSets:    true,
+		UseStringer:     true,
+	})
 }
 
 func (d *DefaultManager) applyPeerACLs(networkMap *mgmProto.NetworkMap) {
@@ -88,13 +144,13 @@ func (d *DefaultManager) applyPeerACLs(networkMap *mgmProto.NetworkMap) {
 		log.Warn("this peer is connected to a NetBird Management service with an older version. Allowing all traffic from connected peers")
 		rules = append(rules,
 			&mgmProto.FirewallRule{
-				PeerIP:    "0.0.0.0",
+				PeerIP:    "0.0.0.0", //nolint:staticcheck
 				Direction: mgmProto.RuleDirection_IN,
 				Action:    mgmProto.RuleAction_ACCEPT,
 				Protocol:  mgmProto.RuleProtocol_ALL,
 			},
 			&mgmProto.FirewallRule{
-				PeerIP:    "0.0.0.0",
+				PeerIP:    "0.0.0.0", //nolint:staticcheck
 				Direction: mgmProto.RuleDirection_OUT,
 				Action:    mgmProto.RuleAction_ACCEPT,
 				Protocol:  mgmProto.RuleProtocol_ALL,
@@ -351,7 +407,6 @@ func (d *DefaultManager) getRuleGroupingSelector(rule *mgmProto.FirewallRule) st
 	return fmt.Sprintf("%v:%v:%v:%s:%v", strconv.Itoa(int(rule.Direction)), rule.Action, rule.Protocol, rule.Port, rule.PortInfo)
 }
 
-
 // extractRuleIP extracts the peer IP from a firewall rule.
 // If sourcePrefixes is populated (new management), decode the first entry and use its address.
 // Otherwise fall back to the deprecated PeerIP string field (old management).

client/internal/acl/manager_test.go

@@ -1,12 +1,13 @@
 package acl
 
 import (
+	"fmt"
 	"net/netip"
 	"testing"
 
-	"github.com/golang/mock/gomock"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.uber.org/mock/gomock"
 
 	"github.com/netbirdio/netbird/client/firewall"
 	"github.com/netbirdio/netbird/client/iface"
@@ -86,7 +87,7 @@ func TestDefaultManager(t *testing.T) {
 		networkMap.FirewallRules = append(
 			networkMap.FirewallRules,
 			&mgmProto.FirewallRule{
-				PeerIP:    "10.93.0.3",
+				PeerIP:    "10.93.0.3", //nolint:staticcheck
 				Direction: mgmProto.RuleDirection_IN,
 				Action:    mgmProto.RuleAction_DROP,
 				Protocol:  mgmProto.RuleProtocol_ICMP,
@@ -485,3 +486,149 @@ func TestPortInfoEmpty(t *testing.T) {
 		})
 	}
 }
+
+// TestApplyFilteringSkipsUnchangedConfig verifies that an identical network map
+// re-applied is recognized as a no-op (hash unchanged), while a real change to
+// any firewall-relevant input forces a re-apply (hash changes). This is the
+// guard that prevents a full ruleset rebuild + flush on every redundant sync.
+func TestApplyFilteringSkipsUnchangedConfig(t *testing.T) {
+	t.Setenv("NB_WG_KERNEL_DISABLED", "true")
+	t.Setenv(firewall.EnvForceUserspaceFirewall, "true")
+
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	ifaceMock := mocks.NewMockIFaceMapper(ctrl)
+	ifaceMock.EXPECT().IsUserspaceBind().Return(true).AnyTimes()
+	ifaceMock.EXPECT().SetFilter(gomock.Any())
+	network := netip.MustParsePrefix("172.0.0.1/32")
+	ifaceMock.EXPECT().Name().Return("lo").AnyTimes()
+	ifaceMock.EXPECT().Address().Return(wgaddr.Address{
+		IP:      network.Addr(),
+		Network: network,
+	}).AnyTimes()
+	ifaceMock.EXPECT().GetWGDevice().Return(nil).AnyTimes()
+
+	fw, err := firewall.NewFirewall(ifaceMock, nil, flowLogger, false, iface.DefaultMTU)
+	require.NoError(t, err)
+	defer func() {
+		require.NoError(t, fw.Close(nil))
+	}()
+
+	acl := NewDefaultManager(fw)
+
+	networkMap := &mgmProto.NetworkMap{
+		FirewallRules: []*mgmProto.FirewallRule{
+			{
+				PeerIP:    "10.93.0.1",
+				Direction: mgmProto.RuleDirection_IN,
+				Action:    mgmProto.RuleAction_ACCEPT,
+				Protocol:  mgmProto.RuleProtocol_TCP,
+				Port:      "22",
+			},
+		},
+		FirewallRulesIsEmpty: false,
+	}
+
+	acl.ApplyFiltering(networkMap, false)
+	require.True(t, acl.hasAppliedConfig, "config should be marked applied after first apply")
+	firstHash := acl.previousConfigHash
+	require.NotZero(t, firstHash)
+
+	// Re-applying the identical map must not change the recorded hash: the
+	// expensive rebuild path was skipped.
+	acl.ApplyFiltering(networkMap, false)
+	assert.Equal(t, firstHash, acl.previousConfigHash,
+		"identical re-apply must be a no-op (hash unchanged)")
+
+	// A real change must produce a different hash and re-apply.
+	networkMap.FirewallRules[0].Action = mgmProto.RuleAction_DROP
+	acl.ApplyFiltering(networkMap, false)
+	assert.NotEqual(t, firstHash, acl.previousConfigHash,
+		"changing a rule's action must force a re-apply (hash changed)")
+
+	// The dnsRouteFeatureFlag also participates in the hash.
+	changedHash := acl.previousConfigHash
+	acl.ApplyFiltering(networkMap, true)
+	assert.NotEqual(t, changedHash, acl.previousConfigHash,
+		"flipping dnsRouteFeatureFlag must force a re-apply (hash changed)")
+}
+
+func buildNetworkMap(peerRules, routeRules int) *mgmProto.NetworkMap {
+	nm := &mgmProto.NetworkMap{
+		FirewallRulesIsEmpty:       peerRules == 0,
+		RoutesFirewallRulesIsEmpty: routeRules == 0,
+	}
+	for i := range peerRules {
+		nm.FirewallRules = append(nm.FirewallRules, &mgmProto.FirewallRule{
+			PeerIP:    fmt.Sprintf("10.%d.%d.%d", i>>16&0xff, i>>8&0xff, i&0xff), //nolint:staticcheck
+			Direction: mgmProto.RuleDirection_IN,
+			Action:    mgmProto.RuleAction_ACCEPT,
+			Protocol:  mgmProto.RuleProtocol_TCP,
+			Port:      fmt.Sprintf("%d", 1024+i%64511),
+		})
+	}
+	for i := range routeRules {
+		nm.RoutesFirewallRules = append(nm.RoutesFirewallRules, &mgmProto.RouteFirewallRule{
+			Destination:  fmt.Sprintf("192.168.%d.0/24", i%256),
+			SourceRanges: []string{fmt.Sprintf("10.0.%d.0/24", i%256)},
+			Action:       mgmProto.RuleAction_ACCEPT,
+			Protocol:     mgmProto.RuleProtocol_ALL,
+		})
+	}
+	return nm
+}
+
+func BenchmarkFirewallConfigHash_Small(b *testing.B) {
+	d := &DefaultManager{}
+	nm := buildNetworkMap(10, 5)
+	b.ResetTimer()
+	for b.Loop() {
+		_, _ = d.firewallConfigHash(nm, false)
+	}
+}
+
+func BenchmarkFirewallConfigHash_Medium(b *testing.B) {
+	d := &DefaultManager{}
+	nm := buildNetworkMap(100, 50)
+	b.ResetTimer()
+	for b.Loop() {
+		_, _ = d.firewallConfigHash(nm, false)
+	}
+}
+
+func BenchmarkFirewallConfigHash_Large(b *testing.B) {
+	d := &DefaultManager{}
+	nm := buildNetworkMap(1000, 200)
+	b.ResetTimer()
+	for b.Loop() {
+		_, _ = d.firewallConfigHash(nm, false)
+	}
+}
+
+// TestFirewallConfigHashDeterministic verifies the hash is stable for equal
+// inputs and order-independent for the rule slices (management does not
+// guarantee rule order).
+func TestFirewallConfigHashDeterministic(t *testing.T) {
+	d := &DefaultManager{}
+
+	nm1 := &mgmProto.NetworkMap{
+		FirewallRules: []*mgmProto.FirewallRule{
+			{PeerIP: "10.0.0.1", Direction: mgmProto.RuleDirection_IN, Action: mgmProto.RuleAction_ACCEPT, Protocol: mgmProto.RuleProtocol_TCP, Port: "22"},
+			{PeerIP: "10.0.0.2", Direction: mgmProto.RuleDirection_IN, Action: mgmProto.RuleAction_DROP, Protocol: mgmProto.RuleProtocol_TCP, Port: "80"},
+		},
+	}
+	// Same rules, reversed order.
+	nm2 := &mgmProto.NetworkMap{
+		FirewallRules: []*mgmProto.FirewallRule{
+			nm1.FirewallRules[1],
+			nm1.FirewallRules[0],
+		},
+	}
+
+	h1, err := d.firewallConfigHash(nm1, false)
+	require.NoError(t, err)
+	h2, err := d.firewallConfigHash(nm2, false)
+	require.NoError(t, err)
+	assert.Equal(t, h1, h2, "hash must be order-independent for rule slices")
+}

client/internal/acl/mocks/iface_mapper.go

@@ -7,7 +7,7 @@ package mocks
 import (
 	reflect "reflect"
 
-	gomock "github.com/golang/mock/gomock"
+	gomock "go.uber.org/mock/gomock"
 	wgdevice "golang.zx2c4.com/wireguard/device"
 
 	"github.com/netbirdio/netbird/client/iface/device"

client/internal/auth/auth.go

@@ -3,6 +3,7 @@ package auth
 import (
 	"context"
 	"net/url"
+	"strings"
 	"sync"
 	"time"
 
@@ -21,6 +22,25 @@ import (
 	mgmProto "github.com/netbirdio/netbird/shared/management/proto"
 )
 
+// peerLoginExpiredMsg is the exact phrase the management server returns
+// when a previously SSO-enrolled peer's login has expired. Sourced from
+// shared/management/status/error.go (NewPeerLoginExpiredError). Matched
+// by substring so a future server-side rewording that keeps the phrase
+// still triggers the friendly fallback in Login().
+const peerLoginExpiredMsg = "peer login has expired"
+
+// errSetupKeyOnSSOExpiredPeer replaces the raw management error when the
+// user runs `netbird login -k <setup-key>` against a peer that was
+// originally enrolled via SSO. Wrapped in a PermissionDenied gRPC status
+// so callers' existing isPermissionDenied / isAuthError checks still
+// classify it correctly (early-exit from retry backoff, StatusNeedsLogin
+// in the server state machine).
+var errSetupKeyOnSSOExpiredPeer = status.Error(
+	codes.PermissionDenied,
+	"this peer was originally enrolled via SSO and its session has expired. "+
+		"Setup keys can only enrol new peers — run `netbird up` (interactive SSO) to re-login.",
+)
+
 // Auth manages authentication operations with the management server
 // It maintains a long-lived connection and automatically handles reconnection with backoff
 type Auth struct {
@@ -118,26 +138,37 @@ func (a *Auth) IsSSOSupported(ctx context.Context) (bool, error) {
 
 // GetOAuthFlow returns an OAuth flow (PKCE or Device) using the existing management connection
 // This avoids creating a new connection to the management server
-func (a *Auth) GetOAuthFlow(ctx context.Context, forceDeviceAuth bool) (OAuthFlow, error) {
+func (a *Auth) GetOAuthFlow(ctx context.Context, forceDeviceAuth bool, hint string) (OAuthFlow, error) {
 	var flow OAuthFlow
-	var err error
 
-	err = a.withRetry(ctx, func(client *mgm.GrpcClient) error {
+	err := a.withRetry(ctx, func(client *mgm.GrpcClient) error {
 		if forceDeviceAuth {
-			flow, err = a.getDeviceFlow(client)
-			return err
+			deviceFlow, err := a.getDeviceFlow(client)
+			if err != nil {
+				return err
+			}
+			deviceFlow.SetLoginHint(hint)
+			flow = deviceFlow
+			return nil
 		}
 
 		// Try PKCE flow first
-		flow, err = a.getPKCEFlow(client)
+		pkceFlow, err := a.getPKCEFlow(client)
 		if err != nil {
 			// If PKCE not supported, try Device flow
 			if s, ok := status.FromError(err); ok && (s.Code() == codes.NotFound || s.Code() == codes.Unimplemented) {
-				flow, err = a.getDeviceFlow(client)
-				return err
+				deviceFlow, err := a.getDeviceFlow(client)
+				if err != nil {
+					return err
+				}
+				deviceFlow.SetLoginHint(hint)
+				flow = deviceFlow
+				return nil
 			}
 			return err
 		}
+		pkceFlow.SetLoginHint(hint)
+		flow = pkceFlow
 		return nil
 	})
 
@@ -184,6 +215,15 @@ func (a *Auth) Login(ctx context.Context, setupKey string, jwtToken string) (err
 			log.Debugf("peer registration required")
 			_, err = a.registerPeer(client, ctx, setupKey, jwtToken, pubSSHKey)
 			if err != nil {
+				// The peer pub-key is already on file with the management
+				// server (originally enrolled via SSO) and the session has
+				// expired. The setup-key path can only enrol new peers, so
+				// retrying with -k will keep failing. Replace the raw mgm
+				// message with an actionable hint that tells the user to
+				// re-authenticate via SSO instead.
+				if setupKey != "" && jwtToken == "" && isPeerLoginExpired(err) {
+					err = errSetupKeyOnSSOExpiredPeer
+				}
 				isAuthError = isPermissionDenied(err)
 				return err
 			}
@@ -322,7 +362,7 @@ func (a *Auth) setSystemInfoFlags(info *system.Info) {
 		a.config.BlockLANAccess,
 		a.config.BlockInbound,
 		a.config.DisableIPv6,
-		a.config.LazyConnectionEnabled,
+		a.config.SyncMessageVersion,
 		a.config.EnableSSHRoot,
 		a.config.EnableSSHSFTP,
 		a.config.EnableSSHLocalPortForwarding,
@@ -474,3 +514,16 @@ func isLoginNeeded(err error) bool {
 func isRegistrationNeeded(err error) bool {
 	return isPermissionDenied(err)
 }
+
+// isPeerLoginExpired reports whether err is the management server's
+// "peer login has expired" PermissionDenied response. Used by Login to
+// detect the case where the caller passed a setup-key but the peer is
+// actually an SSO-enrolled record whose session needs refreshing — the
+// setup-key path cannot help there.
+func isPeerLoginExpired(err error) bool {
+	if !isPermissionDenied(err) {
+		return false
+	}
+	s, _ := status.FromError(err)
+	return strings.Contains(s.Message(), peerLoginExpiredMsg)
+}

client/internal/auth/auth_test.go

@@ -0,0 +1,80 @@
+package auth
+
+import (
+	"errors"
+	"strings"
+	"testing"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+func TestIsPeerLoginExpired(t *testing.T) {
+	cases := []struct {
+		name string
+		err  error
+		want bool
+	}{
+		{
+			name: "nil",
+			err:  nil,
+			want: false,
+		},
+		{
+			name: "plain error (not a gRPC status)",
+			err:  errors.New("network read: connection reset"),
+			want: false,
+		},
+		{
+			name: "PermissionDenied with different message",
+			err:  status.Error(codes.PermissionDenied, "user is blocked"),
+			want: false,
+		},
+		{
+			name: "Unauthenticated with the expected phrase",
+			// Wrong status code — must still return false.
+			err:  status.Error(codes.Unauthenticated, "peer login has expired, please log in once more"),
+			want: false,
+		},
+		{
+			name: "exact server message",
+			err:  status.Error(codes.PermissionDenied, "peer login has expired, please log in once more"),
+			want: true,
+		},
+		{
+			name: "phrase as substring",
+			// Future-proofing: if mgm reworords but keeps the phrase,
+			// the friendly fallback must still kick in.
+			err:  status.Error(codes.PermissionDenied, "session refused: peer login has expired (account=foo)"),
+			want: true,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := isPeerLoginExpired(tc.err); got != tc.want {
+				t.Fatalf("isPeerLoginExpired(%v) = %v, want %v", tc.err, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestErrSetupKeyOnSSOExpiredPeer(t *testing.T) {
+	// Sentinel must surface as PermissionDenied so the upstream
+	// isPermissionDenied / isAuthError checks classify it correctly
+	// (short-circuit retry backoff, set StatusNeedsLogin).
+	if !isPermissionDenied(errSetupKeyOnSSOExpiredPeer) {
+		t.Fatalf("errSetupKeyOnSSOExpiredPeer must be a PermissionDenied gRPC error")
+	}
+
+	// Message must actually mention SSO and `netbird up` so it is
+	// actionable for the end user. Loose substring checks keep the
+	// test resilient to copy edits.
+	s, _ := status.FromError(errSetupKeyOnSSOExpiredPeer)
+	msg := strings.ToLower(s.Message())
+	for _, want := range []string{"sso", "netbird up"} {
+		if !strings.Contains(msg, want) {
+			t.Errorf("sentinel message should contain %q, got %q", want, s.Message())
+		}
+	}
+}

client/internal/auth/device_flow.go

@@ -259,12 +259,18 @@ func (d *DeviceAuthorizationFlow) WaitToken(ctx context.Context, info AuthFlowIn
 	ticker := time.NewTicker(interval)
 	defer ticker.Stop()
 
+	log.Infof("device flow: waiting for user authorization, polling token endpoint every %s, code expires in %s", interval, timeout)
+
+	start := time.Now()
+	polls := 0
+
 	for {
 		select {
 		case <-waitCtx.Done():
 			return TokenInfo{}, waitCtx.Err()
 		case <-ticker.C:
 
+			polls++
 			tokenResponse, err := d.requestToken(info)
 			if err != nil {
 				return TokenInfo{}, fmt.Errorf("parsing token response failed with error: %v", err)
@@ -272,10 +278,12 @@ func (d *DeviceAuthorizationFlow) WaitToken(ctx context.Context, info AuthFlowIn
 
 			if tokenResponse.Error != "" {
 				if tokenResponse.Error == "authorization_pending" {
+					log.Tracef("device flow: authorization still pending after poll %d", polls)
 					continue
 				} else if tokenResponse.Error == "slow_down" {
 					interval += (3 * time.Second)
 					ticker.Reset(interval)
+					log.Infof("device flow: IdP requested slow_down, polling interval increased to %s", interval)
 					continue
 				}
 
@@ -291,11 +299,12 @@ func (d *DeviceAuthorizationFlow) WaitToken(ctx context.Context, info AuthFlowIn
 				UseIDToken:   d.providerConfig.UseIDToken,
 			}
 
-			err = isValidAccessToken(tokenInfo.GetTokenToUse(), d.providerConfig.Audience)
+			err = validateTokenAudience(tokenInfo.GetTokenToUse(), d.providerConfig.Audience)
 			if err != nil {
 				return TokenInfo{}, fmt.Errorf("validate access token failed with error: %v", err)
 			}
 
+			log.Infof("device flow: user authorization confirmed after %d polls in %s", polls, time.Since(start).Round(time.Second))
 			return tokenInfo, err
 		}
 	}

client/internal/auth/oauth.go

@@ -97,9 +97,7 @@ func authenticateWithPKCEFlow(ctx context.Context, config *profilemanager.Config
 		return nil, fmt.Errorf("getting pkce authorization flow info failed with error: %v", err)
 	}
 
-	if hint != "" {
-		pkceFlowInfo.SetLoginHint(hint)
-	}
+	pkceFlowInfo.SetLoginHint(hint)
 
 	return pkceFlowInfo, nil
 }
@@ -127,9 +125,7 @@ func authenticateWithDeviceCodeFlow(ctx context.Context, config *profilemanager.
 		}
 	}
 
-	if hint != "" {
-		deviceFlowInfo.SetLoginHint(hint)
-	}
+	deviceFlowInfo.SetLoginHint(hint)
 
 	return deviceFlowInfo, nil
 }

client/internal/auth/pending_flow.go

@@ -0,0 +1,89 @@
+package auth
+
+import (
+	"context"
+	"sync"
+	"time"
+)
+
+// PendingFlow stores an in-progress OAuth flow between the RPC that
+// initiates it (returns the verification URI to the UI) and the RPC
+// that waits for the user to complete it. The flow handle, the
+// device-code info, and the absolute expiry are kept together so the
+// waiting RPC can validate the device code and reuse the same flow.
+//
+// PendingFlow is safe for concurrent use; callers must not access the
+// stored fields directly.
+type PendingFlow struct {
+	mu         sync.Mutex
+	flow       OAuthFlow
+	info       AuthFlowInfo
+	expiresAt  time.Time
+	waitCancel context.CancelFunc
+}
+
+// NewPendingFlow returns an empty PendingFlow ready to be populated by Set.
+func NewPendingFlow() *PendingFlow {
+	return &PendingFlow{}
+}
+
+// Set stores the flow and its authorization info, computing the absolute
+// expiry from info.ExpiresIn (seconds, as returned by the IdP).
+func (p *PendingFlow) Set(flow OAuthFlow, info AuthFlowInfo) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.flow = flow
+	p.info = info
+	p.expiresAt = time.Now().Add(time.Duration(info.ExpiresIn) * time.Second)
+}
+
+// Get returns the stored flow, info, and whether a flow is currently
+// pending. Returns (nil, zero, false) after Clear or before Set.
+func (p *PendingFlow) Get() (OAuthFlow, AuthFlowInfo, bool) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.flow == nil {
+		return nil, AuthFlowInfo{}, false
+	}
+	return p.flow, p.info, true
+}
+
+// ExpiresAt returns the absolute expiry of the pending flow. Returns
+// the zero time when no flow is pending.
+func (p *PendingFlow) ExpiresAt() time.Time {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	return p.expiresAt
+}
+
+// SetWaitCancel records the cancel function for the goroutine currently
+// blocked in WaitToken so a new RequestAuth can preempt it.
+func (p *PendingFlow) SetWaitCancel(cancel context.CancelFunc) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.waitCancel = cancel
+}
+
+// CancelWait invokes and clears the stored wait-cancel, if any. Safe to
+// call when no wait is in progress.
+func (p *PendingFlow) CancelWait() {
+	p.mu.Lock()
+	cancel := p.waitCancel
+	p.waitCancel = nil
+	p.mu.Unlock()
+	if cancel != nil {
+		cancel()
+	}
+}
+
+// Clear resets the pending flow to empty. Any stored wait-cancel is
+// dropped without being invoked — call CancelWait first if the waiting
+// goroutine must be stopped.
+func (p *PendingFlow) Clear() {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	p.flow = nil
+	p.info = AuthFlowInfo{}
+	p.expiresAt = time.Time{}
+	p.waitCancel = nil
+}

client/internal/auth/pkce_flow.go

@@ -188,6 +188,8 @@ func (p *PKCEAuthorizationFlow) WaitToken(ctx context.Context, info AuthFlowInfo
 	waitCtx, cancel := context.WithTimeout(ctx, timeout)
 	defer cancel()
 
+	log.Infof("pkce flow: waiting for authorization callback on %s, timeout %s", p.oAuthConfig.RedirectURL, timeout)
+
 	tokenChan := make(chan *oauth2.Token, 1)
 	errChan := make(chan error, 1)
 
@@ -221,6 +223,7 @@ func (p *PKCEAuthorizationFlow) WaitToken(ctx context.Context, info AuthFlowInfo
 func (p *PKCEAuthorizationFlow) startServer(server *http.Server, tokenChan chan<- *oauth2.Token, errChan chan<- error) {
 	mux := http.NewServeMux()
 	mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
+		log.Infof("pkce flow: received authorization callback from IdP")
 		cert := p.providerConfig.ClientCertPair
 		if cert != nil {
 			tr := &http.Transport{
@@ -271,11 +274,18 @@ func (p *PKCEAuthorizationFlow) handleRequest(req *http.Request) (*oauth2.Token,
 		return nil, fmt.Errorf("authentication failed: missing code")
 	}
 
-	return p.oAuthConfig.Exchange(
+	exchangeStart := time.Now()
+	token, err := p.oAuthConfig.Exchange(
 		req.Context(),
 		code,
 		oauth2.SetAuthURLParam("code_verifier", p.codeVerifier),
 	)
+	if err != nil {
+		return nil, err
+	}
+
+	log.Infof("pkce flow: authorization code exchanged for token in %s", time.Since(exchangeStart).Round(time.Millisecond))
+	return token, nil
 }
 
 func (p *PKCEAuthorizationFlow) parseOAuthToken(token *oauth2.Token) (TokenInfo, error) {
@@ -296,7 +306,7 @@ func (p *PKCEAuthorizationFlow) parseOAuthToken(token *oauth2.Token) (TokenInfo,
 		audience = p.providerConfig.ClientID
 	}
 
-	if err := isValidAccessToken(tokenInfo.GetTokenToUse(), audience); err != nil {
+	if err := validateTokenAudience(tokenInfo.GetTokenToUse(), audience); err != nil {
 		return TokenInfo{}, fmt.Errorf("authentication failed: invalid access token - %w", err)
 	}
 
@@ -310,6 +320,11 @@ func (p *PKCEAuthorizationFlow) parseOAuthToken(token *oauth2.Token) (TokenInfo,
 	return tokenInfo, nil
 }
 
+// parseEmailFromIDToken extracts the email (or name) claim from an ID token
+// without verifying its signature. The value is best-effort and used only as a
+// UX convenience (login hint prefill and display); it never drives an
+// authorization decision. The authoritative identity is established server-side
+// from the signature-verified token.
 func parseEmailFromIDToken(token string) (string, error) {
 	parts := strings.Split(token, ".")
 	if len(parts) < 2 {

client/internal/auth/sessionwatch/event.go

@@ -0,0 +1,82 @@
+package sessionwatch
+
+import (
+	"strconv"
+	"time"
+)
+
+// internal event kinds are no longer exposed: the watcher drives the Sink
+// directly (NotifyStateChange on deadline change/clear, PublishEvent at
+// each warning lead). Tests use a mock Sink to observe what the watcher
+// emits.
+
+// Metadata keys attached by the daemon to session-warning SystemEvents.
+// The UI tray reads these to build a locale-aware notification without
+// relying on the daemon's locale-less UserMessage string, and to
+// disambiguate the T-WarningLead notification from the T-FinalWarningLead
+// fallback that auto-opens the SessionAboutToExpire dialog.
+const (
+	// MetaSessionWarning is set to "true" on both warning events (T-10 and
+	// T-2) so the UI can detect a session-warning SystemEvent without
+	// matching on the message text. Use MetaSessionFinal to distinguish
+	// the two.
+	MetaSessionWarning = "session_warning"
+	// MetaSessionFinal is set to "true" on the T-FinalWarningLead event
+	// only. Consumers that need to auto-open the SessionAboutToExpire
+	// dialog gate on this; T-WarningLead events leave the field unset.
+	MetaSessionFinal = "session_final_warning"
+	// MetaSessionExpiresAt carries the absolute UTC deadline encoded with
+	// FormatExpiresAt; consumers must decode with ParseExpiresAt so a
+	// future format change stays a single edit.
+	MetaSessionExpiresAt = "session_expires_at"
+	// MetaSessionLeadMinutes carries the lead in whole minutes (WarningLead
+	// for the T-10 event, FinalWarningLead for the T-2 event) so the UI
+	// can show "expires in ~N minutes" without hardcoding either constant.
+	MetaSessionLeadMinutes = "lead_minutes"
+	// MetaSessionDeadlineRejected is attached to the ERROR/AUTHENTICATION
+	// SystemEvent the daemon emits when it discards a deadline from the
+	// management server (pre-epoch, too far in the future, or past the
+	// clock-skew tolerance). The value is the rejection reason string.
+	// userMessage is left empty; the UI detects the event via this key
+	// and builds a localized notification — same pattern as the session
+	// warnings above.
+	MetaSessionDeadlineRejected = "session_deadline_rejected"
+)
+
+// expiresAtLayout is the wire format used for MetaSessionExpiresAt.
+// Producer and consumers both go through FormatExpiresAt/ParseExpiresAt
+// so this layout stays a single source of truth.
+const expiresAtLayout = time.RFC3339
+
+// FormatExpiresAt encodes a deadline for MetaSessionExpiresAt. Always
+// emits UTC so a consumer in another timezone reads the same wall-clock
+// deadline.
+func FormatExpiresAt(t time.Time) string {
+	return t.UTC().Format(expiresAtLayout)
+}
+
+// ParseExpiresAt decodes the MetaSessionExpiresAt value back to a UTC
+// time. Returns an error when the field is empty or malformed; the
+// caller decides whether to fall back (zero value) or propagate.
+func ParseExpiresAt(s string) (time.Time, error) {
+	t, err := time.Parse(expiresAtLayout, s)
+	if err != nil {
+		return time.Time{}, err
+	}
+	return t.UTC(), nil
+}
+
+// FormatLeadMinutes encodes a lead duration for MetaSessionLeadMinutes
+// as the integer count of whole minutes. Sub-minute residuals are
+// truncated — the field is informational ("expires in ~N minutes") and
+// fractional minutes don't change what the UI displays.
+func FormatLeadMinutes(d time.Duration) string {
+	return strconv.Itoa(int(d / time.Minute))
+}
+
+// ParseLeadMinutes decodes a MetaSessionLeadMinutes value. Returns 0
+// and the parse error for malformed input; consumers that prefer a
+// silent fallback can simply ignore the error.
+func ParseLeadMinutes(s string) (int, error) {
+	return strconv.Atoi(s)
+}

client/internal/auth/sessionwatch/watcher.go

@@ -0,0 +1,382 @@
+// Package sessionwatch tracks the SSO session expiry deadline that the
+// management server publishes via LoginResponse / SyncResponse and fires
+// two warning events at fixed lead times before expiry: an interactive
+// T-WarningLead notification and a dismiss-gated T-FinalWarningLead
+// fallback dialog.
+//
+// The watcher is idempotent: Update may be called as often as the network
+// map snapshots arrive. Repeating the same deadline is a no-op; a new
+// deadline reschedules the timers and arms a fresh warning cycle.
+//
+// Warning firing is edge-detected. Each unique deadline value fires each
+// warning callback at most once.
+package sessionwatch
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+
+	cProto "github.com/netbirdio/netbird/client/proto"
+)
+
+const (
+	maxPastHorizon = 30 * 24 * time.Hour
+
+	// maxDeadlineHorizon caps how far in the future an accepted deadline
+	// can sit. A timestamp beyond this is almost certainly a protocol
+	// glitch, and silently arming a 100-year timer would hide the bug.
+	maxDeadlineHorizon = 10 * 365 * 24 * time.Hour
+
+	// WarningLead is how far before expiry the first (interactive)
+	// warning fires. Drives the T-10 OS notification with
+	// Extend/Dismiss actions.
+	WarningLead = 10 * time.Minute
+
+	// FinalWarningLead is how far before expiry the fallback final
+	// warning fires. Drives the auto-opened SessionAboutToExpire dialog,
+	// but only when the user has not dismissed the T-WarningLead warning
+	// for the same deadline. Must be strictly less than WarningLead.
+	FinalWarningLead = 2 * time.Minute
+)
+
+var (
+	// ErrDeadlineBeforeEpoch is returned by Update when the supplied
+	// deadline pre-dates 1970-01-01.
+	ErrDeadlineBeforeEpoch = errors.New("session deadline before unix epoch")
+
+	// ErrDeadlineTooFarFuture is returned by Update when the supplied
+	// deadline is more than maxDeadlineHorizon in the future.
+	ErrDeadlineTooFarFuture = errors.New("session deadline too far in the future")
+
+	// ErrDeadlineInPast is returned by Update when the supplied deadline
+	// is more than maxPastHorizon in the past.
+	ErrDeadlineInPast = errors.New("session deadline in the past")
+)
+
+// StatusRecorder is the side-effect surface the watcher drives on every
+// state transition. Production wires this to peer.Status (SetSessionExpiresAt
+// for deadline change/clear, PublishEvent for the two warnings); tests pass
+// a fake recorder so the same surface is observable without an engine.
+//
+// While the watcher runs, it owns the deadline propagated to the recorder:
+// every set, clear and sanity-check rejection routes the value through
+// SetSessionExpiresAt, so the SubscribeStatus snapshot the UI reads can
+// never drift from the watcher's timer state. (SetSessionExpiresAt fans
+// out its own state-change notification, so no separate notify is needed.)
+// The recorder is server-scoped and outlives this engine-scoped watcher;
+// Close deliberately leaves the recorder value in place so transient engine
+// restarts don't blank it — the client run loop clears it on real teardown.
+//
+// PublishEvent's signature mirrors peer.Status.PublishEvent: the watcher
+// composes the metadata internally so the wire format (MetaSession*) is
+// owned by sessionwatch, not the caller.
+type StatusRecorder interface {
+	SetSessionExpiresAt(deadline time.Time)
+	PublishEvent(
+		severity cProto.SystemEvent_Severity,
+		category cProto.SystemEvent_Category,
+		message string,
+		userMessage string,
+		metadata map[string]string,
+	)
+}
+
+// Watcher observes the latest session deadline and fires two warnings
+// before it expires: the interactive T-WarningLead notification, and the
+// fallback T-FinalWarningLead dialog (suppressed when the user dismissed
+// the first one for the same deadline). Safe for concurrent use.
+type Watcher struct {
+	lead      time.Duration
+	finalLead time.Duration
+
+	mu           sync.Mutex
+	current      time.Time
+	timer        *time.Timer
+	finalTimer   *time.Timer
+	firedAt      time.Time // deadline value the T-WarningLead callback last fired against
+	finalFiredAt time.Time // deadline value the T-FinalWarningLead callback last fired against
+	dismissedAt  time.Time // deadline value the user dismissed via Dismiss(); gates fireFinal
+	closed       bool
+	recorder     StatusRecorder
+}
+
+// New returns a watcher with the package defaults WarningLead and
+// FinalWarningLead. Pass nil for recorder to silence side effects (handy
+// in unit tests that exercise sanity checks without observing the publish
+// path).
+func New(recorder StatusRecorder) *Watcher {
+	return NewWithLeads(WarningLead, FinalWarningLead, recorder)
+}
+
+// NewWithLeads returns a watcher with custom lead times. Useful for tests.
+// final must be strictly less than lead; otherwise both timers fire in the
+// wrong order or simultaneously and the UI flow breaks. A zero final lead
+// disables the final-warning timer entirely (see armTimerLocked) so a
+// millisecond-scale deadline doesn't flush both timers in one tick.
+func NewWithLeads(lead, final time.Duration, recorder StatusRecorder) *Watcher {
+	return &Watcher{
+		lead:      lead,
+		finalLead: final,
+		recorder:  recorder,
+	}
+}
+
+// Update sets the latest deadline. Pass the zero time to clear (e.g. when
+// a Sync push from the server omits the field because login expiration
+// was disabled).
+//
+// Same-value updates are no-ops. A different non-zero value cancels any
+// pending timer, resets the "already fired" guards, and — when the
+// deadline lies in the future — arms fresh warning timers. A deadline
+// already in the past (within maxPastHorizon) is recorded as-is with no
+// timers: the session has expired and consumers render it that way.
+//
+// Returns one of the sentinel Err* values when the deadline fails the
+// sanity checks (pre-epoch, far future, or past beyond maxPastHorizon).
+// In every error case the watcher first clears its state so it stays
+// consistent with what the caller will push into its other sinks (e.g.
+// applySessionDeadline forces a zero deadline into the status recorder
+// after a non-nil error).
+func (w *Watcher) Update(deadline time.Time) error {
+	w.mu.Lock()
+	if w.closed {
+		w.mu.Unlock()
+		return nil
+	}
+
+	if deadline.IsZero() {
+		w.clearLocked()
+		return nil
+	}
+
+	now := time.Now()
+	switch {
+	case deadline.Before(time.Unix(0, 0)):
+		w.clearLocked()
+		return fmt.Errorf("%w: %v", ErrDeadlineBeforeEpoch, deadline)
+	case deadline.After(now.Add(maxDeadlineHorizon)):
+		w.clearLocked()
+		return fmt.Errorf("%w: %v", ErrDeadlineTooFarFuture, deadline)
+	case deadline.Before(now.Add(-maxPastHorizon)):
+		w.clearLocked()
+		return fmt.Errorf("%w: %v (now=%v)", ErrDeadlineInPast, deadline, now)
+	}
+
+	if deadline.Equal(w.current) {
+		w.mu.Unlock()
+		return nil
+	}
+
+	w.stopTimerLocked()
+	w.current = deadline
+	// Reset every per-deadline guard so a refreshed deadline arms a fresh
+	// warning cycle: both edge triggers and the user Dismiss decision
+	// (the user agreed to the old deadline expiring; a new deadline
+	// restarts the contract).
+	w.firedAt = time.Time{}
+	w.finalFiredAt = time.Time{}
+	w.dismissedAt = time.Time{}
+
+	if deadline.After(now) {
+		w.armTimerLocked(deadline)
+	}
+	recorder := w.recorder
+	w.mu.Unlock()
+	if recorder != nil {
+		recorder.SetSessionExpiresAt(deadline)
+	}
+	log.Infof("auth session deadline set to: %s (in %s)", deadline.Format(time.RFC3339), time.Until(deadline).Round(time.Second))
+	return nil
+}
+
+// Deadline returns the most recently observed deadline. Zero when no
+// deadline is currently tracked.
+func (w *Watcher) Deadline() time.Time {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	return w.current
+}
+
+// Dismiss records the user's "Dismiss" action against the current deadline
+// and suppresses the upcoming final-warning callback for that deadline.
+// Idempotent: repeated calls are no-ops. A subsequent Update with a fresh
+// deadline resets the dismissal so the final-warning cycle re-arms.
+//
+// No-op when the watcher holds no deadline or has been closed.
+func (w *Watcher) Dismiss() {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	if w.closed || w.current.IsZero() {
+		return
+	}
+	if w.dismissedAt.Equal(w.current) {
+		return
+	}
+	w.dismissedAt = w.current
+	// Cancel the armed final-warning timer eagerly. fireFinal would also
+	// gate on dismissedAt, but stopping the timer avoids a wakeup with
+	// nothing to do and makes the intent visible.
+	if w.finalTimer != nil {
+		w.finalTimer.Stop()
+		w.finalTimer = nil
+	}
+	log.Infof("auth session final-warning dismissed for deadline %s", w.current.Format(time.RFC3339))
+}
+
+// Close stops any pending timer. Update calls after Close are ignored.
+// The recorder keeps its deadline: the watcher is engine-scoped and closes
+// on every engine restart (network change, sleep/wake, stream errors)
+// while the SSO deadline stays valid across those, so clearing here would
+// blank the UI's "expires in" row on every transient reconnect. The
+// client run loop clears the server-scoped recorder when it exits for
+// real (Down, profile switch, permanent login failure).
+func (w *Watcher) Close() {
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	if w.closed {
+		return
+	}
+	w.closed = true
+	w.stopTimerLocked()
+	w.current = time.Time{}
+	w.firedAt = time.Time{}
+	w.finalFiredAt = time.Time{}
+	w.dismissedAt = time.Time{}
+}
+
+// clearLocked drops the tracked deadline and notifies the recorder so
+// downstream consumers (SubscribeStatus stream, UI) drop their anchor.
+// The caller must hold w.mu; this helper releases it before invoking
+// the recorder.
+func (w *Watcher) clearLocked() {
+	if w.current.IsZero() {
+		w.mu.Unlock()
+		return
+	}
+	w.stopTimerLocked()
+	w.current = time.Time{}
+	w.firedAt = time.Time{}
+	w.finalFiredAt = time.Time{}
+	w.dismissedAt = time.Time{}
+	recorder := w.recorder
+	w.mu.Unlock()
+	if recorder != nil {
+		recorder.SetSessionExpiresAt(time.Time{})
+	}
+	log.Infof("auth session deadline cleared")
+}
+
+func (w *Watcher) stopTimerLocked() {
+	if w.timer != nil {
+		w.timer.Stop()
+		w.timer = nil
+	}
+	if w.finalTimer != nil {
+		w.finalTimer.Stop()
+		w.finalTimer = nil
+	}
+}
+
+func (w *Watcher) armTimerLocked(deadline time.Time) {
+	w.timer = armOneShotLocked(deadline.Add(-w.lead), func() { w.fire(deadline) })
+	// finalLead <= 0 disables the final-warning timer entirely. Used by
+	// tests that predate the final-warning fallback so a millisecond-scale
+	// deadline does not flush both timers at once.
+	if w.finalLead > 0 {
+		w.finalTimer = armOneShotLocked(deadline.Add(-w.finalLead), func() { w.fireFinal(deadline) })
+	}
+}
+
+func (w *Watcher) fire(armedFor time.Time) {
+	w.mu.Lock()
+	if w.closed || !w.current.Equal(armedFor) {
+		// Deadline moved while we were waiting (e.g. a successful extend).
+		// The reschedule path armed a fresh timer; this one is stale.
+		w.mu.Unlock()
+		return
+	}
+	if !w.firedAt.IsZero() && w.firedAt.Equal(armedFor) {
+		w.mu.Unlock()
+		return
+	}
+	w.firedAt = armedFor
+	recorder := w.recorder
+	w.mu.Unlock()
+	if recorder == nil {
+		return
+	}
+	log.Infof("auth session expiry soon warning fired")
+	publishWarning(recorder, armedFor, false)
+}
+
+// fireFinal mirrors fire for the T-FinalWarningLead timer with an extra
+// dismiss-gate: if the user dismissed the T-WarningLead notification for
+// this deadline, the final warning is suppressed entirely.
+func (w *Watcher) fireFinal(armedFor time.Time) {
+	w.mu.Lock()
+	if w.closed || !w.current.Equal(armedFor) {
+		w.mu.Unlock()
+		return
+	}
+	if !w.finalFiredAt.IsZero() && w.finalFiredAt.Equal(armedFor) {
+		w.mu.Unlock()
+		return
+	}
+	if w.dismissedAt.Equal(armedFor) {
+		w.mu.Unlock()
+		log.Infof("auth session final-warning skipped (dismissed by user)")
+		return
+	}
+	w.finalFiredAt = armedFor
+	recorder := w.recorder
+	w.mu.Unlock()
+	if recorder == nil {
+		return
+	}
+	log.Infof("auth session final-warning fired")
+	publishWarning(recorder, armedFor, true)
+}
+
+// armOneShotLocked schedules cb at fireAt. When fireAt is already in the
+// past it dispatches on the next scheduler tick so a state-change recorder
+// notification (invoked after w.mu is released) lands first. Caller must
+// hold w.mu.
+func armOneShotLocked(fireAt time.Time, cb func()) *time.Timer {
+	delay := time.Until(fireAt)
+	if delay <= 0 {
+		return time.AfterFunc(0, cb)
+	}
+	return time.AfterFunc(delay, cb)
+}
+
+// publishWarning composes the SystemEvent for a watcher-fired warning and
+// pushes it through the recorder. Severity is CRITICAL on both — bypassing
+// the user's Notifications toggle is deliberate: missing the warning
+// window forces the post-mortem SessionExpired flow (tunnel torn down,
+// lock icon, manual re-login), which is the UX we are trying to avoid.
+func publishWarning(recorder StatusRecorder, deadline time.Time, final bool) {
+	lead := WarningLead
+	message := "session expiry warning"
+	meta := map[string]string{
+		MetaSessionWarning:   "true",
+		MetaSessionExpiresAt: FormatExpiresAt(deadline),
+	}
+	if final {
+		lead = FinalWarningLead
+		message = "session expiry final warning"
+		meta[MetaSessionFinal] = "true"
+	}
+	meta[MetaSessionLeadMinutes] = FormatLeadMinutes(lead)
+
+	recorder.PublishEvent(
+		cProto.SystemEvent_CRITICAL,
+		cProto.SystemEvent_AUTHENTICATION,
+		message,
+		"",
+		meta,
+	)
+}

client/internal/auth/sessionwatch/watcher_test.go

@@ -0,0 +1,529 @@
+package sessionwatch
+
+import (
+	"errors"
+	"sync"
+	"testing"
+	"time"
+
+	cProto "github.com/netbirdio/netbird/client/proto"
+)
+
+// fakeRecorder satisfies StatusRecorder and records every call so tests
+// can observe what the watcher emits. SetSessionExpiresAt and PublishEvent
+// land in the same ordered events slice (with the Kind distinguishing
+// them) so tests that care about ordering still work. lastDeadline holds
+// the most recent value passed to SetSessionExpiresAt so tests can assert
+// the recorder ended up cleared/set as expected.
+type fakeRecorder struct {
+	mu           sync.Mutex
+	events       []event
+	lastDeadline time.Time
+}
+
+type eventKind int
+
+const (
+	stateChange eventKind = iota
+	publish
+)
+
+type event struct {
+	kind eventKind
+	// Set only for publish events.
+	severity cProto.SystemEvent_Severity
+	category cProto.SystemEvent_Category
+	message  string
+	meta     map[string]string
+}
+
+// SetSessionExpiresAt mirrors peer.Status: a same-value write is a no-op,
+// a real change records the new value and fans out a state-change (the
+// production recorder calls notifyStateChange internally). The baseline
+// is the zero time, so an initial clear before any deadline is set emits
+// nothing — matching the real recorder.
+func (r *fakeRecorder) SetSessionExpiresAt(deadline time.Time) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	if r.lastDeadline.Equal(deadline) {
+		return
+	}
+	r.lastDeadline = deadline
+	r.events = append(r.events, event{kind: stateChange})
+}
+
+func (r *fakeRecorder) deadline() time.Time {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	return r.lastDeadline
+}
+
+func (r *fakeRecorder) PublishEvent(
+	severity cProto.SystemEvent_Severity,
+	category cProto.SystemEvent_Category,
+	message string,
+	_ string,
+	metadata map[string]string,
+) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.events = append(r.events, event{
+		kind:     publish,
+		severity: severity,
+		category: category,
+		message:  message,
+		meta:     metadata,
+	})
+}
+
+func (r *fakeRecorder) snapshot() []event {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	out := make([]event, len(r.events))
+	copy(out, r.events)
+	return out
+}
+
+func (e event) isFinalWarning() bool {
+	return e.kind == publish && e.meta[MetaSessionFinal] == "true"
+}
+
+func (e event) isWarning() bool {
+	return e.kind == publish && e.meta[MetaSessionWarning] == "true" && e.meta[MetaSessionFinal] != "true"
+}
+
+func countWhere(events []event, pred func(event) bool) int {
+	n := 0
+	for _, e := range events {
+		if pred(e) {
+			n++
+		}
+	}
+	return n
+}
+
+func waitForEvents(t *testing.T, r *fakeRecorder, want int) []event {
+	t.Helper()
+	deadline := time.Now().Add(500 * time.Millisecond)
+	for time.Now().Before(deadline) {
+		if got := r.snapshot(); len(got) >= want {
+			return got
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+	got := r.snapshot()
+	t.Fatalf("timed out waiting for %d events, got %d: %+v", want, len(got), got)
+	return nil
+}
+
+// newWatcher builds a watcher with the final timer disabled (finalLead=0),
+// matching the lead-only behaviour the pre-final-warning tests assume.
+func newWatcher(lead time.Duration, r *fakeRecorder) *Watcher {
+	return NewWithLeads(lead, 0, r)
+}
+
+func TestUpdateZeroBeforeAnythingIsNoop(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	defer w.Close()
+
+	_ = w.Update(time.Time{})
+
+	if got := r.snapshot(); len(got) != 0 {
+		t.Fatalf("expected no events on initial zero, got %+v", got)
+	}
+}
+
+func TestUpdateNonZeroFiresStateChange(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	defer w.Close()
+
+	d := time.Now().Add(time.Hour)
+	_ = w.Update(d)
+
+	events := waitForEvents(t, r, 1)
+	if events[0].kind != stateChange {
+		t.Fatalf("expected stateChange, got %+v", events[0])
+	}
+	if !w.Deadline().Equal(d) {
+		t.Fatalf("deadline mismatch: %v vs %v", w.Deadline(), d)
+	}
+}
+
+func TestSameDeadlineIsNoop(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	defer w.Close()
+
+	d := time.Now().Add(time.Hour)
+	_ = w.Update(d)
+	_ = w.Update(d)
+	_ = w.Update(d)
+
+	events := waitForEvents(t, r, 1)
+	if len(events) != 1 {
+		t.Fatalf("expected exactly 1 event for repeated same deadline, got %d: %+v", len(events), events)
+	}
+}
+
+func TestWarningFiresOnceWithinLeadWindow(t *testing.T) {
+	r := &fakeRecorder{}
+	lead := 50 * time.Millisecond
+	w := newWatcher(lead, r)
+	defer w.Close()
+
+	// Deadline 80ms out — warning should fire after ~30ms.
+	d := time.Now().Add(80 * time.Millisecond)
+	_ = w.Update(d)
+
+	events := waitForEvents(t, r, 2)
+	if events[0].kind != stateChange {
+		t.Fatalf("event[0] should be stateChange, got %+v", events[0])
+	}
+	if !events[1].isWarning() {
+		t.Fatalf("event[1] should be a warning publish, got %+v", events[1])
+	}
+}
+
+func TestWarningFiresImmediatelyWhenAlreadyInsideWindow(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(time.Hour, r) // lead > delta => fire immediately
+	defer w.Close()
+
+	d := time.Now().Add(10 * time.Millisecond)
+	_ = w.Update(d)
+
+	events := waitForEvents(t, r, 2)
+	if !events[1].isWarning() {
+		t.Fatalf("expected immediate warning publish, got %+v", events[1])
+	}
+}
+
+func TestNewDeadlineCancelsPriorTimer(t *testing.T) {
+	r := &fakeRecorder{}
+	lead := 50 * time.Millisecond
+	w := newWatcher(lead, r)
+	defer w.Close()
+
+	first := time.Now().Add(80 * time.Millisecond) // would fire warning ~30ms in
+	_ = w.Update(first)
+
+	// Replace with a far-future deadline before the warning fires.
+	time.Sleep(5 * time.Millisecond)
+	second := time.Now().Add(time.Hour)
+	_ = w.Update(second)
+
+	// Wait past when first's warning would have fired.
+	time.Sleep(80 * time.Millisecond)
+
+	if n := countWhere(r.snapshot(), event.isWarning); n != 0 {
+		t.Fatalf("warning fired for cancelled deadline: %+v", r.snapshot())
+	}
+}
+
+func TestRefreshAfterFireArmsNewWarning(t *testing.T) {
+	r := &fakeRecorder{}
+	lead := 150 * time.Millisecond
+	w := newWatcher(lead, r)
+	defer w.Close()
+
+	// Warning fires ~20ms in; the deadline itself stays 150ms away so the
+	// replacement below lands well before it.
+	first := time.Now().Add(170 * time.Millisecond)
+	_ = w.Update(first)
+
+	// Wait for stateChange + warning of the first cycle.
+	waitForEvents(t, r, 2)
+
+	// Simulate a successful extend: brand new deadline.
+	second := time.Now().Add(60 * time.Millisecond)
+	_ = w.Update(second)
+
+	// 4 events total: stateChange, warning (first), stateChange, warning (second).
+	events := waitForEvents(t, r, 4)
+	if events[2].kind != stateChange {
+		t.Fatalf("event[2] should be stateChange for the new deadline, got %+v", events[2])
+	}
+	if !events[3].isWarning() {
+		t.Fatalf("event[3] should be a warning publish for the new deadline, got %+v", events[3])
+	}
+}
+
+func TestUpdateZeroAfterNonZeroClearsState(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(time.Hour, r)
+	defer w.Close()
+
+	d := time.Now().Add(2 * time.Hour)
+	_ = w.Update(d)
+	waitForEvents(t, r, 1)
+
+	_ = w.Update(time.Time{})
+
+	events := waitForEvents(t, r, 2)
+	if events[1].kind != stateChange {
+		t.Fatalf("expected stateChange on clear, got %+v", events[1])
+	}
+	if !w.Deadline().IsZero() {
+		t.Fatalf("Deadline should be zero after clear")
+	}
+}
+
+func TestUpdateRejectsBeforeEpoch(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	defer w.Close()
+
+	good := time.Now().Add(time.Hour)
+	if err := w.Update(good); err != nil {
+		t.Fatalf("seed Update: %v", err)
+	}
+
+	err := w.Update(time.Unix(-100, 0))
+	if !errors.Is(err, ErrDeadlineBeforeEpoch) {
+		t.Fatalf("want ErrDeadlineBeforeEpoch, got %v", err)
+	}
+	if !w.Deadline().IsZero() {
+		t.Fatalf("rejected pre-epoch update must clear deadline; got %v", w.Deadline())
+	}
+}
+
+func TestUpdateRejectsTooFarFuture(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	defer w.Close()
+
+	good := time.Now().Add(time.Hour)
+	if err := w.Update(good); err != nil {
+		t.Fatalf("seed Update: %v", err)
+	}
+
+	err := w.Update(time.Now().Add(50 * 365 * 24 * time.Hour))
+	if !errors.Is(err, ErrDeadlineTooFarFuture) {
+		t.Fatalf("want ErrDeadlineTooFarFuture, got %v", err)
+	}
+	if !w.Deadline().IsZero() {
+		t.Fatalf("rejected far-future update must clear deadline; got %v", w.Deadline())
+	}
+}
+
+func TestUpdateRecentPastRecordedAsExpired(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	defer w.Close()
+
+	d := time.Now().Add(-1 * time.Hour)
+	if err := w.Update(d); err != nil {
+		t.Fatalf("recent-past Update should succeed, got %v", err)
+	}
+	if !w.Deadline().Equal(d) {
+		t.Fatalf("expected deadline to be recorded, got %v want %v", w.Deadline(), d)
+	}
+	if got := r.deadline(); !got.Equal(d) {
+		t.Fatalf("recorder deadline = %v, want %v", got, d)
+	}
+
+	time.Sleep(80 * time.Millisecond)
+	if n := countWhere(r.snapshot(), func(e event) bool { return e.kind == publish }); n != 0 {
+		t.Fatalf("no warning events may fire for an already-past deadline, got %+v", r.snapshot())
+	}
+}
+
+func TestUpdateAncientPastRejected(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	defer w.Close()
+
+	good := time.Now().Add(time.Hour)
+	if err := w.Update(good); err != nil {
+		t.Fatalf("seed Update: %v", err)
+	}
+	// Drain the stateChange from the seed.
+	waitForEvents(t, r, 1)
+
+	err := w.Update(time.Now().Add(-31 * 24 * time.Hour))
+	if !errors.Is(err, ErrDeadlineInPast) {
+		t.Fatalf("want ErrDeadlineInPast, got %v", err)
+	}
+	if !w.Deadline().IsZero() {
+		t.Fatalf("rejected ancient-past update must clear the deadline, got %v", w.Deadline())
+	}
+	events := waitForEvents(t, r, 2)
+	if events[1].kind != stateChange {
+		t.Fatalf("expected stateChange on clear, got %+v", events[1])
+	}
+}
+
+func TestCloseSilencesUpdates(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(50*time.Millisecond, r)
+	w.Close()
+
+	if err := w.Update(time.Now().Add(time.Hour)); err != nil {
+		t.Fatalf("Update after Close: want nil, got %v", err)
+	}
+	if got := r.snapshot(); len(got) != 0 {
+		t.Fatalf("expected no events after Close, got %+v", got)
+	}
+}
+
+// TestCloseKeepsRecorderDeadline pins the reconnect-flap fix: the watcher
+// closes on every engine restart (network change, sleep/wake) while the
+// SSO deadline stays valid across those, so Close must leave the
+// server-scoped recorder's value in place. The client run loop clears the
+// recorder when it exits for real.
+func TestCloseKeepsRecorderDeadline(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(time.Hour, r)
+
+	d := time.Now().Add(2 * time.Hour)
+	if err := w.Update(d); err != nil {
+		t.Fatalf("seed Update: %v", err)
+	}
+	if got := r.deadline(); !got.Equal(d) {
+		t.Fatalf("recorder deadline after Update = %v, want %v", got, d)
+	}
+
+	w.Close()
+
+	if got := r.deadline(); !got.Equal(d) {
+		t.Fatalf("recorder deadline after Close = %v, want %v", got, d)
+	}
+}
+
+// TestCloseWithoutDeadlineLeavesRecorderUntouched guards the symmetric
+// case: closing a watcher that never held a deadline must not emit a
+// redundant clear (the recorder may legitimately hold a value written by
+// some other path; the watcher only owns what it set).
+func TestCloseWithoutDeadlineLeavesRecorderUntouched(t *testing.T) {
+	r := &fakeRecorder{}
+	w := newWatcher(time.Hour, r)
+
+	w.Close()
+
+	if got := r.snapshot(); len(got) != 0 {
+		t.Fatalf("expected no events from Close on an empty watcher, got %+v", got)
+	}
+}
+
+func TestFinalWarningFiresAfterRegularWarning(t *testing.T) {
+	r := &fakeRecorder{}
+	// Warning fires at deadline-80ms, final at deadline-30ms.
+	w := NewWithLeads(80*time.Millisecond, 30*time.Millisecond, r)
+	defer w.Close()
+
+	d := time.Now().Add(100 * time.Millisecond)
+	_ = w.Update(d)
+
+	// Expect stateChange + warning + final-warning.
+	events := waitForEvents(t, r, 3)
+
+	if countWhere(events, func(e event) bool { return e.kind == stateChange }) != 1 {
+		t.Fatalf("expected exactly 1 stateChange, got %+v", events)
+	}
+	if countWhere(events, event.isWarning) != 1 {
+		t.Fatalf("expected exactly 1 warning publish, got %+v", events)
+	}
+	if countWhere(events, event.isFinalWarning) != 1 {
+		t.Fatalf("expected exactly 1 final-warning publish, got %+v", events)
+	}
+
+	// Warning must precede final (same deadline, longer lead fires first).
+	var wIdx, fIdx int
+	for i, e := range events {
+		switch {
+		case e.isWarning():
+			wIdx = i
+		case e.isFinalWarning():
+			fIdx = i
+		}
+	}
+	if wIdx > fIdx {
+		t.Fatalf("warning must publish before final-warning, got order %+v", events)
+	}
+}
+
+func TestDismissSuppressesFinalWarning(t *testing.T) {
+	r := &fakeRecorder{}
+	w := NewWithLeads(80*time.Millisecond, 30*time.Millisecond, r)
+	defer w.Close()
+
+	d := time.Now().Add(100 * time.Millisecond)
+	_ = w.Update(d)
+
+	// Wait for the warning publish so we know we're inside the warning
+	// window, then dismiss before the final timer would fire.
+	deadline := time.Now().Add(500 * time.Millisecond)
+	for time.Now().Before(deadline) {
+		if countWhere(r.snapshot(), event.isWarning) >= 1 {
+			break
+		}
+		time.Sleep(2 * time.Millisecond)
+	}
+	if countWhere(r.snapshot(), event.isWarning) < 1 {
+		t.Fatalf("warning did not publish in time, events=%+v", r.snapshot())
+	}
+
+	w.Dismiss()
+
+	// Now wait past when the final would have fired.
+	time.Sleep(120 * time.Millisecond)
+
+	if n := countWhere(r.snapshot(), event.isFinalWarning); n != 0 {
+		t.Fatalf("final-warning published after Dismiss(), events=%+v", r.snapshot())
+	}
+}
+
+func TestDismissResetByNewDeadline(t *testing.T) {
+	r := &fakeRecorder{}
+	w := NewWithLeads(80*time.Millisecond, 30*time.Millisecond, r)
+	defer w.Close()
+
+	first := time.Now().Add(100 * time.Millisecond)
+	_ = w.Update(first)
+
+	// Dismiss against the first deadline.
+	w.Dismiss()
+
+	// Replace with a fresh deadline before the first's timers complete.
+	time.Sleep(10 * time.Millisecond)
+	second := time.Now().Add(100 * time.Millisecond)
+	_ = w.Update(second)
+
+	// The second cycle must publish a final-warning (the dismiss state
+	// did not carry over).
+	deadline := time.Now().Add(500 * time.Millisecond)
+	for time.Now().Before(deadline) {
+		if countWhere(r.snapshot(), event.isFinalWarning) >= 1 {
+			break
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+	if countWhere(r.snapshot(), event.isFinalWarning) < 1 {
+		t.Fatalf("final-warning did not publish on fresh deadline after Dismiss reset, events=%+v", r.snapshot())
+	}
+}
+
+func TestDismissBeforeUpdateIsNoop(t *testing.T) {
+	r := &fakeRecorder{}
+	w := NewWithLeads(80*time.Millisecond, 30*time.Millisecond, r)
+	defer w.Close()
+
+	// No deadline tracked yet; Dismiss must be a no-op (no panic, no state).
+	w.Dismiss()
+
+	d := time.Now().Add(100 * time.Millisecond)
+	_ = w.Update(d)
+
+	// Final warning should still publish — Dismiss only acts on the current
+	// deadline, and there was none at the time of the call.
+	deadline := time.Now().Add(500 * time.Millisecond)
+	for time.Now().Before(deadline) {
+		if countWhere(r.snapshot(), event.isFinalWarning) >= 1 {
+			return
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+	t.Fatalf("final-warning did not publish after no-op pre-Update Dismiss, events=%+v", r.snapshot())
+}

client/internal/auth/util.go

@@ -20,14 +20,26 @@ func randomBytesInHex(count int) (string, error) {
 	return hex.EncodeToString(buf), nil
 }
 
-// isValidAccessToken is a simple validation of the access token
-func isValidAccessToken(token string, audience string) error {
+// validateTokenAudience checks that the token is a well-formed JWT whose
+// audience claim matches the expected audience.
+//
+// It does NOT verify the token's cryptographic signature and therefore must not
+// be treated as an authenticity check. The token is obtained by the client
+// directly from the IdP token endpoint over TLS, and its signature is verified
+// server-side by the management server against the IdP's JWKS
+// (see shared/auth/jwt/validator.go). This function is only a client-side
+// sanity check that the returned token targets the expected audience.
+func validateTokenAudience(token string, audience string) error {
 	if token == "" {
 		return fmt.Errorf("token received is empty")
 	}
 
-	encodedClaims := strings.Split(token, ".")[1]
-	claimsString, err := base64.RawURLEncoding.DecodeString(encodedClaims)
+	parts := strings.Split(token, ".")
+	if len(parts) != 3 {
+		return fmt.Errorf("token is not a well-formed JWT")
+	}
+
+	claimsString, err := base64.RawURLEncoding.DecodeString(parts[1])
 	if err != nil {
 		return err
 	}

client/internal/auth/util_test.go

@@ -0,0 +1,108 @@
+package auth
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"testing"
+)
+
+// makeJWT builds an unsigned JWT-shaped string (header.payload.signature) with
+// the given claims payload. The signature part is arbitrary because
+// validateTokenAudience intentionally does not verify it.
+func makeJWT(t *testing.T, claims map[string]interface{}) string {
+	t.Helper()
+	header := base64.RawURLEncoding.EncodeToString([]byte(`{"alg":"RS256","typ":"JWT"}`))
+	payloadBytes, err := json.Marshal(claims)
+	if err != nil {
+		t.Fatalf("marshal claims: %v", err)
+	}
+	payload := base64.RawURLEncoding.EncodeToString(payloadBytes)
+	return header + "." + payload + ".unverified-signature"
+}
+
+func TestValidateTokenAudience(t *testing.T) {
+	tests := []struct {
+		name     string
+		token    string
+		audience string
+		wantErr  bool
+	}{
+		{
+			name:     "empty token",
+			token:    "",
+			audience: "netbird",
+			wantErr:  true,
+		},
+		{
+			name:     "not a JWT - no dots",
+			token:    "notajwt",
+			audience: "netbird",
+			wantErr:  true,
+		},
+		{
+			name:     "not a JWT - two parts only",
+			token:    "header.payload",
+			audience: "netbird",
+			wantErr:  true,
+		},
+		{
+			name:     "matching string audience",
+			token:    makeJWT(t, map[string]interface{}{"aud": "netbird"}),
+			audience: "netbird",
+			wantErr:  false,
+		},
+		{
+			name:     "mismatching string audience",
+			token:    makeJWT(t, map[string]interface{}{"aud": "other"}),
+			audience: "netbird",
+			wantErr:  true,
+		},
+		{
+			name:     "matching audience in array",
+			token:    makeJWT(t, map[string]interface{}{"aud": []interface{}{"other", "netbird"}}),
+			audience: "netbird",
+			wantErr:  false,
+		},
+		{
+			name:     "mismatching audience array",
+			token:    makeJWT(t, map[string]interface{}{"aud": []interface{}{"a", "b"}}),
+			audience: "netbird",
+			wantErr:  true,
+		},
+		{
+			name:     "missing audience claim",
+			token:    makeJWT(t, map[string]interface{}{"sub": "user"}),
+			audience: "netbird",
+			wantErr:  true,
+		},
+		{
+			name:     "invalid base64 payload",
+			token:    "header.!!!not-base64!!!.sig",
+			audience: "netbird",
+			wantErr:  true,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			err := validateTokenAudience(tc.token, tc.audience)
+			if tc.wantErr && err == nil {
+				t.Fatalf("expected error, got nil")
+			}
+			if !tc.wantErr && err != nil {
+				t.Fatalf("expected no error, got %v", err)
+			}
+		})
+	}
+}
+
+// TestValidateTokenAudienceNoPanic guards the regression where a non-empty
+// token without the JWT dot structure caused an index-out-of-range panic.
+func TestValidateTokenAudienceNoPanic(t *testing.T) {
+	inputs := []string{"a", ".", "a.", "aaaa", "no-dots-here"}
+	for _, in := range inputs {
+		if err := validateTokenAudience(in, "netbird"); err == nil {
+			t.Fatalf("expected error for malformed token %q, got nil", in)
+		}
+	}
+}

client/internal/conn_mgr.go

@@ -16,6 +16,16 @@ import (
 	"github.com/netbirdio/netbird/route"
 )
 
+// lazyForce is the resolved local decision for lazy connections, layered above the
+// management feature flag. lazyForceNone defers to management.
+type lazyForce int
+
+const (
+	lazyForceNone lazyForce = iota
+	lazyForceOn
+	lazyForceOff
+)
+
 // ConnMgr coordinates both lazy connections (established on-demand) and permanent peer connections.
 //
 // The connection manager is responsible for:
@@ -24,47 +34,69 @@ import (
 // - Handling connection establishment based on peer signaling
 //
 // The implementation is not thread-safe; it is protected by engine.syncMsgMux.
+// The only exception is ActivatePeer, which is safe for concurrent use so the
+// DNS warm-up path can call it without contending on the engine mutex.
 type ConnMgr struct {
 	peerStore        *peerstore.Store
 	statusRecorder   *peer.Status
 	iface            lazyconn.WGIface
-	enabledLocally   bool
+	force            lazyForce
 	rosenpassEnabled bool
 
 	lazyConnMgr *manager.Manager
+	// lazyConnMgrMu guards the lazyConnMgr pointer for readers outside the
+	// engine loop (ActivatePeer). Writers hold it in addition to
+	// engine.syncMsgMux; all other reads stay under engine.syncMsgMux only.
+	lazyConnMgrMu sync.RWMutex
+
+	// reconcileRoutedIPs re-applies a peer's routed allowed IPs after its lazy wake endpoint is
+	// (re)armed (Mode A at arm time). Injected by the engine; nil disables the reconcile.
+	reconcileRoutedIPs func(peerKey string) error
 
 	wg            sync.WaitGroup
 	lazyCtx       context.Context
 	lazyCtxCancel context.CancelFunc
 }
 
+// SetRoutedIPsReconciler injects the callback used to re-apply a peer's routed allowed IPs when
+// its lazy wake endpoint is (re)armed. Must be called before the lazy manager starts.
+func (e *ConnMgr) SetRoutedIPsReconciler(fn func(peerKey string) error) {
+	e.reconcileRoutedIPs = fn
+}
+
 func NewConnMgr(engineConfig *EngineConfig, statusRecorder *peer.Status, peerStore *peerstore.Store, iface lazyconn.WGIface) *ConnMgr {
 	e := &ConnMgr{
 		peerStore:        peerStore,
 		statusRecorder:   statusRecorder,
 		iface:            iface,
+		force:            resolveLazyForce(engineConfig.LazyConnection),
 		rosenpassEnabled: engineConfig.RosenpassEnabled,
 	}
-	if engineConfig.LazyConnectionEnabled || lazyconn.IsLazyConnEnabledByEnv() {
-		e.enabledLocally = true
-	}
 	return e
 }
 
-// Start initializes the connection manager and starts the lazy connection manager if enabled by env var or cmd line option.
+// Start initializes the connection manager. It starts the lazy connection manager when a
+// local override forces it on; with no local override it waits for the management feature flag.
 func (e *ConnMgr) Start(ctx context.Context) {
 	if e.lazyConnMgr != nil {
 		log.Errorf("lazy connection manager is already started")
 		return
 	}
 
-	if !e.enabledLocally {
-		log.Infof("lazy connection manager is disabled")
+	switch e.force {
+	case lazyForceOff:
+		log.Infof("lazy connection manager is disabled by local override (%s or MDM policy)", lazyconn.EnvLazyConn)
+		e.statusRecorder.UpdateLazyConnection(false)
+		return
+	case lazyForceNone:
+		log.Infof("lazy connection manager is managed by the management feature flag")
+		e.statusRecorder.UpdateLazyConnection(false)
 		return
 	}
 
 	if e.rosenpassEnabled {
 		log.Warnf("rosenpass connection manager is enabled, lazy connection manager will not be started")
+		e.statusRecorder.UpdateLazyConnection(false)
 		return
 	}
 
@@ -76,8 +108,8 @@ func (e *ConnMgr) Start(ctx context.Context) {
 // If enabled, it initializes the lazy connection manager and start it. Do not need to call Start() again.
 // If disabled, then it closes the lazy connection manager and open the connections to all peers.
 func (e *ConnMgr) UpdatedRemoteFeatureFlag(ctx context.Context, enabled bool) error {
-	// do not disable lazy connection manager if it was enabled by env var
-	if e.enabledLocally {
+	// a local override (NB_LAZY_CONN or local config) takes precedence over management
+	if e.force != lazyForceNone {
 		return nil
 	}
 
@@ -89,15 +121,17 @@ func (e *ConnMgr) UpdatedRemoteFeatureFlag(ctx context.Context, enabled bool) er
 
 		if e.rosenpassEnabled {
 			log.Infof("rosenpass connection manager is enabled, lazy connection manager will not be started")
+			e.statusRecorder.UpdateLazyConnection(false)
 			return nil
 		}
 
-		log.Warnf("lazy connection manager is enabled by management feature flag")
+		log.Infof("lazy connection manager is enabled by the management feature flag")
 		e.initLazyManager(ctx)
 		e.statusRecorder.UpdateLazyConnection(true)
 		return e.addPeersToLazyConnManager()
 	} else {
 		if e.lazyConnMgr == nil {
+			e.statusRecorder.UpdateLazyConnection(false)
 			return nil
 		}
 		log.Infof("lazy connection manager is disabled by management feature flag")
@@ -220,12 +254,20 @@ func (e *ConnMgr) RemovePeerConn(peerKey string) {
 	conn.Log.Infof("removed peer from lazy conn manager")
 }
 
+// ActivatePeer wakes an idle lazy connection. Unlike the rest of ConnMgr it is
+// safe for concurrent use: the lazy manager pointer is read under lazyConnMgrMu
+// and the manager itself is internally synchronized, so callers outside the
+// engine loop (DNS warm-up) do not need engine.syncMsgMux.
 func (e *ConnMgr) ActivatePeer(ctx context.Context, conn *peer.Conn) {
-	if !e.isStartedWithLazyMgr() {
+	e.lazyConnMgrMu.RLock()
+	lazyConnMgr := e.lazyConnMgr
+	started := lazyConnMgr != nil && e.lazyCtxCancel != nil
+	e.lazyConnMgrMu.RUnlock()
+	if !started {
 		return
 	}
 
-	if found := e.lazyConnMgr.ActivatePeer(conn.GetKey()); found {
+	if found := lazyConnMgr.ActivatePeer(conn.GetKey()); found {
 		if err := conn.Open(ctx); err != nil {
 			conn.Log.Errorf("failed to open connection: %v", err)
 		}
@@ -250,16 +292,22 @@ func (e *ConnMgr) Close() {
 
 	e.lazyCtxCancel()
 	e.wg.Wait()
+
+	e.lazyConnMgrMu.Lock()
 	e.lazyConnMgr = nil
+	e.lazyConnMgrMu.Unlock()
 }
 
 func (e *ConnMgr) initLazyManager(engineCtx context.Context) {
 	cfg := manager.Config{
 		InactivityThreshold: inactivityThresholdEnv(),
+		ReconcileAllowedIPs: e.reconcileRoutedIPs,
 	}
-	e.lazyConnMgr = manager.NewManager(cfg, engineCtx, e.peerStore, e.iface)
 
+	e.lazyConnMgrMu.Lock()
+	e.lazyConnMgr = manager.NewManager(cfg, engineCtx, e.peerStore, e.iface)
 	e.lazyCtx, e.lazyCtxCancel = context.WithCancel(engineCtx)
+	e.lazyConnMgrMu.Unlock()
 
 	e.wg.Add(1)
 	go func() {
@@ -298,7 +346,10 @@ func (e *ConnMgr) closeManager(ctx context.Context) {
 
 	e.lazyCtxCancel()
 	e.wg.Wait()
+
+	e.lazyConnMgrMu.Lock()
 	e.lazyConnMgr = nil
+	e.lazyConnMgrMu.Unlock()
 
 	for _, peerID := range e.peerStore.PeersPubKey() {
 		e.peerStore.PeerConnOpen(ctx, peerID)
@@ -309,17 +360,45 @@ func (e *ConnMgr) isStartedWithLazyMgr() bool {
 	return e.lazyConnMgr != nil && e.lazyCtxCancel != nil
 }
 
+// resolveLazyForce determines the local override. NB_LAZY_CONN takes precedence; when it
+// is unset the MDM policy override (mdmState) applies. Either wins in both directions over
+// the management feature flag; StateUnset for both defers to management.
+func resolveLazyForce(mdmState lazyconn.State) lazyForce {
+	state := lazyconn.EnvState()
+	if state == lazyconn.StateUnset {
+		state = mdmState
+	}
+
+	switch state {
+	case lazyconn.StateOn:
+		return lazyForceOn
+	case lazyconn.StateOff:
+		return lazyForceOff
+	default:
+		return lazyForceNone
+	}
+}
+
 func inactivityThresholdEnv() *time.Duration {
 	envValue := os.Getenv(lazyconn.EnvInactivityThreshold)
 	if envValue == "" {
 		return nil
 	}
 
-	parsedMinutes, err := strconv.Atoi(envValue)
-	if err != nil || parsedMinutes <= 0 {
-		return nil
+	// Documented format: a Go duration such as "30m" or "1h".
+	if d, err := time.ParseDuration(envValue); err == nil {
+		if d <= 0 {
+			return nil
+		}
+		return &d
 	}
 
-	d := time.Duration(parsedMinutes) * time.Minute
-	return &d
+	// Backwards compatibility: a bare integer used to be interpreted as minutes.
+	if parsedMinutes, err := strconv.Atoi(envValue); err == nil && parsedMinutes > 0 {
+		d := time.Duration(parsedMinutes) * time.Minute
+		return &d
+	}
+
+	log.Warnf("invalid %s value %q: expected a Go duration such as 30m or 1h", lazyconn.EnvInactivityThreshold, envValue)
+	return nil
 }

client/internal/conn_mgr_test.go

@@ -0,0 +1,141 @@
+package internal
+
+import (
+	"context"
+	"net"
+	"net/netip"
+	"os"
+	"sync"
+	"testing"
+	"time"
+
+	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
+
+	"github.com/netbirdio/netbird/client/iface/wgaddr"
+	"github.com/netbirdio/netbird/client/internal/lazyconn"
+	"github.com/netbirdio/netbird/client/internal/peer"
+	"github.com/netbirdio/netbird/client/internal/peerstore"
+	"github.com/netbirdio/netbird/monotime"
+)
+
+func TestResolveLazyForce(t *testing.T) {
+	tests := []struct {
+		name   string
+		env    string
+		envSet bool
+		mdm    lazyconn.State
+		want   lazyForce
+	}{
+		{name: "env unset, mdm unset -> defer to management", mdm: lazyconn.StateUnset, want: lazyForceNone},
+		{name: "env on -> force on", env: "on", envSet: true, mdm: lazyconn.StateUnset, want: lazyForceOn},
+		{name: "env off -> force off", env: "off", envSet: true, mdm: lazyconn.StateUnset, want: lazyForceOff},
+		{name: "env unset, mdm on -> force on", mdm: lazyconn.StateOn, want: lazyForceOn},
+		{name: "env unset, mdm off -> force off", mdm: lazyconn.StateOff, want: lazyForceOff},
+		{name: "env on beats mdm off", env: "on", envSet: true, mdm: lazyconn.StateOff, want: lazyForceOn},
+		{name: "env off beats mdm on", env: "off", envSet: true, mdm: lazyconn.StateOn, want: lazyForceOff},
+		{name: "unrecognized env, mdm on -> mdm wins", env: "auto", envSet: true, mdm: lazyconn.StateOn, want: lazyForceOn},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Setenv(lazyconn.EnvLazyConn, tt.env)
+			if !tt.envSet {
+				os.Unsetenv(lazyconn.EnvLazyConn)
+			}
+
+			if got := resolveLazyForce(tt.mdm); got != tt.want {
+				t.Fatalf("resolveLazyForce(%v) = %v, want %v", tt.mdm, got, tt.want)
+			}
+		})
+	}
+}
+
+type mockLazyWGIface struct{}
+
+func (mockLazyWGIface) RemovePeer(string) error { return nil }
+func (mockLazyWGIface) UpdatePeer(string, []netip.Prefix, time.Duration, *net.UDPAddr, *wgtypes.Key) error {
+	return nil
+}
+func (mockLazyWGIface) IsUserspaceBind() bool                    { return false }
+func (mockLazyWGIface) Address() wgaddr.Address                  { return wgaddr.Address{} }
+func (mockLazyWGIface) LastActivities() map[string]monotime.Time { return nil }
+func (mockLazyWGIface) MTU() uint16                              { return 1280 }
+
+// TestConnMgr_ActivatePeerConcurrentWithLifecycle exercises ActivatePeer from
+// non-engine goroutines (the DNS warm-up path) racing the manager lifecycle,
+// which stays on the engine loop. Run with -race: it fails if ActivatePeer
+// still requires engine.syncMsgMux for safety.
+func TestConnMgr_ActivatePeerConcurrentWithLifecycle(t *testing.T) {
+	t.Setenv(lazyconn.EnvLazyConn, "on")
+
+	status := peer.NewRecorder("https://mgm")
+	store := peerstore.NewConnStore()
+	connMgr := NewConnMgr(&EngineConfig{}, status, store, mockLazyWGIface{})
+
+	conn := newTestPeerConn(t, "peerA")
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	connMgr.Start(ctx)
+
+	done := make(chan struct{})
+	var wg sync.WaitGroup
+	for range 4 {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			for {
+				select {
+				case <-done:
+					return
+				default:
+					connMgr.ActivatePeer(ctx, conn)
+				}
+			}
+		}()
+	}
+
+	// Let the activators spin against the started manager, then tear it down
+	// underneath them and let them spin against the stopped manager.
+	time.Sleep(100 * time.Millisecond)
+	connMgr.Close()
+	time.Sleep(50 * time.Millisecond)
+
+	close(done)
+	wg.Wait()
+}
+
+func TestInactivityThresholdEnv(t *testing.T) {
+	tests := []struct {
+		name string
+		val  string
+		want *time.Duration
+	}{
+		{name: "unset", val: "", want: nil},
+		{name: "go duration minutes", val: "30m", want: durPtr(30 * time.Minute)},
+		{name: "go duration hours", val: "1h", want: durPtr(time.Hour)},
+		{name: "go duration seconds", val: "90s", want: durPtr(90 * time.Second)},
+		{name: "bare integer is minutes (backwards compat)", val: "5", want: durPtr(5 * time.Minute)},
+		{name: "zero duration", val: "0s", want: nil},
+		{name: "zero integer", val: "0", want: nil},
+		{name: "negative duration", val: "-5m", want: nil},
+		{name: "garbage", val: "abc", want: nil},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Setenv(lazyconn.EnvInactivityThreshold, tc.val)
+			got := inactivityThresholdEnv()
+			switch {
+			case tc.want == nil && got != nil:
+				t.Fatalf("want nil, got %v", *got)
+			case tc.want != nil && got == nil:
+				t.Fatalf("want %v, got nil", *tc.want)
+			case tc.want != nil && *got != *tc.want:
+				t.Fatalf("want %v, got %v", *tc.want, *got)
+			}
+		})
+	}
+}
+
+func durPtr(d time.Duration) *time.Duration { return &d }

client/internal/connect.go

@@ -11,6 +11,7 @@ import (
 	"runtime/debug"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/cenkalti/backoff/v4"
@@ -26,15 +27,19 @@ import (
 	"github.com/netbirdio/netbird/client/iface/device"
 	"github.com/netbirdio/netbird/client/iface/netstack"
 	"github.com/netbirdio/netbird/client/internal/dns"
+	"github.com/netbirdio/netbird/client/internal/lazyconn"
 	"github.com/netbirdio/netbird/client/internal/listener"
 	"github.com/netbirdio/netbird/client/internal/metrics"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/client/internal/profilemanager"
 	"github.com/netbirdio/netbird/client/internal/statemanager"
 	"github.com/netbirdio/netbird/client/internal/stdnet"
+	"github.com/netbirdio/netbird/client/internal/tunnelnotifier"
 	"github.com/netbirdio/netbird/client/internal/updater"
 	"github.com/netbirdio/netbird/client/internal/updater/installer"
 	nbnet "github.com/netbirdio/netbird/client/net"
+	"github.com/netbirdio/netbird/client/netstate"
+	"github.com/netbirdio/netbird/client/netsweep"
 	cProto "github.com/netbirdio/netbird/client/proto"
 	"github.com/netbirdio/netbird/client/ssh"
 	sshconfig "github.com/netbirdio/netbird/client/ssh/config"
@@ -54,6 +59,10 @@ var androidRunOverride func(c *ConnectClient, runningChan chan struct{}, logPath
 
 type ConnectClient struct {
 	ctx            context.Context
+	runCancel      context.CancelFunc
+	runExited      chan struct{}
+	runOnce        sync.Once
+	runStarted     atomic.Bool
 	config         *profilemanager.Config
 	statusRecorder *peer.Status
 
@@ -63,19 +72,53 @@ type ConnectClient struct {
 	updateManager *updater.Manager
 
 	persistSyncResponse bool
+
+	// netState gates every reconnection loop on OS-reported network
+	// availability. Nil (the default) disables gating; mobile platforms
+	// inject it via WithNetworkState.
+	netState *netstate.State
+
+	// sweeper cuts the management, signal and relay connections on network
+	// change; nil disables it.
+	sweeper *netsweep.Sweeper
+}
+
+// ConnectClientOption configures optional ConnectClient behavior.
+type ConnectClientOption func(*ConnectClient)
+
+// WithNetworkState injects the OS network availability state that gates every
+// reconnection loop; without it gating is disabled.
+func WithNetworkState(netState *netstate.State) ConnectClientOption {
+	return func(c *ConnectClient) { c.netState = netState }
+}
+
+// WithSweeper injects the network change sweeper.
+func WithSweeper(sweeper *netsweep.Sweeper) ConnectClientOption {
+	return func(c *ConnectClient) { c.sweeper = sweeper }
 }
 
 func NewConnectClient(
 	ctx context.Context,
 	config *profilemanager.Config,
 	statusRecorder *peer.Status,
+	opts ...ConnectClientOption,
 ) *ConnectClient {
-	return &ConnectClient{
-		ctx:            ctx,
+	// Derive the run context here so Stop owns the cancel that unblocks the run
+	// loop. runCancel is set once at construction, so Stop can call it without
+	// racing the run loop's startup. Callers therefore need not cancel before Stop.
+	runCtx, runCancel := context.WithCancel(ctx)
+	c := &ConnectClient{
+		ctx:            runCtx,
+		runCancel:      runCancel,
+		runExited:      make(chan struct{}),
 		config:         config,
 		statusRecorder: statusRecorder,
 		engineMutex:    sync.Mutex{},
 	}
+	for _, opt := range opts {
+		opt(c)
+	}
+	return c
 }
 
 func (c *ConnectClient) SetUpdateManager(um *updater.Manager) {
@@ -100,11 +143,14 @@ func (c *ConnectClient) RunOnAndroid(
 	stateFilePath string,
 	cacheDir string,
 ) error {
+	notifier := tunnelnotifier.New(networkChangeListener, nil)
+	defer notifier.Close()
+
 	// in case of non Android os these variables will be nil
 	mobileDependency := MobileDependency{
 		TunAdapter:            tunAdapter,
 		IFaceDiscover:         iFaceDiscover,
-		NetworkChangeListener: networkChangeListener,
+		NetworkChangeListener: notifier,
 		HostDNSAddresses:      dnsAddresses,
 		DnsReadyListener:      dnsReadyListener,
 		StateFilePath:         stateFilePath,
@@ -118,20 +164,31 @@ func (c *ConnectClient) RunOniOS(
 	networkChangeListener listener.NetworkChangeListener,
 	dnsManager dns.IosDnsManager,
 	stateFilePath string,
+	cacheDir string,
+	logFilePath string,
 ) error {
 	// Set GC percent to 5% to reduce memory usage as iOS only allows 50MB of memory for the extension.
 	debug.SetGCPercent(5)
 
+	notifier := tunnelnotifier.New(networkChangeListener, dnsManager)
+	defer notifier.Close()
+
 	mobileDependency := MobileDependency{
 		FileDescriptor:        fileDescriptor,
-		NetworkChangeListener: networkChangeListener,
-		DnsManager:            dnsManager,
+		NetworkChangeListener: notifier,
+		DnsManager:            notifier,
 		StateFilePath:         stateFilePath,
+		TempDir:               cacheDir,
 	}
-	return c.run(mobileDependency, nil, "")
+	return c.run(mobileDependency, nil, logFilePath)
 }
 
 func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan struct{}, logPath string) error {
+	// Mark the loop as started and signal exit on return so Stop can wait for
+	// the loop to finish (and skip the wait if the loop never ran).
+	c.runStarted.Store(true)
+	defer c.runOnce.Do(func() { close(c.runExited) })
+
 	defer func() {
 		if r := recover(); r != nil {
 			rec := c.statusRecorder
@@ -237,13 +294,23 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		log.Errorf("failed to clean up temporary installer file: %v", err)
 	}
 
-	defer c.statusRecorder.ClientStop()
+	defer func() {
+		c.statusRecorder.SetSessionExpiresAt(time.Time{})
+		c.statusRecorder.ClientStop()
+	}()
 	operation := func() error {
 		// if context cancelled we not start new backoff cycle
 		if c.ctx.Err() != nil {
 			return nil
 		}
 
+		// suspend connection attempts while the OS reports no usable network
+		if waited, err := c.netState.Wait(c.ctx); err != nil {
+			return nil
+		} else if waited {
+			backOff.Reset()
+		}
+
 		state.Set(StatusConnecting)
 
 		engineCtx, cancel := context.WithCancel(c.ctx)
@@ -255,8 +322,18 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		}()
 
 		log.Debugf("connecting to the Management service %s", c.config.ManagementURL.Host)
-		mgmClient, err := mgm.NewClient(engineCtx, c.config.ManagementURL.Host, myPrivateKey, mgmTlsEnabled)
+		mgmClient, err := mgm.NewClient(engineCtx, c.config.ManagementURL.Host, myPrivateKey, mgmTlsEnabled,
+			mgm.WithNetworkState(c.netState), mgm.WithSweeper(c.sweeper))
 		if err != nil {
+			// On daemon shutdown / Down() the parent context is cancelled
+			// and the dial fails with "context canceled". Wrapping that
+			// into state would leave the snapshot stuck at Connecting+err
+			// until the backoff loop wakes up — instead let the operation
+			// return cleanly so the deferred state.Set(StatusIdle) takes
+			// effect on the next iteration.
+			if c.ctx.Err() != nil {
+				return nil
+			}
 			return wrapErr(gstatus.Errorf(codes.FailedPrecondition, "failed connecting to Management Service : %s", err))
 		}
 		mgmNotifier := statusRecorderToMgmConnStateNotifier(c.statusRecorder)
@@ -287,7 +364,7 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 			log.Debug(err)
 			if s, ok := gstatus.FromError(err); ok && (s.Code() == codes.PermissionDenied) {
 				state.Set(StatusNeedsLogin)
-				_ = c.Stop()
+				c.runCancel()
 				return backoff.Permanent(wrapErr(err)) // unrecoverable error
 			}
 			return wrapErr(err)
@@ -295,6 +372,10 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		c.clientMetrics.RecordLoginDuration(engineCtx, time.Since(loginStarted), true)
 		c.statusRecorder.MarkManagementConnected()
 
+		if metricsConfig := loginResp.GetNetbirdConfig().GetMetrics(); metricsConfig != nil {
+			c.clientMetrics.UpdatePushFromMgm(c.ctx, metricsConfig.GetEnabled())
+		}
+
 		localPeerState := peer.LocalPeerState{
 			IP:              loginResp.GetPeerConfig().GetAddress(),
 			PubKey:          myPrivateKey.PublicKey().String(),
@@ -317,7 +398,7 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		}()
 
 		// with the global Netbird config in hand connect (just a connection, no stream yet) Signal
-		signalClient, err := connectToSignal(engineCtx, loginResp.GetNetbirdConfig(), myPrivateKey)
+		signalClient, err := connectToSignal(engineCtx, loginResp.GetNetbirdConfig(), myPrivateKey, c.netState, c.sweeper)
 		if err != nil {
 			log.Error(err)
 			return wrapErr(err)
@@ -353,7 +434,8 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 			engineConfig.StateDir = filepath.Dir(path)
 		}
 
-		relayManager := relayClient.NewManager(engineCtx, relayURLs, myPrivateKey.PublicKey().String(), engineConfig.MTU)
+		relayManager := relayClient.NewManager(engineCtx, relayURLs, myPrivateKey.PublicKey().String(), engineConfig.MTU,
+			relayClient.WithNetworkState(c.netState), relayClient.WithSweeper(c.sweeper))
 		c.statusRecorder.SetRelayMgr(relayManager)
 		if len(relayURLs) > 0 {
 			if token != nil {
@@ -380,6 +462,8 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 			StateManager:   stateManager,
 			UpdateManager:  c.updateManager,
 			ClientMetrics:  c.clientMetrics,
+			MetricsCtx:     c.ctx,
+			NetState:       c.netState,
 		}, mobileDependency)
 		engine.SetSyncResponsePersistence(c.persistSyncResponse)
 		c.engine = engine
@@ -390,6 +474,10 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 			return wrapErr(err)
 		}
 
+		// Seed the session-expiry deadline from the LoginResponse. Subsequent
+		// changes flow in through SyncResponse and are applied in handleSync.
+		engine.ApplySessionDeadline(loginResp.GetSessionExpiresAt())
+
 		log.Infof("Netbird engine started, the IP is: %s", peerConfig.GetAddress())
 		state.Set(StatusConnected)
 
@@ -407,14 +495,10 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 		c.engine = nil
 		c.engineMutex.Unlock()
 
-		// todo: consider to remove this condition. Is not thread safe.
-		// We should always call Stop(), but we need to verify that it is idempotent
-		if engine.wgInterface != nil {
-			log.Infof("ensuring %s is removed, Netbird engine context cancelled", engine.wgInterface.Name())
+		log.Infof("ensuring wg interface is removed, Netbird engine context cancelled")
 
-			if err := engine.Stop(); err != nil {
-				log.Errorf("Failed to stop engine: %v", err)
-			}
+		if err := engine.Stop(); err != nil {
+			log.Errorf("Failed to stop engine: %v", err)
 		}
 		c.statusRecorder.ClientTeardown()
 
@@ -430,12 +514,26 @@ func (c *ConnectClient) run(mobileDependency MobileDependency, runningChan chan
 	}
 
 	c.statusRecorder.ClientStart()
-	err = backoff.Retry(operation, backOff)
+	// Wrap the backoff with c.ctx so Down()/actCancel propagates into the
+	// inter-attempt sleep — otherwise a 15s MaxInterval can keep the retry
+	// loop alive long after the caller asked to give up, leaving the
+	// status stream stuck at Connecting.
+	err = backoff.Retry(operation, backoff.WithContext(backOff, c.ctx))
 	if err != nil {
+		// Once the client context is cancelled backoff.WithContext surfaces the
+		// bare context error, and any attempt torn down mid-flight reports the
+		// same. That cancellation is the caller asking us to stop (Stop, Down or
+		// an engine restart), so exit cleanly instead of handing back a failure
+		// the caller would have to distinguish from a real one.
+		if c.ctx.Err() != nil && errors.Is(err, context.Canceled) {
+			log.Info("exiting client retry loop, context cancelled")
+			return nil
+		}
+
 		log.Debugf("exiting client retry loop due to unrecoverable error: %s", err)
 		if s, ok := gstatus.FromError(err); ok && (s.Code() == codes.PermissionDenied) {
 			state.Set(StatusNeedsLogin)
-			_ = c.Stop()
+			c.runCancel()
 		}
 		return err
 	}
@@ -513,11 +611,9 @@ func (c *ConnectClient) Status() StatusType {
 }
 
 func (c *ConnectClient) Stop() error {
-	engine := c.Engine()
-	if engine != nil {
-		if err := engine.Stop(); err != nil {
-			return fmt.Errorf("stop engine: %w", err)
-		}
+	c.runCancel()
+	if c.runStarted.Load() {
+		<-c.runExited
 	}
 	return nil
 }
@@ -582,8 +678,9 @@ func createEngineConfig(key wgtypes.Key, config *profilemanager.Config, peerConf
 		BlockLANAccess:      config.BlockLANAccess,
 		BlockInbound:        config.BlockInbound,
 		DisableIPv6:         config.DisableIPv6,
+		SyncMessageVersion:  config.SyncMessageVersion,
 
-		LazyConnectionEnabled: config.LazyConnectionEnabled,
+		LazyConnection: lazyconn.ParseState(config.LazyConnection),
 
 		MTU:     selectMTU(config.MTU, peerConfig.Mtu),
 		LogPath: logPath,
@@ -626,7 +723,7 @@ func selectMTU(localMTU uint16, peerMTU int32) uint16 {
 }
 
 // connectToSignal creates Signal Service client and established a connection
-func connectToSignal(ctx context.Context, wtConfig *mgmProto.NetbirdConfig, ourPrivateKey wgtypes.Key) (*signal.GrpcClient, error) {
+func connectToSignal(ctx context.Context, wtConfig *mgmProto.NetbirdConfig, ourPrivateKey wgtypes.Key, netState *netstate.State, sweeper *netsweep.Sweeper) (*signal.GrpcClient, error) {
 	var sigTLSEnabled bool
 	if wtConfig.Signal.Protocol == mgmProto.HostConfig_HTTPS {
 		sigTLSEnabled = true
@@ -634,7 +731,8 @@ func connectToSignal(ctx context.Context, wtConfig *mgmProto.NetbirdConfig, ourP
 		sigTLSEnabled = false
 	}
 
-	signalClient, err := signal.NewClient(ctx, wtConfig.Signal.Uri, ourPrivateKey, sigTLSEnabled)
+	signalClient, err := signal.NewClient(ctx, wtConfig.Signal.Uri, ourPrivateKey, sigTLSEnabled,
+		signal.WithNetworkState(netState), signal.WithSweeper(sweeper))
 	if err != nil {
 		log.Errorf("error while connecting to the Signal Exchange Service %s: %s", wtConfig.Signal.Uri, err)
 		return nil, gstatus.Errorf(codes.FailedPrecondition, "failed connecting to Signal Service : %s", err)
@@ -657,7 +755,7 @@ func loginToManagement(ctx context.Context, client mgm.Client, pubSSHKey []byte,
 		config.BlockLANAccess,
 		config.BlockInbound,
 		config.DisableIPv6,
-		config.LazyConnectionEnabled,
+		config.SyncMessageVersion,
 		config.EnableSSHRoot,
 		config.EnableSSHSFTP,
 		config.EnableSSHLocalPortForwarding,

client/internal/daemonaddr/owner.go

@@ -0,0 +1,15 @@
+package daemonaddr
+
+// DaemonRunsAsSelf reports whether the daemon listening at addr runs as this very
+// user. That is what makes an unprivileged daemon authorize this process for the
+// changes it otherwise restricts to root or an administrator, so a client can tell
+// up front whether those controls are usable instead of letting a save fail.
+//
+// It is answered from the ownership of the socket or pipe the daemon created, so it
+// costs no round trip and needs no cooperation from the daemon. Ownership that
+// cannot be read is reported as false, including for a TCP address, so a caller
+// reading this as "the daemon would allow it" fails closed. The daemon remains the
+// only thing that authorizes anything: this only decides what a client offers.
+func DaemonRunsAsSelf(addr string) bool {
+	return daemonRunsAsSelf(addr)
+}

client/internal/daemonaddr/owner_unix.go

@@ -0,0 +1,40 @@
+//go:build !windows
+
+package daemonaddr
+
+import (
+	"os"
+	"strings"
+	"syscall"
+
+	log "github.com/sirupsen/logrus"
+)
+
+// daemonRunsAsSelf compares the owner of the daemon's Unix socket with this
+// process's uid. Root is not treated specially here: a root caller is privileged
+// on its own merits, and a root-owned socket says nothing about the caller.
+func daemonRunsAsSelf(addr string) bool {
+	path, ok := strings.CutPrefix(addr, "unix://")
+	if !ok {
+		return false
+	}
+
+	info, err := os.Stat(path)
+	if err != nil {
+		log.Debugf("stat daemon socket %s: %v", path, err)
+		return false
+	}
+
+	// Only a socket says anything about a daemon. A directory or a leftover
+	// regular file at that path is not one, and reading it as "the daemon runs as
+	// us" would offer controls the daemon then refuses.
+	if info.Mode()&os.ModeSocket == 0 {
+		return false
+	}
+
+	stat, ok := info.Sys().(*syscall.Stat_t)
+	if !ok {
+		return false
+	}
+	return stat.Uid == uint32(os.Getuid())
+}

client/internal/daemonaddr/owner_unix_test.go

@@ -0,0 +1,62 @@
+//go:build !windows
+
+package daemonaddr
+
+import (
+	"net"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+// A socket this user created means the daemon runs as this user, which is the
+// rootless case where the daemon delegates its authority to its own identity.
+func TestDaemonRunsAsSelf_OwnSocket(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "netbird.sock")
+	ln, err := net.Listen("unix", path)
+	if err != nil {
+		t.Fatalf("listen: %v", err)
+	}
+	t.Cleanup(func() {
+		if err := ln.Close(); err != nil {
+			t.Logf("close listener: %v", err)
+		}
+	})
+
+	if !DaemonRunsAsSelf("unix://" + path) {
+		t.Error("a socket owned by this user must count as the daemon running as us")
+	}
+}
+
+// Everything that is not a readable socket of ours has to answer false, because
+// the caller reads a true as "the daemon would authorize me".
+func TestDaemonRunsAsSelf_FailsClosed(t *testing.T) {
+	dir := t.TempDir()
+
+	// A socket owned by another user, which is what a root-run daemon looks like
+	// to an unprivileged client. Only assertable when we are not root ourselves.
+	rootOwned := "unix:///var/run/netbird.sock"
+	if _, err := os.Stat("/var/run/netbird.sock"); err == nil && os.Getuid() != 0 {
+		if DaemonRunsAsSelf(rootOwned) {
+			t.Error("a socket owned by another user must not count as ours")
+		}
+	}
+
+	for name, addr := range map[string]string{
+		"missing socket":  "unix://" + filepath.Join(dir, "absent.sock"),
+		"tcp address":     "tcp://127.0.0.1:41731",
+		"named pipe":      "npipe://netbird",
+		"empty":           "",
+		"no scheme":       filepath.Join(dir, "absent.sock"),
+		"directory":       "unix://" + dir,
+		"unknown scheme":  "http://localhost:8080",
+		"scheme only":     "unix://",
+		"relative socket": "unix://netbird.sock",
+	} {
+		t.Run(name, func(t *testing.T) {
+			if DaemonRunsAsSelf(addr) {
+				t.Errorf("%q must not count as a daemon running as us", addr)
+			}
+		})
+	}
+}

client/internal/daemonaddr/owner_windows.go

@@ -0,0 +1,42 @@
+//go:build windows
+
+package daemonaddr
+
+import (
+	"context"
+	"strings"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/internal/ipcauth"
+)
+
+// daemonRunsAsSelf reads the owner of the daemon's pipe. A daemon running as the
+// service account owns its pipe as LocalSystem, and an elevated one as
+// BUILTIN\Administrators, so only a daemon the user started themselves matches.
+func daemonRunsAsSelf(addr string) bool {
+	name, ok := strings.CutPrefix(addr, pipeScheme)
+	if !ok {
+		return false
+	}
+
+	for _, path := range PipePaths(name) {
+		// Bounded: this runs on the UI's path for deciding which controls to
+		// offer, so a pipe that does not answer promptly must not stall it. A
+		// timeout leaves the caller unprivileged, which only disables controls.
+		ctx, cancel := context.WithTimeout(context.Background(), probeTimeout)
+		conn, err := dialPipe(ctx, path)
+		cancel()
+		if err != nil {
+			continue
+		}
+
+		owned := ipcauth.PipeOwnedBySelf(conn)
+		if cerr := conn.Close(); cerr != nil {
+			log.Debugf("close daemon pipe %s after ownership check: %v", path, cerr)
+		}
+		return owned
+	}
+
+	return false
+}

client/internal/daemonaddr/pipe.go

@@ -0,0 +1,103 @@
+package daemonaddr
+
+import (
+	"context"
+	"net"
+	"runtime"
+	"strings"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+)
+
+const (
+	// WindowsPipeAddr is the default daemon address on Windows. A named pipe
+	// carries the connecting process's token, which loopback TCP does not, so
+	// it is the only Windows transport on which the daemon can tell who is
+	// calling it.
+	WindowsPipeAddr = "npipe://netbird"
+
+	// legacyWindowsAddr is the loopback-TCP address the Windows daemon used
+	// before named-pipe support.
+	legacyWindowsAddr = "tcp://127.0.0.1:41731"
+
+	pipeScheme = "npipe://"
+
+	// protectedPrefix is the NPFS namespace in which only LocalSystem and
+	// members of BUILTIN\Administrators may create a pipe. A daemon running as
+	// the service account creates its pipe there so that an unprivileged process
+	// cannot pre-create the name, which would keep the daemon from starting and
+	// leave callers talking to the squatter. Opening such a pipe needs no
+	// privilege, so unprivileged clients still reach the daemon.
+	protectedPrefix = `ProtectedPrefix\Administrators\`
+)
+
+// DialTarget returns the gRPC dial target and transport options for a daemon
+// address. The npipe scheme needs a context dialer because gRPC has no
+// named-pipe resolver; unix and tcp are handled by gRPC itself.
+func DialTarget(addr string) (string, []grpc.DialOption) {
+	opts := []grpc.DialOption{grpc.WithTransportCredentials(insecure.NewCredentials())}
+
+	if name, ok := strings.CutPrefix(addr, pipeScheme); ok {
+		paths := PipePaths(name)
+		opts = append(opts, grpc.WithContextDialer(func(ctx context.Context, _ string) (net.Conn, error) {
+			return dialPipePaths(ctx, paths)
+		}))
+		return "passthrough:///netbird-daemon-pipe", opts
+	}
+
+	return strings.TrimPrefix(addr, "tcp://"), opts
+}
+
+// PipePath maps an npipe address name ("netbird", from "npipe://netbird") to a
+// Windows named-pipe path (\\.\pipe\netbird). A fully qualified path is left as
+// is.
+func PipePath(name string) string {
+	if strings.HasPrefix(name, `\\`) {
+		return name
+	}
+	return `\\.\pipe\` + name
+}
+
+// PipePaths returns the paths a daemon control pipe may live at for an npipe
+// address name, in the order both sides must try them: the protected name first,
+// then the plain one.
+//
+// The daemon serves the first it can create, which is the protected name when it
+// runs as the service account and the plain one when it runs as an ordinary user,
+// as it does in netstack mode. Clients therefore have to try both, and because a
+// client cannot tell from the name alone who created the pipe, the plain name is
+// only usable once the server's identity has been checked: see
+// verifyPipeServer.
+//
+// A fully qualified path is what the operator asked for and is used as is.
+func PipePaths(name string) []string {
+	if strings.HasPrefix(name, `\\`) {
+		return []string{name}
+	}
+	return []string{PipePath(protectedPrefix + name), PipePath(name)}
+}
+
+// IsProtectedPipePath reports whether a pipe path is in the namespace only an
+// administrator or LocalSystem can create in, which is what lets a client trust
+// such a pipe from its name alone.
+func IsProtectedPipePath(path string) bool {
+	return strings.HasPrefix(path, `\\.\pipe\`+protectedPrefix)
+}
+
+// MigrateLegacy upgrades the pre-named-pipe Windows daemon address to the named
+// pipe, reporting whether it rewrote the address. Existing installs persist the
+// daemon address, so without this an upgraded daemon would keep listening on
+// loopback TCP, where callers carry no identity and privileged operations would
+// have to be refused for everyone. Only the exact legacy default is rewritten:
+// a deliberately chosen custom address is left alone.
+func MigrateLegacy(addr string) (string, bool) {
+	return migrateLegacyForOS(runtime.GOOS, addr)
+}
+
+func migrateLegacyForOS(goos, addr string) (string, bool) {
+	if goos == "windows" && addr == legacyWindowsAddr {
+		return WindowsPipeAddr, true
+	}
+	return addr, false
+}

client/internal/daemonaddr/pipe_other.go

@@ -0,0 +1,15 @@
+//go:build !windows
+
+package daemonaddr
+
+import (
+	"context"
+	"fmt"
+	"net"
+)
+
+// dialPipePaths is Windows-only: no other platform serves the daemon on a named
+// pipe.
+func dialPipePaths(context.Context, []string) (net.Conn, error) {
+	return nil, fmt.Errorf("named pipes are only supported on Windows")
+}

client/internal/daemonaddr/pipe_test.go

@@ -0,0 +1,30 @@
+package daemonaddr
+
+import (
+	"slices"
+	"testing"
+)
+
+// The protected name must be tried before the plain one on both sides: it is the
+// one an unprivileged process cannot create, so preferring it is what keeps a
+// squatter from owning the name the service daemon would otherwise use.
+func TestPipePaths_PrefersTheProtectedName(t *testing.T) {
+	got := PipePaths("netbird")
+	want := []string{
+		`\\.\pipe\ProtectedPrefix\Administrators\netbird`,
+		`\\.\pipe\netbird`,
+	}
+	if !slices.Equal(got, want) {
+		t.Errorf("PipePaths = %q, want %q", got, want)
+	}
+}
+
+// An operator who passes a full path chose exactly one pipe, so neither side may
+// look anywhere else.
+func TestPipePaths_QualifiedPathIsUsedAsIs(t *testing.T) {
+	path := `\\.\pipe\custom-netbird`
+	got := PipePaths(path)
+	if !slices.Equal(got, []string{path}) {
+		t.Errorf("PipePaths = %q, want just %q", got, path)
+	}
+}

client/internal/daemonaddr/pipe_windows.go

@@ -0,0 +1,59 @@
+//go:build windows
+
+package daemonaddr
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net"
+
+	"github.com/Microsoft/go-winio"
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/windows"
+
+	"github.com/netbirdio/netbird/client/internal/ipcauth"
+)
+
+// dialPipePaths connects to the first path that answers with a pipe server this
+// client may trust, and returns the last error when none does.
+func dialPipePaths(ctx context.Context, paths []string) (net.Conn, error) {
+	var lastErr error
+	for _, path := range paths {
+		conn, err := dialPipe(ctx, path)
+		if err != nil {
+			log.Debugf("dial daemon pipe %s: %v", path, err)
+			lastErr = err
+			continue
+		}
+
+		// A pipe in the protected namespace could only have been created by an
+		// administrator or LocalSystem, so its name is the guarantee. Any other
+		// name has to be checked, because any local user can create one.
+		if !IsProtectedPipePath(path) {
+			if err := ipcauth.PipeServerTrusted(conn); err != nil {
+				if closeErr := conn.Close(); closeErr != nil {
+					log.Debugf("close untrusted pipe %s: %v", path, closeErr)
+				}
+				lastErr = fmt.Errorf("%s: %w", path, err)
+				continue
+			}
+		}
+
+		return conn, nil
+	}
+
+	if lastErr == nil {
+		lastErr = errors.New("no daemon pipe to connect to")
+	}
+	return nil, lastErr
+}
+
+// dialPipe connects to the daemon control pipe at SECURITY_IDENTIFICATION.
+// winio's plain DialPipe connects at SECURITY_ANONYMOUS, under which the daemon
+// cannot read the caller's token at all. Identification lets the daemon read the
+// caller's SID and groups without granting it the ability to act as the caller.
+func dialPipe(ctx context.Context, path string) (net.Conn, error) {
+	access := uint32(windows.GENERIC_READ | windows.GENERIC_WRITE)
+	return winio.DialPipeAccessImpLevel(ctx, path, access, winio.PipeImpLevelIdentification)
+}

client/internal/daemonaddr/resolve_pipe_other.go

@@ -0,0 +1,9 @@
+//go:build !windows
+
+package daemonaddr
+
+// ResolveDaemonAddr is a no-op off Windows, where there is no named-pipe
+// default to fall back from.
+func ResolveDaemonAddr(addr string) string {
+	return addr
+}

client/internal/daemonaddr/resolve_pipe_windows.go

@@ -0,0 +1,82 @@
+//go:build windows
+
+package daemonaddr
+
+import (
+	"net"
+	"strings"
+	"time"
+
+	"github.com/Microsoft/go-winio"
+	log "github.com/sirupsen/logrus"
+)
+
+// probeTimeout bounds each transport probe. Both are local, so a daemon that is
+// listening answers immediately and one that is not fails immediately.
+const probeTimeout = 300 * time.Millisecond
+
+// ResolveDaemonAddr keeps a client on the named pipe and never silently moves it
+// off. When the pipe does not answer it checks the legacy loopback TCP address, so
+// a client meeting a daemon that has not restarted since the upgrade can say what
+// is wrong, but it does not connect there.
+//
+// Using that address automatically would be a downgrade the user never asked for:
+// any local process can bind 127.0.0.1 while the daemon is not listening, and the
+// transport carries no caller identity, so a client that accepted whatever answered
+// would hand a setup key, a pre-shared key or an SSO prompt to a local impostor. An
+// operator who needs the legacy address during the upgrade window can still pass
+// --daemon-addr explicitly, which is a deliberate choice and still refuses the
+// privileged operations.
+//
+// Only the pipe address is resolved. A custom address is left alone, though passing
+// --daemon-addr npipe://netbird explicitly is indistinguishable from the default
+// here, so it is treated the same way.
+func ResolveDaemonAddr(addr string) string {
+	if addr != WindowsPipeAddr {
+		return addr
+	}
+
+	for _, path := range PipePaths("netbird") {
+		if pipeAvailable(path) {
+			return addr
+		}
+	}
+
+	if tcpAvailable(legacyWindowsAddr) {
+		log.Warnf("the daemon is not serving %s, but something is listening on the legacy %s. "+
+			"Restart the NetBird service so it serves the pipe. That address is not used automatically: "+
+			"any local user can bind it and it carries no caller identity, so pass --daemon-addr %s "+
+			"explicitly if you accept that",
+			WindowsPipeAddr, legacyWindowsAddr, legacyWindowsAddr)
+	}
+
+	return addr
+}
+
+func pipeAvailable(path string) bool {
+	timeout := probeTimeout
+	conn, err := winio.DialPipe(path, &timeout)
+	if err != nil {
+		return false
+	}
+	if err := conn.Close(); err != nil {
+		log.Debugf("close daemon pipe probe: %v", err)
+	}
+	return true
+}
+
+func tcpAvailable(addr string) bool {
+	host := addr
+	if _, after, ok := strings.Cut(addr, "://"); ok {
+		host = after
+	}
+
+	conn, err := net.DialTimeout("tcp", host, probeTimeout)
+	if err != nil {
+		return false
+	}
+	if err := conn.Close(); err != nil {
+		log.Debugf("close daemon TCP probe: %v", err)
+	}
+	return true
+}

client/internal/debug/debug.go

@@ -34,9 +34,8 @@ import (
 	"github.com/netbirdio/netbird/shared/netiputil"
 )
 
-const readmeContent = `Netbird debug bundle
-This debug bundle contains the following files.
-If the --anonymize flag is set, the files are anonymized to protect sensitive information.
+const readmeContent = `This debug bundle contains the following files.
+If anonymization is enabled (--anonymize / --anonymize-level), the files are anonymized to protect sensitive information.
 
 status.txt: Anonymized status information of the NetBird client.
 client.log: Most recent, anonymized client log file of the NetBird client.
@@ -52,6 +51,7 @@ nftables.txt: Anonymized nftables rules with packet counters across all families
 sysctls.txt: Forwarding, reverse-path filter, source-validation, and conntrack accounting sysctl values that the NetBird client may read or modify, if --system-info flag was provided (Linux only).
 resolv.conf: DNS resolver configuration from /etc/resolv.conf (Unix systems only), if --system-info flag was provided.
 scutil_dns.txt: DNS configuration from scutil --dns (macOS only), if --system-info flag was provided.
+dns_windows.txt: Anonymized NRPT rules and policy table in effect, DNS client policy, and per-interface and per-adapter DNS configuration (Windows only), if --system-info flag was provided.
 resolved_domains.txt: Anonymized resolved domain IP addresses from the status recorder.
 config.txt: Anonymized configuration information of the NetBird client.
 network_map.json: Anonymized sync response containing peer configurations, routes, DNS settings, and firewall rules.
@@ -70,21 +70,34 @@ capture.pcap: Packet capture in pcap format. Only present when capture was runni
 
 
 Anonymization Process
-The files in this bundle have been anonymized to protect sensitive information. Here's how the anonymization was applied:
+The files in this bundle have been anonymized to protect sensitive information. The level applied to this bundle is recorded at the top of this file. Here's how the anonymization was applied:
 
 IP Addresses
 
-IPv4 addresses are replaced with addresses starting from 198.51.100.0
-IPv6 addresses are replaced with addresses starting from 100::
+Default level:
+- Public IPv4 addresses are replaced with addresses starting from 198.51.100.0
+- Public IPv6 addresses are replaced with addresses starting from 2001:db8:ffff::
+- IPv6 unique local addresses (fc00::/7) are anonymized as well: their random global ID uniquely identifies the network.
+- IP addresses from internal IPv4 ranges and well-known addresses are not anonymized (e.g. 8.8.8.8, 100.64.0.0/10, addresses starting with 192.168., 172.16., 10., 169.254., fe80::).
+
+Strict level (--anonymize-level strict), in addition to the default level:
+- Private (RFC 1918), CGNAT (100.64.0.0/10), and link-local (169.254.0.0/16, fe80::/10) addresses are anonymized too.
+- Internal IPv4 addresses are replaced with addresses starting from 198.18.0.0 and internal IPv6 addresses with addresses starting from 2001:db8:1::, so internal addresses remain distinguishable from public ones.
+- Addresses are mapped in order of first appearance: subnet structure, allocation scheme, and gateway conventions are not preserved. Prefix lengths of networks are preserved.
+- Peer names in front of NetBird domains are replaced with numbered placeholders (e.g. peer-1.netbird.cloud), and subdomain labels of other domains with host-N placeholders.
+- WireGuard public keys are replaced with consistent placeholder keys.
 
-IP addresses from non public ranges and well known addresses are not anonymized (e.g. 8.8.8.8, 100.64.0.0/10, addresses starting with 192.168., 172.16., 10., etc.).
 Reoccuring IP addresses are replaced with the same anonymized address.
 
 Note: The anonymized IP addresses in the status file do not match those in the log and routes files. However, the anonymized IP addresses are consistent within the status file and across the routes and log files.
 
+MAC Addresses
+MAC addresses are replaced at every anonymization level with consistent placeholders counting up from 02:00:00:00:00:01. Broadcast, multicast, and all-zero addresses are kept. At the default level a preserved IPv6 link-local address may still embed a MAC address (EUI-64); the strict level anonymizes those addresses.
+
 Domains
 All domain names (except for the netbird domains) are replaced with randomly generated strings ending in ".domain". Anonymized domains are consistent across all files in the bundle.
 Reoccuring domain names are replaced with the same anonymized domain.
+At the strict level, the peer name labels in front of netbird domains are anonymized as well.
 
 Sync Response
 The network_map.json file contains the following anonymized information:
@@ -225,6 +238,13 @@ scutil_dns.txt (macOS only):
 - Shows DNS configuration for all network interfaces
 - Includes search domains, nameservers, and DNS resolver settings
 - All IP addresses and domain names are anonymized
+
+dns_windows.txt (Windows only):
+- Lists the NRPT rules of both policy stores, the local one and the group policy one, marking the rules the client created
+- Follows them with the policy table the resolver has loaded, which differs from the rules while a change has not been picked up yet
+- Includes the DNS client group policy, the global TCP/IP and Dnscache parameters, and the DNS values of every interface that has any
+- Ends with the resolver configuration in effect per adapter, from GetAdaptersAddresses
+- All IP addresses and domain names are anonymized
 `
 
 const (
@@ -232,6 +252,12 @@ const (
 	errorLogFile  = "netbird.err"
 	stdoutLogFile = "netbird.out"
 
+	// Rotated-log glob prefixes (base log name without extension) passed to
+	// addRotatedLogFiles. The daemon's own log and the GUI log live in the same
+	// dir, so the prefixes must be disjoint to keep their rotated siblings apart.
+	clientLogPrefix = "client"
+	uiLogPrefix     = "gui-client"
+
 	darwinErrorLogPath  = "/var/log/netbird.out.log"
 	darwinStdoutLogPath = "/var/log/netbird.err.log"
 )
@@ -241,6 +267,20 @@ type MetricsExporter interface {
 	Export(w io.Writer) error
 }
 
+// LogOpener opens a log file for inclusion in the bundle. It exists so that log
+// files whose path was supplied by an IPC caller can be opened under a check
+// the daemon defines, instead of being opened with the daemon's privileges
+// unconditionally.
+type LogOpener func(path string) (*os.File, error)
+
+func openLogFile(path string) (*os.File, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, fmt.Errorf("open %s: %w", path, err)
+	}
+	return f, nil
+}
+
 type BundleGenerator struct {
 	anonymizer *anonymize.Anonymizer
 
@@ -249,7 +289,10 @@ type BundleGenerator struct {
 	statusRecorder *peer.Status
 	syncResponse   *mgmProto.SyncResponse
 	logPath        string
+	uiLogPath      string
+	uiLogOpener    LogOpener
 	tempDir        string
+	statePath      string
 	cpuProfile     []byte
 	capturePath    string
 	refreshStatus  func() // Optional callback to refresh status before bundle generation
@@ -258,6 +301,7 @@ type BundleGenerator struct {
 	cliVersion     string
 
 	anonymize         bool
+	anonymizeLevel    anonymize.Level
 	includeSystemInfo bool
 	logFileCount      uint32
 
@@ -265,7 +309,10 @@ type BundleGenerator struct {
 }
 
 type BundleConfig struct {
-	Anonymize         bool
+	Anonymize bool
+	// AnonymizeLevel selects how much the anonymizer redacts.
+	// anonymize.LevelStrict implies Anonymize.
+	AnonymizeLevel    anonymize.Level
 	IncludeSystemInfo bool
 	LogFileCount      uint32
 }
@@ -275,13 +322,21 @@ type GeneratorDependencies struct {
 	StatusRecorder *peer.Status
 	SyncResponse   *mgmProto.SyncResponse
 	LogPath        string
-	TempDir        string // Directory for temporary bundle zip files. If empty, os.TempDir() is used.
-	CPUProfile     []byte
-	CapturePath    string
-	RefreshStatus  func()
-	ClientMetrics  MetricsExporter
-	DaemonVersion  string
-	CliVersion     string
+	UILogPath      string // Absolute path to the desktop UI's gui-client.log, reported via RegisterUILog. Empty if no UI registered one.
+	// UILogOpener opens the UI log and its rotated siblings. The path comes from
+	// a local IPC caller, so the daemon must not open it with plain os.Open: the
+	// opener is where the caller's right to that file is enforced. Defaults to
+	// os.Open, which is only correct where the path is not caller-supplied
+	// (mobile).
+	UILogOpener   LogOpener
+	TempDir       string // Directory for temporary bundle zip files. If empty, os.TempDir() is used.
+	StatePath     string // Path to the state file. If empty, the ServiceManager default path is used.
+	CPUProfile    []byte
+	CapturePath   string
+	RefreshStatus func()
+	ClientMetrics MetricsExporter
+	DaemonVersion string
+	CliVersion    string
 }
 
 func NewBundleGenerator(deps GeneratorDependencies, cfg BundleConfig) *BundleGenerator {
@@ -291,14 +346,25 @@ func NewBundleGenerator(deps GeneratorDependencies, cfg BundleConfig) *BundleGen
 		logFileCount = 1
 	}
 
+	uiLogOpener := deps.UILogOpener
+	if uiLogOpener == nil {
+		uiLogOpener = openLogFile
+	}
+
+	anonymizer := anonymize.NewAnonymizer(anonymize.DefaultAddresses())
+	anonymizer.SetLevel(cfg.AnonymizeLevel)
+
 	return &BundleGenerator{
-		anonymizer: anonymize.NewAnonymizer(anonymize.DefaultAddresses()),
+		anonymizer: anonymizer,
 
 		internalConfig: deps.InternalConfig,
 		statusRecorder: deps.StatusRecorder,
 		syncResponse:   deps.SyncResponse,
 		logPath:        deps.LogPath,
+		uiLogPath:      deps.UILogPath,
+		uiLogOpener:    uiLogOpener,
 		tempDir:        deps.TempDir,
+		statePath:      deps.StatePath,
 		cpuProfile:     deps.CPUProfile,
 		capturePath:    deps.CapturePath,
 		refreshStatus:  deps.RefreshStatus,
@@ -306,7 +372,8 @@ func NewBundleGenerator(deps GeneratorDependencies, cfg BundleConfig) *BundleGen
 		daemonVersion:  deps.DaemonVersion,
 		cliVersion:     deps.CliVersion,
 
-		anonymize:         cfg.Anonymize,
+		anonymize:         cfg.Anonymize || cfg.AnonymizeLevel >= anonymize.LevelStrict,
+		anonymizeLevel:    cfg.AnonymizeLevel,
 		includeSystemInfo: cfg.IncludeSystemInfo,
 		logFileCount:      logFileCount,
 	}
@@ -408,6 +475,10 @@ func (g *BundleGenerator) createArchive() error {
 		log.Errorf("failed to add logs to debug bundle: %v", err)
 	}
 
+	if err := g.addUILog(); err != nil {
+		log.Errorf("failed to add UI log to debug bundle: %v", err)
+	}
+
 	if err := g.addUpdateLogs(); err != nil {
 		log.Errorf("failed to add updater logs: %v", err)
 	}
@@ -442,7 +513,13 @@ func (g *BundleGenerator) addSystemInfo() {
 }
 
 func (g *BundleGenerator) addReadme() error {
-	readmeReader := strings.NewReader(readmeContent)
+	level := "none (anonymization disabled)"
+	if g.anonymize {
+		level = g.anonymizeLevel.String()
+	}
+	header := fmt.Sprintf("Netbird debug bundle\nAnonymization level applied to this bundle: %s\n", level)
+
+	readmeReader := strings.NewReader(header + readmeContent)
 	if err := g.addFileToZip(readmeReader, "README.txt"); err != nil {
 		return fmt.Errorf("add README file to zip: %w", err)
 	}
@@ -463,11 +540,11 @@ func (g *BundleGenerator) addStatus() error {
 
 		fullStatus := g.statusRecorder.GetFullStatus()
 		protoFullStatus := nbstatus.ToProtoFullStatus(fullStatus)
-		protoFullStatus.Events = g.statusRecorder.GetEventHistory()
 		overview := nbstatus.ConvertToStatusOutputOverview(protoFullStatus, nbstatus.ConvertOptions{
-			Anonymize:     g.anonymize,
-			ProfileName:   profName,
-			DaemonVersion: g.daemonVersion,
+			Anonymize:      g.anonymize,
+			AnonymizeLevel: g.anonymizeLevel,
+			ProfileName:    profName,
+			DaemonVersion:  g.daemonVersion,
 		})
 		overview.CliVersion = g.cliVersion
 		statusOutput := overview.FullDetailSummary()
@@ -516,6 +593,14 @@ func (g *BundleGenerator) addConfig() error {
 		}
 	}
 
+	// Surface the set of MDM-enforced keys so a support engineer reading
+	// the bundle can tell which field values are user-set vs MDM-overridden.
+	// Same semantics as the mDMManagedFields list returned by the
+	// GetConfig RPC consumed by `netbird debug config`.
+	if managed := g.internalConfig.Policy().ManagedKeys(); len(managed) > 0 {
+		configContent.WriteString(fmt.Sprintf("MDMManagedFields: %v\n", managed))
+	}
+
 	configReader := strings.NewReader(configContent.String())
 	if err := g.addFileToZip(configReader, "config.txt"); err != nil {
 		return fmt.Errorf("add config file to zip: %w", err)
@@ -612,7 +697,7 @@ func (g *BundleGenerator) addCommonConfigFields(configContent *strings.Builder)
 	configContent.WriteString("NetBird Client Configuration:\n\n")
 
 	if key, err := wgtypes.ParseKey(g.internalConfig.PrivateKey); err == nil {
-		configContent.WriteString(fmt.Sprintf("PublicKey: %s\n", key.PublicKey().String()))
+		configContent.WriteString(fmt.Sprintf("PublicKey: %s\n", g.anonymizer.AnonymizeWGKey(key.PublicKey().String())))
 	}
 	configContent.WriteString(fmt.Sprintf("WgIface: %s\n", g.internalConfig.WgIface))
 	configContent.WriteString(fmt.Sprintf("WgPort: %d\n", g.internalConfig.WgPort))
@@ -652,6 +737,7 @@ func (g *BundleGenerator) addCommonConfigFields(configContent *strings.Builder)
 	configContent.WriteString(fmt.Sprintf("BlockLANAccess: %v\n", g.internalConfig.BlockLANAccess))
 	configContent.WriteString(fmt.Sprintf("BlockInbound: %v\n", g.internalConfig.BlockInbound))
 	configContent.WriteString(fmt.Sprintf("DisableIPv6: %v\n", g.internalConfig.DisableIPv6))
+	configContent.WriteString(fmt.Sprintf("SyncMessageVersion: %v\n", g.internalConfig.SyncMessageVersion))
 
 	if g.internalConfig.DisableNotifications != nil {
 		configContent.WriteString(fmt.Sprintf("DisableNotifications: %v\n", *g.internalConfig.DisableNotifications))
@@ -670,7 +756,7 @@ func (g *BundleGenerator) addCommonConfigFields(configContent *strings.Builder)
 		configContent.WriteString(fmt.Sprintf("ClientCertKeyPath: %s\n", g.internalConfig.ClientCertKeyPath))
 	}
 
-	configContent.WriteString(fmt.Sprintf("LazyConnectionEnabled: %v\n", g.internalConfig.LazyConnectionEnabled))
+	configContent.WriteString(fmt.Sprintf("LazyConnection: %q\n", g.internalConfig.LazyConnection))
 	configContent.WriteString(fmt.Sprintf("MTU: %d\n", g.internalConfig.MTU))
 }
 
@@ -842,8 +928,11 @@ func (g *BundleGenerator) maskSecrets() {
 }
 
 func (g *BundleGenerator) addStateFile() error {
-	sm := profilemanager.NewServiceManager("")
-	path := sm.GetStatePath()
+	path := g.statePath
+	if path == "" {
+		sm := profilemanager.NewServiceManager("")
+		path = sm.GetStatePath()
+	}
 	if path == "" {
 		return nil
 	}
@@ -898,6 +987,11 @@ func (g *BundleGenerator) addUpdateLogs() error {
 		}
 
 		baseName := filepath.Base(logFile)
+		data, err = g.anonymizeBytes(data)
+		if err != nil {
+			log.Warnf("skipping update log file %s: %v", baseName, err)
+			continue
+		}
 		if err := g.addFileToZip(bytes.NewReader(data), filepath.Join("update-logs", baseName)); err != nil {
 			return fmt.Errorf("add update log file %s to zip: %w", baseName, err)
 		}
@@ -925,6 +1019,13 @@ func (g *BundleGenerator) addCorruptedStateFiles() error {
 		}
 
 		fileName := filepath.Base(match)
+		// Corrupted state files usually fail structured JSON anonymization,
+		// so run them through the string anonymizer instead.
+		data, err = g.anonymizeBytes(data)
+		if err != nil {
+			log.Warnf("skipping corrupted state file %s: %v", fileName, err)
+			continue
+		}
 		if err := g.addFileToZip(bytes.NewReader(data), "corrupted_states/"+fileName); err != nil {
 			log.Warnf("Failed to add corrupted state file %s to zip: %v", fileName, err)
 			continue
@@ -936,6 +1037,27 @@ func (g *BundleGenerator) addCorruptedStateFiles() error {
 	return nil
 }
 
+// anonymizeBytes runs raw file content through the string anonymizer line by
+// line when anonymization is enabled. It errors instead of returning partial
+// content, so a caller never adds an unanonymized fallback to the bundle.
+func (g *BundleGenerator) anonymizeBytes(data []byte) ([]byte, error) {
+	if !g.anonymize {
+		return data, nil
+	}
+
+	var buf bytes.Buffer
+	scanner := bufio.NewScanner(bytes.NewReader(data))
+	scanner.Buffer(make([]byte, 1024*1024), 1024*1024)
+	for scanner.Scan() {
+		buf.WriteString(g.anonymizer.AnonymizeString(scanner.Text()))
+		buf.WriteByte('\n')
+	}
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("anonymize content: %w", err)
+	}
+	return buf.Bytes(), nil
+}
+
 func (g *BundleGenerator) addMetrics() error {
 	if g.clientMetrics == nil {
 		log.Debugf("skipping metrics in debug bundle: no metrics collector")
@@ -968,11 +1090,11 @@ func (g *BundleGenerator) addLogfile() error {
 
 	logDir := filepath.Dir(g.logPath)
 
-	if err := g.addSingleLogfile(g.logPath, clientLogFile); err != nil {
+	if err := g.addSingleLogfile(openLogFile, g.logPath, clientLogFile); err != nil {
 		return fmt.Errorf("add client log file to zip: %w", err)
 	}
 
-	g.addRotatedLogFiles(logDir)
+	g.addRotatedLogFiles(openLogFile, logDir, clientLogPrefix)
 
 	stdErrLogPath := filepath.Join(logDir, errorLogFile)
 	stdoutLogPath := filepath.Join(logDir, stdoutLogFile)
@@ -981,20 +1103,39 @@ func (g *BundleGenerator) addLogfile() error {
 		stdoutLogPath = darwinStdoutLogPath
 	}
 
-	if err := g.addSingleLogfile(stdErrLogPath, errorLogFile); err != nil {
+	if err := g.addSingleLogfile(openLogFile, stdErrLogPath, errorLogFile); err != nil {
 		log.Warnf("Failed to add %s to zip: %v", errorLogFile, err)
 	}
 
-	if err := g.addSingleLogfile(stdoutLogPath, stdoutLogFile); err != nil {
+	if err := g.addSingleLogfile(openLogFile, stdoutLogPath, stdoutLogFile); err != nil {
 		log.Warnf("Failed to add %s to zip: %v", stdoutLogFile, err)
 	}
 
 	return nil
 }
 
+// addUILog adds the desktop UI's gui-client.log (and its rotated siblings) to
+// the bundle. The path is reported by the UI via RegisterUILog; empty when no
+// UI registered one (e.g. headless / server). Missing file is non-fatal — the
+// UI only writes it while the daemon is in debug, so it's often absent.
+func (g *BundleGenerator) addUILog() error {
+	if g.uiLogPath == "" {
+		log.Debugf("no UI log path registered, skipping in debug bundle")
+		return nil
+	}
+
+	if err := g.addSingleLogfile(g.uiLogOpener, g.uiLogPath, configs.UILogFile); err != nil {
+		return fmt.Errorf("add UI log file to zip: %w", err)
+	}
+
+	g.addRotatedLogFiles(g.uiLogOpener, filepath.Dir(g.uiLogPath), uiLogPrefix)
+
+	return nil
+}
+
 // addSingleLogfile adds a single log file to the archive
-func (g *BundleGenerator) addSingleLogfile(logPath, targetName string) error {
-	logFile, err := os.Open(logPath)
+func (g *BundleGenerator) addSingleLogfile(open LogOpener, logPath, targetName string) error {
+	logFile, err := open(logPath)
 	if err != nil {
 		return fmt.Errorf("open log file %s: %w", targetName, err)
 	}
@@ -1019,8 +1160,8 @@ func (g *BundleGenerator) addSingleLogfile(logPath, targetName string) error {
 }
 
 // addSingleLogFileGz adds a single gzipped log file to the archive
-func (g *BundleGenerator) addSingleLogFileGz(logPath, targetName string) error {
-	f, err := os.Open(logPath)
+func (g *BundleGenerator) addSingleLogFileGz(open LogOpener, logPath, targetName string) error {
+	f, err := open(logPath)
 	if err != nil {
 		return fmt.Errorf("open gz log file %s: %w", targetName, err)
 	}
@@ -1064,14 +1205,16 @@ func (g *BundleGenerator) addSingleLogFileGz(logPath, targetName string) error {
 	return nil
 }
 
-// addRotatedLogFiles adds rotated log files to the bundle based on logFileCount
-func (g *BundleGenerator) addRotatedLogFiles(logDir string) {
+// addRotatedLogFiles adds rotated log files to the bundle based on logFileCount.
+// prefix is the base log name without extension (e.g. "client", "gui-client");
+// the glob matches both files rotated by us and by logrotate on linux.
+func (g *BundleGenerator) addRotatedLogFiles(open LogOpener, logDir, prefix string) {
 	if g.logFileCount == 0 {
 		return
 	}
 
-	// This regex will match both logs rotated by us and logrotate on linux
-	pattern := filepath.Join(logDir, "client*.log.*")
+	// This pattern matches both logs rotated by us and logrotate on linux
+	pattern := filepath.Join(logDir, prefix+"*.log.*")
 	files, err := filepath.Glob(pattern)
 	if err != nil {
 		log.Warnf("failed to glob rotated logs: %v", err)
@@ -1105,9 +1248,9 @@ func (g *BundleGenerator) addRotatedLogFiles(logDir string) {
 	for i := 0; i < maxFiles; i++ {
 		name := filepath.Base(files[i])
 		if strings.HasSuffix(name, ".gz") {
-			err = g.addSingleLogFileGz(files[i], name)
+			err = g.addSingleLogFileGz(open, files[i], name)
 		} else {
-			err = g.addSingleLogfile(files[i], name)
+			err = g.addSingleLogfile(open, files[i], name)
 		}
 		if err != nil {
 			log.Warnf("failed to add rotated log %s: %v", name, err)
@@ -1387,6 +1530,7 @@ func anonymizeRemotePeer(peer *mgmProto.RemotePeerConfig, anonymizer *anonymize.
 	}
 
 	peer.Fqdn = anonymizer.AnonymizeDomain(peer.Fqdn)
+	peer.WgPubKey = anonymizer.AnonymizeWGKey(peer.WgPubKey)
 
 	anonymizeSSHConfig(peer.SshConfig)
 }

client/internal/debug/debug_ios.go

@@ -0,0 +1,36 @@
+//go:build ios
+
+package debug
+
+import (
+	"path/filepath"
+
+	log "github.com/sirupsen/logrus"
+)
+
+// swiftLogFile is the Swift app log written by the iOS app into the same log
+// directory as the Go client log, so it can be collected into the bundle.
+const swiftLogFile = "swift-log.log"
+
+// addPlatformLog collects logs for the iOS debug bundle. iOS has no logcat or
+// systemd journal, so we rely on file-based logs. addLogfile handles the Go
+// client log (logPath) with rotation, the stderr/stdout companions and
+// anonymization. The iOS app writes its own Swift log into the same directory,
+// so we add it alongside the Go log.
+func (g *BundleGenerator) addPlatformLog() error {
+	if err := g.addLogfile(); err != nil {
+		return err
+	}
+
+	if g.logPath == "" {
+		return nil
+	}
+
+	swiftLogPath := filepath.Join(filepath.Dir(g.logPath), swiftLogFile)
+	if err := g.addSingleLogfile(openLogFile, swiftLogPath, swiftLogFile); err != nil {
+		// The Swift log is best-effort: the app may not have written it yet.
+		log.Warnf("failed to add %s to debug bundle: %v", swiftLogFile, err)
+	}
+
+	return nil
+}

client/internal/debug/debug_linux.go

@@ -844,6 +844,10 @@ func collectSysctls() string {
 		[]string{"net.ipv4.conf.all.src_valid_mark", "net.ipv4.conf.default.src_valid_mark"},
 		listInterfaceSysctls("ipv4", "src_valid_mark")...,
 	))
+	writeSysctlGroup(&builder, "accept_ra", append(
+		[]string{"net.ipv6.conf.all.accept_ra", "net.ipv6.conf.default.accept_ra"},
+		listInterfaceSysctls("ipv6", "accept_ra")...,
+	))
 	writeSysctlGroup(&builder, "conntrack", []string{
 		"net.netfilter.nf_conntrack_acct",
 		"net.netfilter.nf_conntrack_tcp_loose",

client/internal/debug/debug_logfiles_test.go

@@ -40,6 +40,25 @@ func TestAddRotatedLogFiles_PicksUpAllVariants(t *testing.T) {
 	require.NotContains(t, names, "other.log", "unrelated files should not be in bundle")
 }
 
+// TestAddRotatedLogFiles_GUIPrefix asserts the prefix parameter scopes the glob
+// to the GUI log: gui-client.log.* rotated siblings are picked up and the
+// daemon's own client.log.* are not (and vice versa, covered above). This is
+// the load-bearing check for the gui-client.log bundle collection — the old
+// "client*.log.*" glob would have missed gui-client rotations.
+func TestAddRotatedLogFiles_GUIPrefix(t *testing.T) {
+	dir := t.TempDir()
+
+	writeFile(t, filepath.Join(dir, "gui-client.log.1"), "gui rotated\n")
+	writeGzFile(t, filepath.Join(dir, "gui-client.log.2.gz"), "gui rotated gz\n")
+	writeFile(t, filepath.Join(dir, "client.log.1"), "daemon rotated\n")
+
+	names := runAddRotatedLogFilesPrefix(t, dir, "gui-client", 10)
+
+	require.Contains(t, names, "gui-client.log.1", "gui-client rotated file should be in bundle")
+	require.Contains(t, names, "gui-client.log.2.gz", "gui-client gz rotated file should be in bundle")
+	require.NotContains(t, names, "client.log.1", "daemon rotated file must not match the gui-client prefix")
+}
+
 // TestAddRotatedLogFiles_RespectsLogFileCount asserts that only the newest
 // logFileCount rotated files are bundled, ordered by mtime.
 func TestAddRotatedLogFiles_RespectsLogFileCount(t *testing.T) {
@@ -67,6 +86,10 @@ func TestAddRotatedLogFiles_RespectsLogFileCount(t *testing.T) {
 // runAddRotatedLogFiles calls addRotatedLogFiles against a fresh in-memory
 // zip writer and returns the set of entry names that ended up in the archive.
 func runAddRotatedLogFiles(t *testing.T, dir string, logFileCount uint32) map[string]struct{} {
+	return runAddRotatedLogFilesPrefix(t, dir, "client", logFileCount)
+}
+
+func runAddRotatedLogFilesPrefix(t *testing.T, dir, prefix string, logFileCount uint32) map[string]struct{} {
 	t.Helper()
 
 	var buf bytes.Buffer
@@ -74,7 +97,7 @@ func runAddRotatedLogFiles(t *testing.T, dir string, logFileCount uint32) map[st
 		archive:      zip.NewWriter(&buf),
 		logFileCount: logFileCount,
 	}
-	g.addRotatedLogFiles(dir)
+	g.addRotatedLogFiles(openLogFile, dir, prefix)
 	require.NoError(t, g.archive.Close())
 
 	zr, err := zip.NewReader(bytes.NewReader(buf.Bytes()), int64(buf.Len()))

client/internal/debug/debug_nonandroid.go

@@ -1,4 +1,4 @@
-//go:build !android
+//go:build !android && !ios
 
 package debug
 

client/internal/debug/debug_nonunix.go

@@ -1,4 +1,4 @@
-//go:build !unix
+//go:build !unix && !windows
 
 package debug
 

client/internal/debug/debug_test.go

@@ -843,6 +843,8 @@ func TestAddConfig_AllFieldsCovered(t *testing.T) {
 		"PreSharedKey":      "sensitive: WireGuard pre-shared key",
 		"SSHKey":            "sensitive: SSH private key",
 		"ClientCertKeyPair": "non-config: parsed cert pair, not serialized",
+		"Name":              "non-config: profile name is not needed for debug purposes",
+		"policy":            "non-config: in-memory MDM policy snapshot, surfaced via Config.Policy() / GetConfigResponse.MDMManagedFields",
 	}
 
 	mURL, _ := url.Parse("https://api.example.com:443")
@@ -883,8 +885,10 @@ func TestAddConfig_AllFieldsCovered(t *testing.T) {
 		DNSRouteInterval:              5 * time.Second,
 		ClientCertPath:                "/tmp/cert",
 		ClientCertKeyPath:             "/tmp/key",
-		LazyConnectionEnabled:         true,
+		LazyConnection:                "on",
 		MTU:                           1280,
+		DisableIPv6:                   true,
+		SyncMessageVersion:            func(v int) *int { return &v }(1),
 	}
 
 	for _, anonymize := range []bool{false, true} {

client/internal/debug/debug_windows.go

@@ -0,0 +1,443 @@
+//go:build windows
+
+package debug
+
+import (
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"net/netip"
+	"strings"
+	"unsafe"
+
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/windows"
+	"golang.org/x/sys/windows/registry"
+
+	nbdns "github.com/netbirdio/netbird/client/internal/dns"
+)
+
+const dnsInfoFileName = "dns_windows.txt"
+
+const (
+	gpoDNSClientRoot = `SOFTWARE\Policies\Microsoft\Windows NT\DNSClient`
+	tcpipParamsPath  = `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters`
+	dnscacheParams   = `SYSTEM\CurrentControlSet\Services\Dnscache\Parameters`
+)
+
+// interfaceDNSValues are the per-interface values that decide how a name is
+// resolved and registered. Everything the DNS host manager writes is in here,
+// so a bundle shows both what we set and what it replaced.
+var interfaceDNSValues = []string{
+	"NameServer",
+	"DhcpNameServer",
+	"Domain",
+	"DhcpDomain",
+	"SearchList",
+	"RegistrationEnabled",
+	"DisableDynamicUpdate",
+	"MaxNumberOfAddressesToRegister",
+	"EnableDHCP",
+}
+
+// addDNSInfo collects and adds DNS configuration information to the archive
+func (g *BundleGenerator) addDNSInfo() error {
+	if err := g.addFileToZip(strings.NewReader(g.collectDNSInfo()), dnsInfoFileName); err != nil {
+		return fmt.Errorf("add DNS info to zip: %w", err)
+	}
+
+	return nil
+}
+
+// collectDNSInfo renders the report. Everything below it reaches the platform
+// through COM and through lazily resolved procedures, which panic when a
+// procedure is missing rather than returning an error, and a debug bundle is not
+// allowed to take the daemon down. The panic is contained here, and whatever was
+// collected before it is kept and reported with it.
+func (g *BundleGenerator) collectDNSInfo() (content string) {
+	var sb strings.Builder
+
+	defer func() {
+		if r := recover(); r != nil {
+			log.Errorf("collecting Windows DNS configuration panicked: %v", r)
+			fmt.Fprintf(&sb, "\nerror: collection stopped: %v\n", r)
+		}
+		content = sb.String()
+	}()
+
+	sb.WriteString("Windows DNS configuration\n")
+	sb.WriteString("=========================\n")
+
+	adapters, adaptersErr := adapterAddresses()
+
+	g.writeNRPTRules(&sb, "NRPT rules, local policy store", nbdns.DNSPolicyConfigRoot)
+	g.writeNRPTRules(&sb, "NRPT rules, group policy store", nbdns.GPODNSPolicyConfigRoot)
+	g.writeEffectiveNRPTPolicies(&sb)
+	g.writeRegistryKey(&sb, "DNS client group policy", gpoDNSClientRoot)
+	g.writeRegistryKey(&sb, "Global TCP/IP parameters", tcpipParamsPath)
+	g.writeRegistryKey(&sb, "Dnscache parameters", dnscacheParams)
+	g.writeInterfaceDNS(&sb, "Per-interface DNS, IPv4", nbdns.InterfaceConfigPath, adapterNames(adapters))
+	g.writeInterfaceDNS(&sb, "Per-interface DNS, IPv6", nbdns.InterfaceConfigPathV6, adapterNames(adapters))
+	g.writeAdapterDNS(&sb, adapters, adaptersErr)
+
+	return sb.String()
+}
+
+// writeNRPTRules lists every rule in a policy store, ours and any other
+// product's, since a foreign rule for the same namespace decides resolution
+// just as ours does. Rules the client wrote are marked.
+func (g *BundleGenerator) writeNRPTRules(sb *strings.Builder, title, root string) {
+	writeSection(sb, title, root)
+
+	names, err := subKeyNames(root)
+	if err != nil {
+		fmt.Fprintf(sb, "error: %v\n", err)
+		return
+	}
+
+	if len(names) == 0 {
+		sb.WriteString("no rules\n")
+		return
+	}
+
+	for _, name := range names {
+		owner := ""
+		if strings.HasPrefix(strings.ToLower(name), strings.ToLower(nbdns.NRPTKeyPrefix)) {
+			owner = "  (netbird)"
+		}
+		fmt.Fprintf(sb, "%s%s\n", name, owner)
+		g.writeValues(sb, root+`\`+name, nil, "  ")
+	}
+}
+
+// writeEffectiveNRPTPolicies reports the table the resolver answers from, which
+// the registry cannot show: a rule is written before it is loaded, and it keeps
+// being enforced after its key is gone until the resolver reloads its policy.
+func (g *BundleGenerator) writeEffectiveNRPTPolicies(sb *strings.Builder) {
+	writeSection(sb, "NRPT policy table in effect", nrptPolicyClass+"."+nrptPolicyMethod+" in "+nrptPolicyNamespace)
+
+	entries, err := effectiveNRPTPolicies()
+	if err != nil {
+		fmt.Fprintf(sb, "error: %v\n", err)
+		return
+	}
+
+	if len(entries) == 0 {
+		sb.WriteString("no policies\n")
+		return
+	}
+
+	for _, entry := range entries {
+		fmt.Fprintf(sb, "%s\n", g.anonymizeValue("Namespace", entry.namespace))
+		for _, value := range entry.values {
+			fmt.Fprintf(sb, "  %s: %s\n", value.name, g.anonymizeValue(value.name, value.value))
+		}
+	}
+}
+
+// writeInterfaceDNS reports the DNS values of every interface that has any, so
+// the netbird interface can be compared against the physical ones. The registry
+// keys the values by GUID, so each is named from the adapter list; a GUID with
+// no adapter is a leftover key of an interface that no longer exists.
+func (g *BundleGenerator) writeInterfaceDNS(sb *strings.Builder, title, root string, names map[string]string) {
+	writeSection(sb, title, root)
+
+	guids, err := subKeyNames(root)
+	if err != nil {
+		fmt.Fprintf(sb, "error: %v\n", err)
+		return
+	}
+
+	var reported int
+	for _, guid := range guids {
+		var iface strings.Builder
+		g.writeValues(&iface, root+`\`+guid, interfaceDNSValues, "  ")
+		if iface.Len() == 0 {
+			continue
+		}
+
+		name, ok := names[strings.ToLower(guid)]
+		if !ok {
+			name = "no adapter with this GUID"
+		}
+
+		reported++
+		fmt.Fprintf(sb, "%s (%s)\n%s", guid, name, iface.String())
+	}
+
+	if reported == 0 {
+		sb.WriteString("no interface holds DNS values\n")
+	}
+}
+
+// writeRegistryKey reports the values of a single key, without its subkeys.
+func (g *BundleGenerator) writeRegistryKey(sb *strings.Builder, title, path string) {
+	writeSection(sb, title, path)
+
+	var values strings.Builder
+	g.writeValues(&values, path, nil, "")
+	if values.Len() == 0 {
+		sb.WriteString("no values\n")
+		return
+	}
+
+	sb.WriteString(values.String())
+}
+
+// writeValues renders the values of a key. A nil names list reports every
+// value, otherwise only those named and present.
+func (g *BundleGenerator) writeValues(sb *strings.Builder, path string, names []string, indent string) {
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, path, registry.QUERY_VALUE)
+	switch {
+	case errors.Is(err, registry.ErrNotExist), errors.Is(err, windows.ERROR_PATH_NOT_FOUND):
+		// an absent key is the normal state for the GPO store and for
+		// interfaces without DNS settings
+		log.Debugf("HKEY_LOCAL_MACHINE\\%s does not exist", path)
+		return
+	case err != nil:
+		fmt.Fprintf(sb, "%serror: open HKEY_LOCAL_MACHINE\\%s: %v\n", indent, path, err)
+		return
+	}
+	defer closeKey(k)
+
+	if names == nil {
+		names, err = k.ReadValueNames(-1)
+		if err != nil {
+			fmt.Fprintf(sb, "%serror: read value names: %v\n", indent, err)
+			return
+		}
+	}
+
+	for _, name := range names {
+		value, err := readRegistryValue(k, name)
+		switch {
+		case errors.Is(err, registry.ErrNotExist):
+			// the caller asks for a fixed set of values, most of which a
+			// given interface does not carry
+			continue
+		case err != nil:
+			// report rather than omit: a value that is there but cannot be
+			// read reads as unset otherwise
+			fmt.Fprintf(sb, "%s%s: error: %v\n", indent, name, err)
+			continue
+		}
+
+		fmt.Fprintf(sb, "%s%s: %s\n", indent, name, g.anonymizeValue(name, value))
+	}
+}
+
+// anonymizeValue redacts a registry value according to what its name says it
+// holds. Domains and addresses are handled per entry rather than by the string
+// pass: the pass only replaces domains something else in the bundle already
+// seeded, and its address regex would eat the digit labels of a reverse zone.
+func (g *BundleGenerator) anonymizeValue(name, value string) string {
+	if !g.anonymize || value == "" {
+		return value
+	}
+
+	switch {
+	case holdsDomains(name):
+		return joinValueEntries(splitValueEntries(value), g.anonymizeDomain)
+	case holdsAddresses(name):
+		return joinValueEntries(splitValueEntries(value), g.anonymizer.AnonymizeIPString)
+	default:
+		return g.anonymizer.AnonymizeString(value)
+	}
+}
+
+// holdsDomains reports whether a value name holds domains: the domain list of
+// an NRPT rule (Name) or of the policy table (Namespace), a search list, the
+// DNS suffix values of the TCP/IP and policy keys, which all end in "Domain"
+// (Domain, DhcpDomain, NV Domain, ICSDomain), and a proxy host name.
+func holdsDomains(name string) bool {
+	lower := strings.ToLower(name)
+	return lower == "name" || lower == "namespace" || lower == "searchlist" ||
+		strings.HasSuffix(lower, "domain") || strings.HasSuffix(lower, "proxyname")
+}
+
+// holdsAddresses reports whether a value name holds DNS server addresses
+// (NameServer, DhcpNameServer, GenericDNSServers, NameServers).
+func holdsAddresses(name string) bool {
+	lower := strings.ToLower(name)
+	return strings.Contains(lower, "nameserver") || strings.Contains(lower, "dnsserver")
+}
+
+// adapterNames maps adapter GUIDs, as the registry keys the interfaces, to the
+// names an operator sees.
+func adapterNames(adapters []*windows.IpAdapterAddresses) map[string]string {
+	names := make(map[string]string, len(adapters))
+	for _, adapter := range adapters {
+		guid := windows.BytePtrToString(adapter.AdapterName)
+		names[strings.ToLower(guid)] = windows.UTF16PtrToString(adapter.FriendlyName)
+	}
+	return names
+}
+
+// writeAdapterDNS reports the resolver configuration in effect per adapter,
+// which is what the resolver uses for a name no NRPT rule matches.
+func (g *BundleGenerator) writeAdapterDNS(sb *strings.Builder, adapters []*windows.IpAdapterAddresses, err error) {
+	writeSection(sb, "Adapter DNS configuration", "GetAdaptersAddresses")
+
+	if err != nil {
+		fmt.Fprintf(sb, "error: %v\n", err)
+		return
+	}
+
+	for _, adapter := range adapters {
+		name := windows.UTF16PtrToString(adapter.FriendlyName)
+		suffix := g.anonymizeDomain(windows.UTF16PtrToString(adapter.DnsSuffix))
+
+		fmt.Fprintf(sb, "%s (index %d, oper status %d)\n", name, adapter.IfIndex, adapter.OperStatus)
+		fmt.Fprintf(sb, "  DNS suffix: %s\n", suffix)
+
+		var servers []string
+		for server := adapter.FirstDnsServerAddress; server != nil; server = server.Next {
+			addr, ok := netip.AddrFromSlice(server.Address.IP())
+			if !ok {
+				continue
+			}
+
+			addr = addr.Unmap()
+			if g.anonymize {
+				addr = g.anonymizer.AnonymizeIP(addr)
+			}
+			servers = append(servers, addr.String())
+		}
+
+		fmt.Fprintf(sb, "  DNS servers: %s\n", strings.Join(servers, ", "))
+	}
+}
+
+// anonymizeDomain anonymizes a single domain, keeping the leading dot an NRPT
+// match domain carries.
+func (g *BundleGenerator) anonymizeDomain(entry string) string {
+	if !g.anonymize {
+		return entry
+	}
+
+	domain, dot := strings.CutPrefix(entry, ".")
+	if domain == "" {
+		return entry
+	}
+
+	anonymized := g.anonymizer.AnonymizeDomain(domain)
+	if dot {
+		anonymized = "." + anonymized
+	}
+	return anonymized
+}
+
+// splitValueEntries splits a registry value that holds a list. The separator
+// differs per value: a REG_MULTI_SZ arrives joined with ", ", a SearchList is
+// comma separated and a NameServer may use commas or spaces.
+func splitValueEntries(value string) []string {
+	return strings.FieldsFunc(value, func(r rune) bool {
+		return r == ',' || r == ';' || r == ' ' || r == '\t'
+	})
+}
+
+func joinValueEntries(entries []string, anonymize func(string) string) string {
+	for i, entry := range entries {
+		entries[i] = anonymize(entry)
+	}
+	return strings.Join(entries, ", ")
+}
+
+func writeSection(sb *strings.Builder, title, source string) {
+	fmt.Fprintf(sb, "\n%s\n%s\n%s\n", title, strings.Repeat("-", len(title)), source)
+}
+
+func subKeyNames(root string) ([]string, error) {
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, root, registry.ENUMERATE_SUB_KEYS)
+	if err != nil {
+		return nil, fmt.Errorf("open HKEY_LOCAL_MACHINE\\%s: %w", root, err)
+	}
+	defer closeKey(k)
+
+	names, err := k.ReadSubKeyNames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("read subkey names: %w", err)
+	}
+
+	return names, nil
+}
+
+// readRegistryValue renders a value as text regardless of its type, so an
+// unexpected type in a policy key still shows up instead of being dropped.
+func readRegistryValue(k registry.Key, name string) (string, error) {
+	_, valueType, err := k.GetValue(name, nil)
+	if err != nil {
+		return "", fmt.Errorf("get value %s: %w", name, err)
+	}
+
+	switch valueType {
+	case registry.SZ, registry.EXPAND_SZ:
+		value, _, err := k.GetStringValue(name)
+		if err != nil {
+			return "", fmt.Errorf("get string value %s: %w", name, err)
+		}
+		return value, nil
+	case registry.MULTI_SZ:
+		values, _, err := k.GetStringsValue(name)
+		if err != nil {
+			return "", fmt.Errorf("get strings value %s: %w", name, err)
+		}
+		return strings.Join(values, ", "), nil
+	case registry.DWORD, registry.QWORD:
+		value, _, err := k.GetIntegerValue(name)
+		if err != nil {
+			return "", fmt.Errorf("get integer value %s: %w", name, err)
+		}
+		return fmt.Sprintf("%d (0x%x)", value, value), nil
+	case registry.BINARY:
+		value, _, err := k.GetBinaryValue(name)
+		if err != nil {
+			return "", fmt.Errorf("get binary value %s: %w", name, err)
+		}
+		return hex.EncodeToString(value), nil
+	default:
+		return fmt.Sprintf("<unhandled registry type %d>", valueType), nil
+	}
+}
+
+// adapterAddresses returns the adapter list including DNS servers. The call
+// reports the size it needs, so grow the buffer and retry until it fits.
+func adapterAddresses() (adapters []*windows.IpAdapterAddresses, err error) {
+	// GetAdaptersAddresses is resolved on first use and panics when it is
+	// missing, so this reports it as an error and leaves the rest of the
+	// report intact.
+	defer func() {
+		if r := recover(); r != nil {
+			adapters, err = nil, fmt.Errorf("GetAdaptersAddresses: %v", r)
+		}
+	}()
+
+	const flags = windows.GAA_FLAG_SKIP_ANYCAST | windows.GAA_FLAG_SKIP_MULTICAST
+
+	size := uint32(15000)
+	for range 3 {
+		buf := make([]byte, size)
+		first := (*windows.IpAdapterAddresses)(unsafe.Pointer(&buf[0]))
+
+		err := windows.GetAdaptersAddresses(windows.AF_UNSPEC, flags, 0, first, &size)
+		if errors.Is(err, windows.ERROR_BUFFER_OVERFLOW) {
+			continue
+		}
+		if err != nil {
+			return nil, fmt.Errorf("GetAdaptersAddresses: %w", err)
+		}
+
+		for adapter := first; adapter != nil; adapter = adapter.Next {
+			adapters = append(adapters, adapter)
+		}
+		return adapters, nil
+	}
+
+	return nil, fmt.Errorf("GetAdaptersAddresses: buffer kept growing")
+}
+
+func closeKey(k registry.Key) {
+	if err := k.Close(); err != nil {
+		log.Debugf("close registry key: %v", err)
+	}
+}

client/internal/debug/debug_windows_test.go

@@ -0,0 +1,146 @@
+//go:build windows
+
+package debug
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/anonymize"
+)
+
+func newDNSValueGenerator(level anonymize.Level) *BundleGenerator {
+	anonymizer := anonymize.NewAnonymizer(anonymize.DefaultAddresses())
+	anonymizer.SetLevel(level)
+
+	return &BundleGenerator{
+		anonymize:      true,
+		anonymizeLevel: level,
+		anonymizer:     anonymizer,
+	}
+}
+
+// TestAnonymizeValueByName covers the value kinds of the DNS registry keys. The
+// names decide the treatment, because the string pass alone replaces only
+// domains another part of the bundle already seeded.
+func TestAnonymizeValueByName(t *testing.T) {
+	tests := []struct {
+		name      string
+		valueName string
+		value     string
+		assert    func(t *testing.T, got string)
+	}{
+		{
+			name:      "NRPT match domains keep the leading dot",
+			valueName: "Name",
+			value:     ".internal.example.com, .corp.example.org",
+			assert: func(t *testing.T, got string) {
+				t.Helper()
+				for _, entry := range strings.Split(got, ", ") {
+					assert.True(t, strings.HasPrefix(entry, "."), "entry %q should keep its leading dot", entry)
+					assert.NotContains(t, entry, "example", "entry %q should not keep the original domain", entry)
+				}
+			},
+		},
+		{
+			name:      "any value name ending in Domain is treated as a domain",
+			valueName: "ICSDomain",
+			value:     "mshome.net",
+			assert: func(t *testing.T, got string) {
+				t.Helper()
+				assert.NotContains(t, got, "mshome", "should anonymize a domain suffix value")
+			},
+		},
+		{
+			name:      "search list is a comma separated domain list",
+			valueName: "SearchList",
+			value:     "corp.example.com,branch.example.com",
+			assert: func(t *testing.T, got string) {
+				t.Helper()
+				assert.NotContains(t, got, "example", "should anonymize every search domain")
+				assert.Len(t, strings.Split(got, ", "), 2, "should keep both search domains")
+			},
+		},
+		{
+			name:      "name servers are anonymized as addresses",
+			valueName: "DhcpNameServer",
+			value:     "203.0.113.10 8.8.8.8",
+			assert: func(t *testing.T, got string) {
+				t.Helper()
+				assert.NotContains(t, got, "203.0.113.10", "should anonymize a public resolver address")
+				// well-known resolvers stay readable at every level
+				assert.Contains(t, got, "8.8.8.8", "should keep a well-known resolver address")
+			},
+		},
+		{
+			name:      "opaque values are left to the string pass",
+			valueName: "DataBasePath",
+			value:     `%SystemRoot%\System32\drivers\etc`,
+			assert: func(t *testing.T, got string) {
+				t.Helper()
+				assert.Equal(t, `%SystemRoot%\System32\drivers\etc`, got, "should not alter a path")
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			g := newDNSValueGenerator(anonymize.LevelDefault)
+			tc.assert(t, g.anonymizeValue(tc.valueName, tc.value))
+		})
+	}
+}
+
+// TestParseNRPTPolicyTable parses the MOF text of the policy table out
+// parameters, as the provider on a client with one NRPT rule renders it.
+func TestParseNRPTPolicyTable(t *testing.T) {
+	const text = `[abstract]
+class __PARAMETERS
+{
+	[Out, EmbeddedInstance("DnsClientPolicyConfiguration"): ToSubClass, ID(2): DisableOverride ToInstance] DnsClientPolicyConfiguration cmdletOutput[] = {
+instance of DnsClientPolicyConfiguration
+{
+	DirectAccessProxyType = "NoProxy";
+	DirectAccessQueryIPsecRequired = FALSE;
+	NameEncoding = "Utf8WithoutMapping";
+	Namespace = ".0.100.in-addr.arpa";
+}, 
+instance of DnsClientPolicyConfiguration
+{
+	DirectAccessProxyType = "NoProxy";
+	NameEncoding = "Utf8WithoutMapping";
+	NameServers = {"100.0.255.254", "100.0.255.253"};
+	Namespace = ".nb.internal";
+}};
+	[in] boolean Effective;
+	[out] uint32 ReturnValue = 0;
+};
+`
+
+	entries := parseNRPTPolicyTable(text)
+	require.Len(t, entries, 2, "should parse both embedded instances")
+
+	assert.Equal(t, ".0.100.in-addr.arpa", entries[0].namespace, "should read the namespace of the first instance")
+	assert.Equal(t, ".nb.internal", entries[1].namespace, "should read the namespace of the second instance")
+
+	assert.Equal(t, []registryValue{
+		{name: "DirectAccessProxyType", value: "NoProxy"},
+		{name: "DirectAccessQueryIPsecRequired", value: "FALSE"},
+		{name: "NameEncoding", value: "Utf8WithoutMapping"},
+	}, entries[0].values, "should keep the remaining values in order")
+
+	assert.Contains(t, entries[1].values, registryValue{name: "NameServers", value: "100.0.255.254, 100.0.255.253"},
+		"should flatten a MOF array")
+
+	for _, value := range entries[1].values {
+		assert.NotContains(t, value.name, "ReturnValue", "should not read the class level parameters as values")
+	}
+}
+
+func TestParseNRPTPolicyTableEmpty(t *testing.T) {
+	assert.Empty(t, parseNRPTPolicyTable(""), "should parse no entries from empty text")
+	assert.Empty(t, parseNRPTPolicyTable("class __PARAMETERS\n{\n};\n"), "should parse no entries from a table with no instances")
+}

client/internal/debug/nrpt_windows.go

@@ -0,0 +1,317 @@
+//go:build windows
+
+package debug
+
+import (
+	"errors"
+	"fmt"
+	"runtime"
+	"strings"
+	"time"
+
+	"github.com/go-ole/go-ole"
+	"github.com/go-ole/go-ole/oleutil"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	// The NRPT policy table is reachable through the CIM class that backs
+	// Get-DnsClientNrptPolicy. Unlike the rules in the registry, the table is
+	// what the resolver currently has loaded, which is the only way to tell an
+	// applied rule from one that is merely written, in either direction.
+	nrptPolicyNamespace = `root\Microsoft\Windows\DNS`
+	nrptPolicyClass     = "PS_DnsClientNrptPolicy"
+	nrptPolicyMethod    = "Get"
+
+	// The class has no instances, so the table comes from the out parameters
+	// of a static method call, rendered as MOF text: the embedded instances
+	// arrive as a safe array of objects, which cannot be read back through the
+	// COM bindings, and the text form carries all of them.
+	nrptPolicyInstanceKeyword = "instance of DnsClientPolicyConfiguration"
+
+	nrptPolicyTimeout = 15 * time.Second
+)
+
+// COM initialization results that leave the calling thread usable: S_FALSE for
+// a thread this process already initialized, RPC_E_CHANGED_MODE for one that
+// belongs to another apartment.
+const (
+	sFalse          = 0x00000001
+	rpcEChangedMode = 0x80010106
+)
+
+// nrptQueryInFlight admits one read of the policy table at a time. A provider
+// that stops answering keeps its goroutine and the OS thread that goroutine
+// pinned, so a later bundle reports that instead of pinning another one.
+var nrptQueryInFlight = make(chan struct{}, 1)
+
+// nrptPolicyEntry is one namespace of the effective policy table, holding the
+// values of an embedded DnsClientPolicyConfiguration instance in the order the
+// provider reported them.
+type nrptPolicyEntry struct {
+	namespace string
+	values    []registryValue
+}
+
+// registryValue is a name and its rendered value, shared by the registry and
+// policy table readers so both anonymize by value name the same way.
+type registryValue struct {
+	name  string
+	value string
+}
+
+// effectiveNRPTPolicies reads the effective NRPT table. The call is bounded
+// because a WMI provider can block indefinitely and a debug bundle must not.
+func effectiveNRPTPolicies() ([]nrptPolicyEntry, error) {
+	type result struct {
+		text string
+		err  error
+	}
+
+	select {
+	case nrptQueryInFlight <- struct{}{}:
+	default:
+		return nil, errors.New("an earlier read of the policy table has not returned")
+	}
+
+	done := make(chan result, 1)
+	go func() {
+		// the slot is released here rather than by the caller, so a read that
+		// outlives the timeout holds it until the provider answers
+		defer func() { <-nrptQueryInFlight }()
+
+		text, err := nrptPolicyTableText()
+		done <- result{text: text, err: err}
+	}()
+
+	select {
+	case res := <-done:
+		if res.err != nil {
+			return nil, res.err
+		}
+		return parseNRPTPolicyTable(res.text), nil
+	case <-time.After(nrptPolicyTimeout):
+		return nil, errors.New("read of the policy table timed out")
+	}
+}
+
+// nrptPolicyTableText calls the policy table method and returns the MOF text of
+// its out parameters.
+func nrptPolicyTableText() (text string, err error) {
+	// COM is per thread, and the collection is short lived, so the thread is
+	// pinned for the duration rather than initialized for the process.
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	defer func() {
+		// The COM call chain is dynamically typed, so a provider that answers
+		// with an unexpected shape must not take the daemon down with it.
+		if r := recover(); r != nil {
+			err = fmt.Errorf("read NRPT policy table: %v", r)
+		}
+	}()
+
+	owns, err := coInitialize()
+	if err != nil {
+		return "", err
+	}
+	if owns {
+		defer ole.CoUninitialize()
+	}
+
+	locator, err := oleutil.CreateObject("WbemScripting.SWbemLocator")
+	if err != nil {
+		return "", fmt.Errorf("create WMI locator: %w", err)
+	}
+	defer locator.Release()
+
+	dispatch, err := locator.QueryInterface(ole.IID_IDispatch)
+	if err != nil {
+		return "", fmt.Errorf("query WMI locator interface: %w", err)
+	}
+	defer dispatch.Release()
+
+	service, err := dispatchCall(dispatch, "ConnectServer", nil, nrptPolicyNamespace)
+	if err != nil {
+		return "", fmt.Errorf("connect to %s: %w", nrptPolicyNamespace, err)
+	}
+	defer service.Release()
+
+	inParams, err := spawnMethodInParams(service)
+	if err != nil {
+		return "", err
+	}
+	defer inParams.Release()
+
+	// The effective table is the merge of the local and the group policy
+	// store, which is what the resolver answers from.
+	if _, err := oleutil.PutProperty(inParams, "Effective", true); err != nil {
+		return "", fmt.Errorf("set Effective parameter: %w", err)
+	}
+
+	outParams, err := dispatchCall(service, "ExecMethod", nrptPolicyClass, nrptPolicyMethod, inParams)
+	if err != nil {
+		return "", fmt.Errorf("call %s.%s: %w", nrptPolicyClass, nrptPolicyMethod, err)
+	}
+	defer outParams.Release()
+
+	textVariant, err := oleutil.CallMethod(outParams, "GetObjectText_")
+	if err != nil {
+		return "", fmt.Errorf("render policy table: %w", err)
+	}
+	defer func() {
+		if err := textVariant.Clear(); err != nil {
+			log.Debugf("clear policy table variant: %v", err)
+		}
+	}()
+
+	return textVariant.ToString(), nil
+}
+
+// spawnMethodInParams builds the in parameters instance the method needs. The
+// provider rejects the call without one, even when every parameter is optional.
+func spawnMethodInParams(service *ole.IDispatch) (*ole.IDispatch, error) {
+	class, err := dispatchCall(service, "Get", nrptPolicyClass)
+	if err != nil {
+		return nil, fmt.Errorf("get class %s: %w", nrptPolicyClass, err)
+	}
+	defer class.Release()
+
+	methods, err := dispatchProperty(class, "Methods_")
+	if err != nil {
+		return nil, fmt.Errorf("get class methods: %w", err)
+	}
+	defer methods.Release()
+
+	method, err := dispatchCall(methods, "Item", nrptPolicyMethod)
+	if err != nil {
+		return nil, fmt.Errorf("get method %s: %w", nrptPolicyMethod, err)
+	}
+	defer method.Release()
+
+	params, err := dispatchProperty(method, "InParameters")
+	if err != nil {
+		return nil, fmt.Errorf("get method parameters: %w", err)
+	}
+	defer params.Release()
+
+	inParams, err := dispatchCall(params, "SpawnInstance_")
+	if err != nil {
+		return nil, fmt.Errorf("spawn parameter instance: %w", err)
+	}
+
+	return inParams, nil
+}
+
+// parseNRPTPolicyTable pulls the embedded instances out of the MOF text. Each
+// instance is a namespace of the table, with one name and value per line.
+func parseNRPTPolicyTable(text string) []nrptPolicyEntry {
+	var entries []nrptPolicyEntry
+	var current *nrptPolicyEntry
+
+	for _, line := range strings.Split(text, "\n") {
+		line = strings.TrimSpace(strings.TrimSuffix(strings.TrimSpace(line), ";"))
+
+		switch {
+		case strings.HasPrefix(line, nrptPolicyInstanceKeyword):
+			entries = append(entries, nrptPolicyEntry{})
+			current = &entries[len(entries)-1]
+			continue
+		case strings.HasPrefix(line, "}"):
+			// closes an instance, and the array with the last one, so the
+			// class level parameters that follow are not read as values
+			current = nil
+			continue
+		case current == nil, line == "{":
+			continue
+		}
+
+		name, value, ok := strings.Cut(line, " = ")
+		if !ok {
+			continue
+		}
+
+		value = unquoteMOFValue(value)
+		if name == "Namespace" {
+			current.namespace = value
+			continue
+		}
+
+		current.values = append(current.values, registryValue{name: name, value: value})
+	}
+
+	return entries
+}
+
+// unquoteMOFValue renders a MOF scalar or array as plain text: "a" becomes a,
+// and {"a", "b"} becomes a, b.
+func unquoteMOFValue(value string) string {
+	value = strings.TrimSpace(value)
+
+	if inner, ok := strings.CutPrefix(value, "{"); ok {
+		value = strings.TrimSuffix(inner, "}")
+
+		entries := strings.Split(value, ",")
+		for i, entry := range entries {
+			entries[i] = strings.Trim(strings.TrimSpace(entry), `"`)
+		}
+		return strings.Join(entries, ", ")
+	}
+
+	return strings.Trim(value, `"`)
+}
+
+// coInitialize prepares the calling thread for COM and reports whether this
+// call owns the initialization, which decides whether it may be balanced with
+// CoUninitialize. S_FALSE took a reference on a thread this process had already
+// initialized and so has to be released, while RPC_E_CHANGED_MODE took none:
+// the thread belongs to another apartment, which is usable but is not ours to
+// uninitialize.
+func coInitialize() (bool, error) {
+	err := ole.CoInitializeEx(0, ole.COINIT_MULTITHREADED)
+	if err == nil {
+		return true, nil
+	}
+
+	var oleErr *ole.OleError
+	if errors.As(err, &oleErr) {
+		switch oleErr.Code() {
+		case sFalse:
+			return true, nil
+		case rpcEChangedMode:
+			return false, nil
+		}
+	}
+
+	return false, fmt.Errorf("initialize COM: %w", err)
+}
+
+// dispatchCall calls a COM method that returns an object.
+func dispatchCall(dispatch *ole.IDispatch, method string, params ...any) (*ole.IDispatch, error) {
+	variant, err := oleutil.CallMethod(dispatch, method, params...)
+	if err != nil {
+		return nil, err
+	}
+
+	object := variant.ToIDispatch()
+	if object == nil {
+		return nil, fmt.Errorf("%s returned no object", method)
+	}
+
+	return object, nil
+}
+
+// dispatchProperty reads a COM property that holds an object.
+func dispatchProperty(dispatch *ole.IDispatch, property string) (*ole.IDispatch, error) {
+	variant, err := oleutil.GetProperty(dispatch, property)
+	if err != nil {
+		return nil, err
+	}
+
+	object := variant.ToIDispatch()
+	if object == nil {
+		return nil, fmt.Errorf("property %s holds no object", property)
+	}
+
+	return object, nil
+}

client/internal/debug/uilog_test.go

@@ -0,0 +1,64 @@
+package debug
+
+import (
+	"archive/zip"
+	"bytes"
+	"fmt"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/configs"
+)
+
+// bundleEntries generates a bundle with the given generator and returns the
+// set of entry names in the resulting archive.
+func bundleEntries(t *testing.T, g *BundleGenerator) map[string]struct{} {
+	t.Helper()
+
+	path, err := g.Generate()
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = os.Remove(path) })
+
+	data, err := os.ReadFile(path)
+	require.NoError(t, err)
+
+	zr, err := zip.NewReader(bytes.NewReader(data), int64(len(data)))
+	require.NoError(t, err)
+
+	names := make(map[string]struct{}, len(zr.File))
+	for _, f := range zr.File {
+		names[f.Name] = struct{}{}
+	}
+	return names
+}
+
+func TestBundleIncludesUILogWhenOpenerAllows(t *testing.T) {
+	path := filepath.Join(t.TempDir(), configs.UILogFile)
+	require.NoError(t, os.WriteFile(path, []byte("gui log"), 0600))
+
+	g := NewBundleGenerator(GeneratorDependencies{
+		UILogPath:   path,
+		UILogOpener: openLogFile,
+	}, BundleConfig{})
+
+	require.Contains(t, bundleEntries(t, g), configs.UILogFile)
+}
+
+// A UILogOpener that refuses (as the ownership check does for a foreign file)
+// keeps the UI log out of the bundle without failing bundle generation.
+func TestBundleExcludesUILogWhenOpenerRefuses(t *testing.T) {
+	path := filepath.Join(t.TempDir(), configs.UILogFile)
+	require.NoError(t, os.WriteFile(path, []byte("secret"), 0600))
+
+	g := NewBundleGenerator(GeneratorDependencies{
+		UILogPath: path,
+		UILogOpener: func(string) (*os.File, error) {
+			return nil, fmt.Errorf("not owned by the caller")
+		},
+	}, BundleConfig{})
+
+	require.NotContains(t, bundleEntries(t, g), configs.UILogFile)
+}

client/internal/debug/upload.go

@@ -3,10 +3,12 @@ package debug
 import (
 	"context"
 	"crypto/sha256"
+	"crypto/tls"
 	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
+	neturl "net/url"
 	"os"
 
 	"github.com/netbirdio/netbird/upload-server/types"
@@ -14,20 +16,80 @@ import (
 
 const maxBundleUploadSize = 50 * 1024 * 1024
 
-func UploadDebugBundle(ctx context.Context, url, managementURL, filePath string) (key string, err error) {
-	response, err := getUploadURL(ctx, url, managementURL)
+// requireHTTPS refuses any URL the daemon would fetch or upload to that is not
+// https. The daemon runs as root and the bundle carries its logs and state, so a
+// plaintext hop is a place to intercept the bundle or the presigned redirect.
+// The server-side gate already enforces this for the desktop path; this also
+// covers the mobile and job-runner callers that reach this package directly.
+// Skipped when the caller opted into an insecure upload (self-hosted server).
+func requireHTTPS(what, rawURL string) error {
+	parsed, err := neturl.Parse(rawURL)
+	if err != nil {
+		return fmt.Errorf("parse %s: %w", what, err)
+	}
+	if parsed.Scheme != "https" {
+		return fmt.Errorf("%s must use https, got scheme %q", what, parsed.Scheme)
+	}
+	return nil
+}
+
+// uploadClient returns the HTTP client for the upload requests. The default
+// client verifies TLS and refuses a redirect that would downgrade to a non-https
+// hop, so a bundle can never leave over http after an https start. The insecure
+// variant accepts http and untrusted certificates, and is only reachable for a
+// privileged caller that passed --upload-bundle-insecure (see
+// requirePrivilegeForUploadURL).
+func uploadClient(insecure bool) *http.Client {
+	if !insecure {
+		return &http.Client{CheckRedirect: rejectInsecureRedirect}
+	}
+	return &http.Client{
+		Transport: &http.Transport{
+			//nolint:gosec // opt-in, privileged, self-hosted upload servers
+			TLSClientConfig: &tls.Config{InsecureSkipVerify: true, MinVersion: tls.VersionTLS12},
+		},
+	}
+}
+
+// rejectInsecureRedirect refuses a redirect to a non-https target and keeps the
+// standard library's 10-hop limit that a custom CheckRedirect would otherwise
+// disable.
+func rejectInsecureRedirect(req *http.Request, via []*http.Request) error {
+	if req.URL.Scheme != "https" {
+		return fmt.Errorf("refusing redirect to non-https URL %s", req.URL.Redacted())
+	}
+	if len(via) >= 10 {
+		return fmt.Errorf("stopped after 10 redirects")
+	}
+	return nil
+}
+
+func UploadDebugBundle(ctx context.Context, url, managementURL, filePath string, insecure bool) (key string, err error) {
+	if !insecure {
+		if err := requireHTTPS("upload service URL", url); err != nil {
+			return "", err
+		}
+	}
+
+	response, err := getUploadURL(ctx, url, managementURL, insecure)
 	if err != nil {
 		return "", err
 	}
 
-	err = upload(ctx, filePath, response)
+	if !insecure {
+		if err := requireHTTPS("upload URL from service", response.URL); err != nil {
+			return "", err
+		}
+	}
+
+	err = upload(ctx, filePath, response, insecure)
 	if err != nil {
 		return "", err
 	}
 	return response.Key, nil
 }
 
-func upload(ctx context.Context, filePath string, response *types.GetURLResponse) error {
+func upload(ctx context.Context, filePath string, response *types.GetURLResponse, insecure bool) error {
 	fileData, err := os.Open(filePath)
 	if err != nil {
 		return fmt.Errorf("open file: %w", err)
@@ -52,7 +114,7 @@ func upload(ctx context.Context, filePath string, response *types.GetURLResponse
 	req.ContentLength = stat.Size()
 	req.Header.Set("Content-Type", "application/octet-stream")
 
-	putResp, err := http.DefaultClient.Do(req)
+	putResp, err := uploadClient(insecure).Do(req)
 	if err != nil {
 		return fmt.Errorf("upload failed: %v", err)
 	}
@@ -65,16 +127,23 @@ func upload(ctx context.Context, filePath string, response *types.GetURLResponse
 	return nil
 }
 
-func getUploadURL(ctx context.Context, url string, managementURL string) (*types.GetURLResponse, error) {
-	id := getURLHash(managementURL)
-	getReq, err := http.NewRequestWithContext(ctx, "GET", url+"?id="+id, nil)
+func getUploadURL(ctx context.Context, serviceURL string, managementURL string, insecure bool) (*types.GetURLResponse, error) {
+	parsed, err := neturl.Parse(serviceURL)
+	if err != nil {
+		return nil, fmt.Errorf("parse upload service URL: %w", err)
+	}
+	q := parsed.Query()
+	q.Set("id", getURLHash(managementURL))
+	parsed.RawQuery = q.Encode()
+
+	getReq, err := http.NewRequestWithContext(ctx, "GET", parsed.String(), nil)
 	if err != nil {
 		return nil, fmt.Errorf("create GET request: %w", err)
 	}
 
 	getReq.Header.Set(types.ClientHeader, types.ClientHeaderValue)
 
-	resp, err := http.DefaultClient.Do(getReq)
+	resp, err := uploadClient(insecure).Do(getReq)
 	if err != nil {
 		return nil, fmt.Errorf("get presigned URL: %w", err)
 	}

client/internal/debug/upload_test.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"net"
 	"net/http"
+	"net/http/httptest"
 	"os"
 	"path/filepath"
 	"testing"
@@ -43,7 +44,7 @@ func TestUpload(t *testing.T) {
 	fileContent := []byte("test file content")
 	err := os.WriteFile(file, fileContent, 0640)
 	require.NoError(t, err)
-	key, err := UploadDebugBundle(context.Background(), testURL+types.GetURLPath, testURL, file)
+	key, err := UploadDebugBundle(context.Background(), testURL+types.GetURLPath, testURL, file, true)
 	require.NoError(t, err)
 	id := getURLHash(testURL)
 	require.Contains(t, key, id+"/")
@@ -79,3 +80,47 @@ func waitForServer(t *testing.T, addr string) {
 	}
 	t.Fatalf("server did not start listening on %s in time", addr)
 }
+
+func TestRequireHTTPS(t *testing.T) {
+	require.NoError(t, requireHTTPS("upload URL", "https://upload.example/path"))
+	require.Error(t, requireHTTPS("upload URL", "http://upload.example/path"))
+	require.Error(t, requireHTTPS("upload URL", "ftp://upload.example/path"))
+	require.Error(t, requireHTTPS("upload URL", "://malformed"))
+}
+
+func TestRejectInsecureRedirect(t *testing.T) {
+	httpsReq, err := http.NewRequest(http.MethodGet, "https://a.example/", nil)
+	require.NoError(t, err)
+	require.NoError(t, rejectInsecureRedirect(httpsReq, nil), "https redirect target must be allowed")
+
+	httpReq, err := http.NewRequest(http.MethodGet, "http://a.example/", nil)
+	require.NoError(t, err)
+	require.Error(t, rejectInsecureRedirect(httpReq, nil), "http redirect target must be refused")
+
+	require.Error(t, rejectInsecureRedirect(httpsReq, make([]*http.Request, 10)), "the 10-redirect limit must be enforced")
+}
+
+// The secure client refuses to follow an https response that redirects to http,
+// so a bundle can't be downgraded onto plaintext mid-flight.
+func TestUploadClientRefusesHTTPSToHTTPRedirect(t *testing.T) {
+	plain := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+	t.Cleanup(plain.Close)
+
+	secure := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Redirect(w, r, plain.URL, http.StatusFound)
+	}))
+	t.Cleanup(secure.Close)
+
+	client := uploadClient(false)
+	// Trust the test server's cert without disabling verification globally.
+	client.Transport = secure.Client().Transport
+
+	resp, err := client.Get(secure.URL)
+	if resp != nil {
+		_ = resp.Body.Close()
+	}
+	require.Error(t, err, "redirect from https to http must be refused")
+	require.Contains(t, err.Error(), "non-https")
+}

client/internal/debug/wgshow.go

@@ -35,14 +35,14 @@ func (g *BundleGenerator) toWGShowFormat(s *configurer.Stats) string {
 	var sb strings.Builder
 
 	sb.WriteString(fmt.Sprintf("interface: %s\n", s.DeviceName))
-	sb.WriteString(fmt.Sprintf("  public key: %s\n", s.PublicKey))
+	sb.WriteString(fmt.Sprintf("  public key: %s\n", g.anonymizer.AnonymizeWGKey(s.PublicKey)))
 	sb.WriteString(fmt.Sprintf("  listen port: %d\n", s.ListenPort))
 	if s.FWMark != 0 {
 		sb.WriteString(fmt.Sprintf("  fwmark: %#x\n", s.FWMark))
 	}
 
 	for _, peer := range s.Peers {
-		sb.WriteString(fmt.Sprintf("\npeer: %s\n", peer.PublicKey))
+		sb.WriteString(fmt.Sprintf("\npeer: %s\n", g.anonymizer.AnonymizeWGKey(peer.PublicKey)))
 		if peer.Endpoint.IP != nil {
 			if g.anonymize {
 				anonEndpoint := g.anonymizer.AnonymizeUDPAddr(peer.Endpoint)
@@ -54,7 +54,11 @@ func (g *BundleGenerator) toWGShowFormat(s *configurer.Stats) string {
 		if len(peer.AllowedIPs) > 0 {
 			var ipStrings []string
 			for _, ipnet := range peer.AllowedIPs {
-				ipStrings = append(ipStrings, ipnet.String())
+				ipStr := ipnet.String()
+				if g.anonymize {
+					ipStr = g.anonymizer.AnonymizeIPString(ipStr)
+				}
+				ipStrings = append(ipStrings, ipStr)
 			}
 			sb.WriteString(fmt.Sprintf("  allowed ips: %s\n", strings.Join(ipStrings, ", ")))
 		}

client/internal/dns/host_darwin.go

@@ -267,18 +267,38 @@ func (s *systemConfigurator) getSystemDNSSettings() (SystemDNSSettings, error) {
 		return SystemDNSSettings{}, fmt.Errorf("sending the command: %w", err)
 	}
 
-	var dnsSettings SystemDNSSettings
+	dnsSettings, serverAddresses, err := parseSystemDNSSettings(b)
+	if err != nil {
+		return dnsSettings, err
+	}
+
+	s.mu.Lock()
+	s.origNameservers = serverAddresses
+	s.mu.Unlock()
+
+	return dnsSettings, nil
+}
+
+// parseSystemDNSSettings parses the output of `scutil show State:/Network/Service/<id>/DNS`.
+// Lines that don't match the expected "index : value" shape are skipped: hosts with unusual
+// network services (e.g. orphaned hardware ports) can produce entries without a value.
+func parseSystemDNSSettings(out []byte) (SystemDNSSettings, []netip.Addr, error) {
+	// port is not exposed by scutil, default to 53
+	dnsSettings := SystemDNSSettings{ServerPort: DefaultPort}
 	var serverAddresses []netip.Addr
 	inSearchDomainsArray := false
 	inServerAddressesArray := false
 
-	scanner := bufio.NewScanner(bytes.NewReader(b))
+	scanner := bufio.NewScanner(bytes.NewReader(out))
 	for scanner.Scan() {
 		line := strings.TrimSpace(scanner.Text())
 		switch {
 		case strings.HasPrefix(line, "DomainName :"):
-			domainName := strings.TrimSpace(strings.Split(line, ":")[1])
-			dnsSettings.Domains = append(dnsSettings.Domains, domainName)
+			domainName := strings.TrimSpace(strings.TrimPrefix(line, "DomainName :"))
+			if domainName != "" {
+				dnsSettings.Domains = append(dnsSettings.Domains, domainName)
+			}
+			continue
 		case line == "SearchDomains : <array> {":
 			inSearchDomainsArray = true
 			continue
@@ -288,36 +308,45 @@ func (s *systemConfigurator) getSystemDNSSettings() (SystemDNSSettings, error) {
 		case line == "}":
 			inSearchDomainsArray = false
 			inServerAddressesArray = false
+			continue
+		}
+
+		if !inSearchDomainsArray && !inServerAddressesArray {
+			continue
+		}
+
+		parts := strings.SplitN(line, " : ", 2)
+		if len(parts) != 2 {
+			log.Debugf("skipping unexpected scutil DNS line %q", line)
+			continue
+		}
+		value := strings.TrimSpace(parts[1])
+		if value == "" {
+			continue
 		}
 
 		if inSearchDomainsArray {
-			searchDomain := strings.Split(line, " : ")[1]
-			dnsSettings.Domains = append(dnsSettings.Domains, searchDomain)
-		} else if inServerAddressesArray {
-			address := strings.Split(line, " : ")[1]
-			if ip, err := netip.ParseAddr(address); err == nil && !ip.IsUnspecified() {
-				ip = ip.Unmap()
-				serverAddresses = append(serverAddresses, ip)
-				// Prefer the first IPv4 server as ServerIP since our DNS listener is IPv4.
-				if !dnsSettings.ServerIP.IsValid() && ip.Is4() {
-					dnsSettings.ServerIP = ip
-				}
-			}
+			dnsSettings.Domains = append(dnsSettings.Domains, value)
+			continue
+		}
+
+		ip, err := netip.ParseAddr(value)
+		if err != nil || ip.IsUnspecified() {
+			continue
+		}
+		ip = ip.Unmap()
+		serverAddresses = append(serverAddresses, ip)
+		// Prefer the first IPv4 server as ServerIP since our DNS listener is IPv4.
+		if !dnsSettings.ServerIP.IsValid() && ip.Is4() {
+			dnsSettings.ServerIP = ip
 		}
 	}
 
 	if err := scanner.Err(); err != nil {
-		return dnsSettings, err
+		return dnsSettings, serverAddresses, err
 	}
 
-	// default to 53 port
-	dnsSettings.ServerPort = DefaultPort
-
-	s.mu.Lock()
-	s.origNameservers = serverAddresses
-	s.mu.Unlock()
-
-	return dnsSettings, nil
+	return dnsSettings, serverAddresses, nil
 }
 
 func (s *systemConfigurator) getOriginalNameservers() []netip.Addr {
@@ -435,11 +464,15 @@ func (s *systemConfigurator) getPrimaryService() (string, string, error) {
 	router := ""
 	for scanner.Scan() {
 		text := scanner.Text()
+		parts := strings.SplitN(text, ":", 2)
+		if len(parts) != 2 {
+			continue
+		}
 		if strings.Contains(text, "PrimaryService") {
-			primaryService = strings.TrimSpace(strings.Split(text, ":")[1])
+			primaryService = strings.TrimSpace(parts[1])
 		}
 		if strings.Contains(text, "Router") {
-			router = strings.TrimSpace(strings.Split(text, ":")[1])
+			router = strings.TrimSpace(parts[1])
 		}
 	}
 	if err := scanner.Err(); err != nil && err != io.EOF {

client/internal/dns/host_darwin_test.go

@@ -328,6 +328,120 @@ func removeTestDNSKey(key string) error {
 	return err
 }
 
+func TestParseSystemDNSSettings(t *testing.T) {
+	tests := []struct {
+		name            string
+		output          string
+		expectedDomains []string
+		expectedServers []netip.Addr
+		expectedIP      netip.Addr
+	}{
+		{
+			name: "well_formed",
+			output: `<dictionary> {
+  DomainName : example.com
+  SearchDomains : <array> {
+    0 : example.com
+    1 : corp.example.com
+  }
+  ServerAddresses : <array> {
+    0 : 192.168.1.1
+    1 : fd00::53
+  }
+}
+`,
+			expectedDomains: []string{"example.com", "example.com", "corp.example.com"},
+			expectedServers: []netip.Addr{netip.MustParseAddr("192.168.1.1"), netip.MustParseAddr("fd00::53")},
+			expectedIP:      netip.MustParseAddr("192.168.1.1"),
+		},
+		{
+			// entries without a value after the separator used to panic with
+			// "index out of range [1] with length 1"
+			name: "malformed_array_entries_skipped",
+			output: `<dictionary> {
+  SearchDomains : <array> {
+    0 :
+    (null)
+
+    1 : corp.example.com
+  }
+  ServerAddresses : <array> {
+    0 :
+    1 : 192.168.1.1
+  }
+}
+`,
+			expectedDomains: []string{"corp.example.com"},
+			expectedServers: []netip.Addr{netip.MustParseAddr("192.168.1.1")},
+			expectedIP:      netip.MustParseAddr("192.168.1.1"),
+		},
+		{
+			name: "domain_name_without_value_skipped",
+			output: `<dictionary> {
+  DomainName :
+  ServerAddresses : <array> {
+    0 : 192.168.1.1
+  }
+}
+`,
+			expectedServers: []netip.Addr{netip.MustParseAddr("192.168.1.1")},
+			expectedIP:      netip.MustParseAddr("192.168.1.1"),
+		},
+		{
+			name: "ipv6_first_prefers_ipv4_server_ip",
+			output: `<dictionary> {
+  ServerAddresses : <array> {
+    0 : fd00::53
+    1 : 192.168.1.1
+  }
+}
+`,
+			expectedServers: []netip.Addr{netip.MustParseAddr("fd00::53"), netip.MustParseAddr("192.168.1.1")},
+			expectedIP:      netip.MustParseAddr("192.168.1.1"),
+		},
+		{
+			name: "invalid_and_unspecified_addresses_skipped",
+			output: `<dictionary> {
+  ServerAddresses : <array> {
+    0 : (null)
+    1 : 0.0.0.0
+    2 : 192.168.1.1
+  }
+}
+`,
+			expectedServers: []netip.Addr{netip.MustParseAddr("192.168.1.1")},
+			expectedIP:      netip.MustParseAddr("192.168.1.1"),
+		},
+		{
+			name: "v4_mapped_address_unmapped",
+			output: `<dictionary> {
+  ServerAddresses : <array> {
+    0 : ::ffff:192.168.1.1
+  }
+}
+`,
+			expectedServers: []netip.Addr{netip.MustParseAddr("192.168.1.1")},
+			expectedIP:      netip.MustParseAddr("192.168.1.1"),
+		},
+		{
+			name:   "empty_output",
+			output: "",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			settings, servers, err := parseSystemDNSSettings([]byte(tc.output))
+			require.NoError(t, err, "parsing should not fail")
+
+			assert.Equal(t, tc.expectedDomains, settings.Domains, "domains should match")
+			assert.Equal(t, tc.expectedServers, servers, "server addresses should match")
+			assert.Equal(t, tc.expectedIP, settings.ServerIP, "server IP should match")
+			assert.Equal(t, DefaultPort, settings.ServerPort, "server port should default to 53")
+		})
+	}
+}
+
 func TestGetOriginalNameservers(t *testing.T) {
 	configurator := &systemConfigurator{
 		createdKeys: make(map[string]struct{}),

client/internal/dns/host_windows.go

@@ -32,10 +32,30 @@ var (
 	dnsFlushResolverCacheFn = dnsapi.NewProc("DnsFlushResolverCache")
 )
 
+// Registry locations of the host DNS configuration this package programs,
+// exported so a diagnostic reader reports the same locations that are written.
 const (
-	dnsPolicyConfigMatchPath    = `SYSTEM\CurrentControlSet\Services\Dnscache\Parameters\DnsPolicyConfig\NetBird-Match`
-	gpoDnsPolicyRoot            = `SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\DnsPolicyConfig`
-	gpoDnsPolicyConfigMatchPath = gpoDnsPolicyRoot + `\NetBird-Match`
+	// NRPTKeyPrefix starts the name of every NRPT rule key this client creates.
+	// Older versions used different layouts under the same prefix: a single
+	// unsuffixed key, then one key per domain, now one key per batch of domains.
+	NRPTKeyPrefix = "NetBird-Match"
+
+	// DNSPolicyConfigRoot holds the NRPT rules of the local policy store.
+	DNSPolicyConfigRoot = `SYSTEM\CurrentControlSet\Services\Dnscache\Parameters\DnsPolicyConfig`
+
+	// GPODNSPolicyConfigRoot holds the NRPT rules of the group policy store,
+	// which takes precedence over the local one when it is present.
+	GPODNSPolicyConfigRoot = `SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\DnsPolicyConfig`
+
+	// InterfaceConfigPath and InterfaceConfigPathV6 hold the per-interface DNS
+	// settings, keyed by interface GUID, in separate hives per address family.
+	InterfaceConfigPath   = `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces`
+	InterfaceConfigPathV6 = `SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters\Interfaces`
+)
+
+const (
+	dnsPolicyConfigMatchPath    = DNSPolicyConfigRoot + `\` + NRPTKeyPrefix
+	gpoDnsPolicyConfigMatchPath = GPODNSPolicyConfigRoot + `\` + NRPTKeyPrefix
 
 	dnsPolicyConfigVersionKey           = "Version"
 	dnsPolicyConfigVersionValue         = 2
@@ -46,8 +66,6 @@ const (
 
 	nrptMaxDomainsPerRule = 50
 
-	interfaceConfigPath           = `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces`
-	interfaceConfigPathV6         = `SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters\Interfaces`
 	interfaceConfigNameServerKey  = "NameServer"
 	interfaceConfigDhcpNameSrvKey = "DhcpNameServer"
 	interfaceConfigSearchListKey  = "SearchList"
@@ -86,7 +104,7 @@ func newHostManager(wgInterface WGIface) (*registryConfigurator, error) {
 	}
 
 	var useGPO bool
-	k, err := registry.OpenKey(registry.LOCAL_MACHINE, gpoDnsPolicyRoot, registry.QUERY_VALUE)
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, GPODNSPolicyConfigRoot, registry.QUERY_VALUE)
 	if err != nil {
 		log.Debugf("failed to open GPO DNS policy root: %v", err)
 	} else {
@@ -126,7 +144,7 @@ func (r *registryConfigurator) captureOriginalNameservers() ([]netip.Addr, error
 	seen := make(map[netip.Addr]struct{})
 	var out []netip.Addr
 	var merr *multierror.Error
-	for _, root := range []string{interfaceConfigPath, interfaceConfigPathV6} {
+	for _, root := range []string{InterfaceConfigPath, InterfaceConfigPathV6} {
 		addrs, err := r.captureFromTcpipRoot(root)
 		if err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("%s: %w", root, err))
@@ -301,14 +319,9 @@ func (r *registryConfigurator) applyDNSConfig(config HostDNSConfig, stateManager
 	}
 
 	if len(matchDomains) != 0 {
-		count, err := r.addDNSMatchPolicy(matchDomains, config.ServerIP)
-		// Update count even on error to ensure cleanup covers partially created rules
-		r.nrptEntryCount = count
-		if err != nil {
+		if err := r.addDNSMatchPolicy(matchDomains, config.ServerIP); err != nil {
 			return fmt.Errorf("add dns match policy: %w", err)
 		}
-	} else {
-		r.nrptEntryCount = 0
 	}
 
 	r.updateState(stateManager)
@@ -353,9 +366,8 @@ func (r *registryConfigurator) applyRouteAll(config HostDNSConfig) error {
 
 func (r *registryConfigurator) updateState(stateManager *statemanager.Manager) {
 	if err := stateManager.UpdateState(&ShutdownState{
-		Guid:           r.guid,
-		GPO:            r.gpo,
-		NRPTEntryCount: r.nrptEntryCount,
+		Guid: r.guid,
+		GPO:  r.gpo,
 	}); err != nil {
 		log.Errorf("failed to update shutdown state: %s", err)
 	}
@@ -370,7 +382,7 @@ func (r *registryConfigurator) addDNSSetupForAll(ip netip.Addr) error {
 	return nil
 }
 
-func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr) (int, error) {
+func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr) error {
 	// if the gpo key is present, we need to put our DNS settings there, otherwise our config might be ignored
 	// see https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-gpnrpt/8cc31cb9-20cb-4140-9e85-3e08703b4745
 
@@ -387,19 +399,17 @@ func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr
 		gpoPath := fmt.Sprintf("%s-%d", gpoDnsPolicyConfigMatchPath, ruleIndex)
 
 		if err := r.configureDNSPolicy(localPath, batchDomains, ip); err != nil {
-			return ruleIndex, fmt.Errorf("configure DNS Local policy for rule %d: %w", ruleIndex, err)
+			return fmt.Errorf("configure DNS Local policy for rule %d: %w", ruleIndex, err)
 		}
 
-		// Increment immediately so the caller's cleanup path knows about this rule
-		ruleIndex++
-
 		if r.gpo {
 			if err := r.configureDNSPolicy(gpoPath, batchDomains, ip); err != nil {
-				return ruleIndex, fmt.Errorf("configure gpo DNS policy for rule %d: %w", ruleIndex-1, err)
+				return fmt.Errorf("configure gpo DNS policy for rule %d: %w", ruleIndex, err)
 			}
 		}
 
-		log.Debugf("added NRPT rule %d with %d domains", ruleIndex-1, len(batchDomains))
+		log.Debugf("added NRPT rule %d with %d domains", ruleIndex, len(batchDomains))
+		ruleIndex++
 	}
 
 	if r.gpo {
@@ -409,7 +419,7 @@ func (r *registryConfigurator) addDNSMatchPolicy(domains []string, ip netip.Addr
 	}
 
 	log.Infof("added %d NRPT rules for %d domains", ruleIndex, len(domains))
-	return ruleIndex, nil
+	return nil
 }
 
 func (r *registryConfigurator) configureDNSPolicy(policyPath string, domains []string, ip netip.Addr) error {
@@ -474,7 +484,7 @@ func (r *registryConfigurator) flushDNSCache() {
 
 	ret, _, err := dnsFlushResolverCacheFn.Call()
 	if ret == 0 {
-		if err != nil && !errors.Is(err, syscall.Errno(0)) {
+		if !errors.Is(err, syscall.Errno(0)) {
 			log.Errorf("DnsFlushResolverCache failed: %v", err)
 			return
 		}
@@ -520,7 +530,7 @@ func (r *registryConfigurator) deleteInterfaceRegistryKeyProperty(propertyKey st
 }
 
 func (r *registryConfigurator) getInterfaceRegistryKey() (registry.Key, error) {
-	regKeyPath := interfaceConfigPath + "\\" + r.guid
+	regKeyPath := InterfaceConfigPath + "\\" + r.guid
 	regKey, err := registry.OpenKey(registry.LOCAL_MACHINE, regKeyPath, registry.SET_VALUE)
 	if err != nil {
 		return regKey, fmt.Errorf("open HKEY_LOCAL_MACHINE\\%s: %w", regKeyPath, err)
@@ -546,28 +556,28 @@ func (r *registryConfigurator) restoreHostDNS() error {
 	return nil
 }
 
+// removeDNSMatchPolicies deletes every NRPT rule this client may have created,
+// from the local and the GPO policy store. The rules are found by enumerating
+// the registry, the only authoritative record of what was written. Cleanup must
+// not depend on a rule count: the in-memory one is scoped to a single
+// registryConfigurator and the persisted one is deleted on every clean
+// disconnect, and a rule left behind keeps resolving names over an interface
+// that is gone, until reboot discards the volatile key.
 func (r *registryConfigurator) removeDNSMatchPolicies() error {
 	var merr *multierror.Error
 
-	// Try to remove the base entries (for backward compatibility)
-	if err := removeRegistryKeyFromDNSPolicyConfig(dnsPolicyConfigMatchPath); err != nil {
-		merr = multierror.Append(merr, fmt.Errorf("remove local base entry: %w", err))
-	}
-
-	if err := removeRegistryKeyFromDNSPolicyConfig(gpoDnsPolicyConfigMatchPath); err != nil {
-		merr = multierror.Append(merr, fmt.Errorf("remove GPO base entry: %w", err))
-	}
-
-	for i := 0; i < r.nrptEntryCount; i++ {
-		localPath := fmt.Sprintf("%s-%d", dnsPolicyConfigMatchPath, i)
-		gpoPath := fmt.Sprintf("%s-%d", gpoDnsPolicyConfigMatchPath, i)
-
-		if err := removeRegistryKeyFromDNSPolicyConfig(localPath); err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("remove local entry %d: %w", i, err))
+	for _, root := range []string{DNSPolicyConfigRoot, GPODNSPolicyConfigRoot} {
+		names, err := listNRPTRuleKeys(root)
+		if err != nil {
+			merr = multierror.Append(merr, fmt.Errorf("list rule keys under %s: %w", root, err))
+			continue
 		}
 
-		if err := removeRegistryKeyFromDNSPolicyConfig(gpoPath); err != nil {
-			merr = multierror.Append(merr, fmt.Errorf("remove GPO entry %d: %w", i, err))
+		for _, name := range names {
+			path := root + `\` + name
+			if err := removeRegistryKeyFromDNSPolicyConfig(path); err != nil {
+				merr = multierror.Append(merr, fmt.Errorf("remove entry %s: %w", path, err))
+			}
 		}
 	}
 
@@ -582,6 +592,39 @@ func (r *registryConfigurator) restoreUncleanShutdownDNS() error {
 	return r.restoreHostDNS()
 }
 
+// listNRPTRuleKeys returns the names of our NRPT rule keys under a policy store
+// root. An absent root holds nothing to clean up, which is the normal state of
+// the GPO store on a machine without DNS Client policy.
+func listNRPTRuleKeys(root string) ([]string, error) {
+	k, err := registry.OpenKey(registry.LOCAL_MACHINE, root, registry.ENUMERATE_SUB_KEYS)
+	switch {
+	case errors.Is(err, registry.ErrNotExist), errors.Is(err, syscall.ERROR_PATH_NOT_FOUND):
+		// the GPO store is absent on a machine without DNS client policy
+		log.Debugf("HKEY_LOCAL_MACHINE\\%s does not exist", root)
+		return nil, nil
+	case err != nil:
+		// any other failure has to reach the caller: reporting no rules would
+		// report a successful cleanup while leaving the rules in place
+		return nil, fmt.Errorf("open HKEY_LOCAL_MACHINE\\%s: %w", root, err)
+	}
+	defer closer(k)
+
+	names, err := k.ReadSubKeyNames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("read subkey names: %w", err)
+	}
+
+	var ruleKeys []string
+	for _, name := range names {
+		// registry key names are case insensitive
+		if strings.HasPrefix(strings.ToLower(name), strings.ToLower(NRPTKeyPrefix)) {
+			ruleKeys = append(ruleKeys, name)
+		}
+	}
+
+	return ruleKeys, nil
+}
+
 func removeRegistryKeyFromDNSPolicyConfig(regKeyPath string) error {
 	k, err := registry.OpenKey(registry.LOCAL_MACHINE, regKeyPath, registry.QUERY_VALUE)
 	if err != nil {
@@ -613,7 +656,7 @@ func refreshGroupPolicy() error {
 	)
 
 	if ret == 0 {
-		if err != nil && !errors.Is(err, syscall.Errno(0)) {
+		if !errors.Is(err, syscall.Errno(0)) {
 			return fmt.Errorf("RefreshPolicyEx failed: %w", err)
 		}
 		return fmt.Errorf("RefreshPolicyEx failed")

client/internal/dns/host_windows_test.go

@@ -27,7 +27,7 @@ func TestNRPTEntriesCleanupOnConfigChange(t *testing.T) {
 
 	// Create a test interface registry key so updateSearchDomains doesn't fail
 	testGUID := "{12345678-1234-1234-1234-123456789ABC}"
-	interfacePath := `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\` + testGUID
+	interfacePath := InterfaceConfigPath + `\` + testGUID
 	testKey, _, err := registry.CreateKey(registry.LOCAL_MACHINE, interfacePath, registry.SET_VALUE)
 	require.NoError(t, err, "Should create test interface registry key")
 	testKey.Close()
@@ -59,7 +59,7 @@ func TestNRPTEntriesCleanupOnConfigChange(t *testing.T) {
 	require.NoError(t, err)
 
 	// Verify 3 NRPT rules exist
-	assert.Equal(t, 3, cfg.nrptEntryCount, "Should create 3 NRPT rules for 125 domains")
+	assert.Equal(t, 3, countNRPTRuleKeys(t), "Should create 3 NRPT rules for 125 domains")
 	for i := 0; i < 3; i++ {
 		exists, err := registryKeyExists(fmt.Sprintf("%s-%d", dnsPolicyConfigMatchPath, i))
 		require.NoError(t, err)
@@ -84,7 +84,7 @@ func TestNRPTEntriesCleanupOnConfigChange(t *testing.T) {
 	require.NoError(t, err)
 
 	// Verify first 2 NRPT rules exist
-	assert.Equal(t, 2, cfg.nrptEntryCount, "Should create 2 NRPT rules for 75 domains")
+	assert.Equal(t, 2, countNRPTRuleKeys(t), "Should create 2 NRPT rules for 75 domains")
 	for i := 0; i < 2; i++ {
 		exists, err := registryKeyExists(fmt.Sprintf("%s-%d", dnsPolicyConfigMatchPath, i))
 		require.NoError(t, err)
@@ -109,9 +109,65 @@ func registryKeyExists(path string) (bool, error) {
 	return true, nil
 }
 
+// TestNRPTCleanupWithoutRuleCount verifies that rules written by a previous run
+// are removed by a configurator that has no record of how many there are: an
+// unclean exit loses the in-memory count and a clean disconnect deletes the
+// persisted one, so cleanup cannot depend on either.
+func TestNRPTCleanupWithoutRuleCount(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping registry integration test in short mode")
+	}
+
+	defer cleanupRegistryKeys(t)
+	cleanupRegistryKeys(t)
+
+	testIP := netip.MustParseAddr("100.64.0.1")
+
+	// 75 domains produce two indexed rules, as the current layout does
+	domains := make([]string, 75)
+	for i := range domains {
+		domains[i] = fmt.Sprintf(".domain%d.com", i+1)
+	}
+
+	previousRun := &registryConfigurator{}
+	require.NoError(t, previousRun.addDNSMatchPolicy(domains, testIP))
+
+	// the unsuffixed key an older version would have written
+	require.NoError(t, previousRun.configureDNSPolicy(dnsPolicyConfigMatchPath, []string{".legacy.example.com"}, testIP))
+
+	// a policy owned by someone else, which cleanup must not touch
+	foreignPath := DNSPolicyConfigRoot + `\DnsPolicyConfigTestForeign`
+	foreignKey, _, err := registry.CreateKey(registry.LOCAL_MACHINE, foreignPath, registry.SET_VALUE)
+	require.NoError(t, err, "Should create foreign policy key")
+	foreignKey.Close()
+	defer func() {
+		_ = registry.DeleteKey(registry.LOCAL_MACHINE, foreignPath)
+	}()
+
+	require.Equal(t, 3, countNRPTRuleKeys(t), "Should have two indexed rules and the legacy one")
+
+	// a configurator that never applied a DNS config, as one built after a
+	// restart or from a shutdown state without a count is
+	freshRun := &registryConfigurator{}
+	require.NoError(t, freshRun.removeDNSMatchPolicies())
+
+	assert.Equal(t, 0, countNRPTRuleKeys(t), "Should remove every rule left by the previous run")
+
+	exists, err := registryKeyExists(foreignPath)
+	require.NoError(t, err)
+	assert.True(t, exists, "Should not remove a policy that is not ours")
+}
+
+func countNRPTRuleKeys(t *testing.T) int {
+	t.Helper()
+
+	names, err := listNRPTRuleKeys(DNSPolicyConfigRoot)
+	require.NoError(t, err, "Should list NRPT rule keys")
+	return len(names)
+}
+
 func cleanupRegistryKeys(*testing.T) {
-	// Clean up more entries to account for batching tests with many domains
-	cfg := &registryConfigurator{nrptEntryCount: 20}
+	cfg := &registryConfigurator{}
 	_ = cfg.removeDNSMatchPolicies()
 }
 
@@ -128,7 +184,7 @@ func TestNRPTDomainBatching(t *testing.T) {
 
 	// Create a test interface registry key so updateSearchDomains doesn't fail
 	testGUID := "{12345678-1234-1234-1234-123456789ABC}"
-	interfacePath := `SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\` + testGUID
+	interfacePath := InterfaceConfigPath + `\` + testGUID
 	testKey, _, err := registry.CreateKey(registry.LOCAL_MACHINE, interfacePath, registry.SET_VALUE)
 	require.NoError(t, err, "Should create test interface registry key")
 	testKey.Close()
@@ -197,7 +253,7 @@ func TestNRPTDomainBatching(t *testing.T) {
 			require.NoError(t, err)
 
 			// Verify that exactly expectedRuleCount rules were created
-			assert.Equal(t, tc.expectedRuleCount, cfg.nrptEntryCount,
+			assert.Equal(t, tc.expectedRuleCount, countNRPTRuleKeys(t),
 				"Should create %d NRPT rules for %d domains", tc.expectedRuleCount, tc.domainCount)
 
 			// Verify all expected rules exist

client/internal/dns/interface_index.go

@@ -0,0 +1,15 @@
+package dns
+
+import (
+	"fmt"
+	"net"
+)
+
+func getInterfaceIndex(interfaceName string) (int, error) {
+	iface, err := net.InterfaceByName(interfaceName)
+	if err != nil {
+		return 0, fmt.Errorf("lookup interface %q: %w", interfaceName, err)
+	}
+
+	return iface.Index, nil
+}

client/internal/dns/interface_index_test.go

@@ -0,0 +1,35 @@
+package dns
+
+import (
+	"net"
+	"testing"
+)
+
+func TestGetInterfaceIndexExisting(t *testing.T) {
+	interfaces, err := net.Interfaces()
+	if err != nil {
+		t.Fatalf("list network interfaces: %v", err)
+	}
+	if len(interfaces) == 0 {
+		t.Fatal("expected at least one network interface")
+	}
+
+	iface := interfaces[0]
+	index, err := getInterfaceIndex(iface.Name)
+	if err != nil {
+		t.Fatalf("look up existing interface %q: %v", iface.Name, err)
+	}
+	if index != iface.Index {
+		t.Fatalf("expected interface index %d, got %d", iface.Index, index)
+	}
+}
+
+func TestGetInterfaceIndexMissing(t *testing.T) {
+	index, err := getInterfaceIndex("netbird-interface-that-does-not-exist")
+	if index != 0 {
+		t.Fatalf("expected missing interface index to be 0, got %d", index)
+	}
+	if err == nil {
+		t.Fatal("expected missing interface lookup to return an error")
+	}
+}

client/internal/dns/local/local.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net"
 	"net/netip"
+	"os"
 	"slices"
 	"strings"
 	"sync"
@@ -36,7 +37,43 @@ type resolver interface {
 // record is left alone (it points at something outside our mesh, e.g.
 // a non-peer upstream).
 type PeerConnectivity interface {
-	IsConnectedByIP(ip string) (known, connected bool)
+	IsConnectedByIP(ip netip.Addr) (known, connected bool)
+}
+
+// PeerActivator wakes lazy-connection peers on demand. The local resolver calls
+// it with the tunnel IPs an answer points at, so a peer that is idle (lazily
+// disconnected) starts connecting at DNS-resolution time rather than racing the
+// client's first request packet. nil disables warm-up.
+type PeerActivator interface {
+	// ActivatePeersByIP triggers wake-up for the peer(s) owning addrs and blocks
+	// until one is connected or ctx (a short per-query budget) expires. It is a
+	// fast no-op for unknown or already-connected addresses.
+	ActivatePeersByIP(ctx context.Context, addrs []netip.Addr)
+}
+
+const (
+	defaultLazyWarmupTimeout = 2 * time.Second
+	envLazyWarmupTimeout     = "NB_DNS_LAZY_WARMUP_TIMEOUT"
+)
+
+// lazyWarmupTimeoutFromEnv returns the per-query budget for waking a
+// lazy-connection peer a DNS answer points at. Tunable via
+// NB_DNS_LAZY_WARMUP_TIMEOUT (a Go duration). Parsed once at construction time.
+func lazyWarmupTimeoutFromEnv() time.Duration {
+	v := os.Getenv(envLazyWarmupTimeout)
+	if v == "" {
+		return defaultLazyWarmupTimeout
+	}
+	d, err := time.ParseDuration(v)
+	if err != nil {
+		log.Warnf("invalid %s value %q, using default %s: %v", envLazyWarmupTimeout, v, defaultLazyWarmupTimeout, err)
+		return defaultLazyWarmupTimeout
+	}
+	if d <= 0 {
+		log.Warnf("non-positive %s value %q, using default %s", envLazyWarmupTimeout, v, defaultLazyWarmupTimeout)
+		return defaultLazyWarmupTimeout
+	}
+	return d
 }
 
 type Resolver struct {
@@ -51,6 +88,12 @@ type Resolver struct {
 	// filter and preserves the legacy "return whatever is registered"
 	// behaviour for callers that never wire a status source.
 	peerConn PeerConnectivity
+	// peerActivator, when non-nil, is called at resolution time to warm the
+	// lazy connection to the peer(s) an answer points at. nil disables warm-up.
+	peerActivator PeerActivator
+	// warmupTimeout is the per-query budget for the lazy-connection warm-up
+	// wait, resolved from the environment once at construction time.
+	warmupTimeout time.Duration
 
 	ctx    context.Context
 	cancel context.CancelFunc
@@ -59,11 +102,12 @@ type Resolver struct {
 func NewResolver() *Resolver {
 	ctx, cancel := context.WithCancel(context.Background())
 	return &Resolver{
-		records: make(map[dns.Question][]dns.RR),
-		domains: make(map[domain.Domain]struct{}),
-		zones:   make(map[domain.Domain]bool),
-		ctx:     ctx,
-		cancel:  cancel,
+		records:       make(map[dns.Question][]dns.RR),
+		domains:       make(map[domain.Domain]struct{}),
+		zones:         make(map[domain.Domain]bool),
+		warmupTimeout: lazyWarmupTimeoutFromEnv(),
+		ctx:           ctx,
+		cancel:        cancel,
 	}
 }
 
@@ -76,6 +120,14 @@ func (d *Resolver) SetPeerConnectivity(p PeerConnectivity) {
 	d.peerConn = p
 }
 
+// SetPeerActivator wires the DNS-time lazy-connection warm-up. Pass nil to
+// disable. Safe to call multiple times; the latest value wins.
+func (d *Resolver) SetPeerActivator(a PeerActivator) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	d.peerActivator = a
+}
+
 func (d *Resolver) MatchSubdomains() bool {
 	return true
 }
@@ -122,6 +174,9 @@ func (d *Resolver) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 	replyMessage.RecursionAvailable = true
 
 	result := d.lookupRecords(logger, question)
+	// Warm before filtering: activation flips a lazily-idle target to connected,
+	// which then lets it survive the disconnected-peer filter below.
+	d.warmLazyPeers(question, result.records)
 	result.records = d.filterDisconnectedPeerAnswers(logger, question, result.records)
 	replyMessage.Authoritative = !result.hasExternalData
 	replyMessage.Answer = result.records
@@ -482,7 +537,7 @@ func (d *Resolver) logDNSError(logger *log.Entry, hostname string, qtype uint16,
 // completely when every proxy peer is offline (the upstream may still
 // be reachable some other way, or the peerstore may be stale).
 func (d *Resolver) filterDisconnectedPeerAnswers(logger *log.Entry, question dns.Question, records []dns.RR) []dns.RR {
-	if len(records) == 0 {
+	if len(records) < 2 {
 		return records
 	}
 	d.mu.RLock()
@@ -495,8 +550,8 @@ func (d *Resolver) filterDisconnectedPeerAnswers(logger *log.Entry, question dns
 	kept := make([]dns.RR, 0, len(records))
 	var dropped int
 	for _, rr := range records {
-		ip := extractRecordIP(rr)
-		if ip == "" {
+		ip, ok := extractRecordAddr(rr)
+		if !ok {
 			kept = append(kept, rr)
 			continue
 		}
@@ -518,22 +573,57 @@ func (d *Resolver) filterDisconnectedPeerAnswers(logger *log.Entry, question dns
 	return kept
 }
 
-// extractRecordIP returns the dotted-decimal / colon-hex IP carried by
-// an A or AAAA record, or "" for any other record type.
-func extractRecordIP(rr dns.RR) string {
+// warmLazyPeers triggers lazy-connection wake-up for the peers a resolved
+// answer points at and waits briefly for one to connect, so the caller's first
+// request doesn't race the connection establishment. Warm-up is scoped to
+// match-only (non-authoritative) zones — the synthesized private-service zones
+// and user-created zones whose records point at specific peers. The account's
+// peer zone is authoritative, so plain peer-name lookups never trigger warm-up;
+// otherwise resolving any peer's name would wake its idle connection, defeating
+// laziness mesh-wide. No-op when no activator is wired (lazy connections
+// disabled) or the answer carries no peer IPs.
+func (d *Resolver) warmLazyPeers(question dns.Question, records []dns.RR) {
+	if len(records) < 2 {
+		return
+	}
+	d.mu.RLock()
+	activator := d.peerActivator
+	var nonAuth, found bool
+	if activator != nil {
+		nonAuth, found = d.findZone(question.Name)
+	}
+	d.mu.RUnlock()
+	if activator == nil || !found || !nonAuth {
+		return
+	}
+
+	var addrs []netip.Addr
+	for _, rr := range records {
+		if addr, ok := extractRecordAddr(rr); ok {
+			addrs = append(addrs, addr)
+		}
+	}
+	if len(addrs) == 0 {
+		return
+	}
+
+	ctx, cancel := context.WithTimeout(d.ctx, d.warmupTimeout)
+	defer cancel()
+	activator.ActivatePeersByIP(ctx, addrs)
+}
+
+// extractRecordAddr returns the IP address carried by an A or AAAA record.
+// ok is false for any other record type or a record with no address.
+func extractRecordAddr(rr dns.RR) (netip.Addr, bool) {
 	switch r := rr.(type) {
 	case *dns.A:
-		if r.A == nil {
-			return ""
-		}
-		return r.A.String()
+		addr, ok := netip.AddrFromSlice(r.A)
+		return addr.Unmap(), ok
 	case *dns.AAAA:
-		if r.AAAA == nil {
-			return ""
-		}
-		return r.AAAA.String()
+		addr, ok := netip.AddrFromSlice(r.AAAA)
+		return addr.Unmap(), ok
 	}
-	return ""
+	return netip.Addr{}, false
 }
 
 // Update replaces all zones and their records

client/internal/dns/local/local_test.go

@@ -37,8 +37,8 @@ type mockPeerConnectivity struct {
 	byIP map[string]struct{ known, connected bool }
 }
 
-func (m mockPeerConnectivity) IsConnectedByIP(ip string) (known, connected bool) {
-	v, ok := m.byIP[ip]
+func (m mockPeerConnectivity) IsConnectedByIP(ip netip.Addr) (known, connected bool) {
+	v, ok := m.byIP[ip.String()]
 	if !ok {
 		return false, false
 	}
@@ -2738,6 +2738,17 @@ func TestLocalResolver_FilterDisconnectedPeerAnswers(t *testing.T) {
 			connByIP:    nil,
 			wantInOrder: []string{"100.64.0.10", "100.64.0.11"},
 		},
+		{
+			// A single answer is never filtered: dropping it would only
+			// trigger the empty-answer escape hatch, so the fast path
+			// returns it untouched.
+			name:    "single disconnected answer passes through",
+			records: []nbdns.SimpleRecord{disconnectedRec},
+			connByIP: map[string]ipState{
+				"100.64.0.11": {known: true, connected: false},
+			},
+			wantInOrder: []string{"100.64.0.11"},
+		},
 	}
 
 	for _, tc := range tests {

client/internal/dns/local/warmup_test.go

@@ -0,0 +1,204 @@
+package local
+
+import (
+	"context"
+	"net"
+	"net/netip"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/miekg/dns"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/internal/dns/test"
+	nbdns "github.com/netbirdio/netbird/dns"
+)
+
+// recordingActivator records the addresses it was asked to warm and returns
+// immediately, so ServeDNS is not blocked by the test.
+type recordingActivator struct {
+	mu     sync.Mutex
+	called bool
+	addrs  []netip.Addr
+}
+
+func (r *recordingActivator) ActivatePeersByIP(_ context.Context, addrs []netip.Addr) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+	r.called = true
+	r.addrs = append(r.addrs, addrs...)
+}
+
+func serveA(t *testing.T, resolver *Resolver, name string) *dns.Msg {
+	t.Helper()
+	var resp *dns.Msg
+	w := &test.MockResponseWriter{WriteMsgFunc: func(m *dns.Msg) error { resp = m; return nil }}
+	resolver.ServeDNS(w, new(dns.Msg).SetQuestion(name, dns.TypeA))
+	return resp
+}
+
+// serviceZone registers rec in a match-only (non-authoritative) zone, the shape
+// the synthesized private-service zones arrive in.
+func serviceZone(t *testing.T, resolver *Resolver, zone string, records ...nbdns.SimpleRecord) {
+	t.Helper()
+	resolver.Update([]nbdns.CustomZone{{
+		Domain:           zone,
+		Records:          records,
+		NonAuthoritative: true,
+	}})
+}
+
+func TestLocalResolver_WarmsLazyPeerOnResolve(t *testing.T) {
+	// Warm-up fires only for multi-record answers (the HA / round-robin shape of
+	// the synthesized private-service zones), so register two peer targets.
+	const name = "svc.proxy.netbird.cloud."
+	recs := []nbdns.SimpleRecord{
+		{Name: name, Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "100.64.0.7"},
+		{Name: name, Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "100.64.0.8"},
+	}
+	resolver := NewResolver()
+	serviceZone(t, resolver, "proxy.netbird.cloud", recs...)
+
+	act := &recordingActivator{}
+	resolver.SetPeerActivator(act)
+
+	resp := serveA(t, resolver, name)
+	require.NotNil(t, resp, "resolver must answer")
+	require.NotEmpty(t, resp.Answer, "answer must carry the A records")
+
+	act.mu.Lock()
+	defer act.mu.Unlock()
+	assert.True(t, act.called, "activator must be invoked for a multi-record service-zone answer")
+	assert.Contains(t, act.addrs, netip.MustParseAddr("100.64.0.7"), "activator must receive the first peer IP")
+	assert.Contains(t, act.addrs, netip.MustParseAddr("100.64.0.8"), "activator must receive the second peer IP")
+}
+
+func TestLocalResolver_NoWarmupForSingleRecord(t *testing.T) {
+	// A single-record answer does not trigger warm-up; the resolver only warms
+	// multi-record answers.
+	rec := nbdns.SimpleRecord{Name: "svc.proxy.netbird.cloud.", Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "100.64.0.7"}
+	resolver := NewResolver()
+	serviceZone(t, resolver, "proxy.netbird.cloud", rec)
+
+	act := &recordingActivator{}
+	resolver.SetPeerActivator(act)
+
+	resp := serveA(t, resolver, rec.Name)
+	require.NotNil(t, resp, "resolver must answer")
+	require.NotEmpty(t, resp.Answer, "answer must carry the A record")
+
+	act.mu.Lock()
+	defer act.mu.Unlock()
+	assert.False(t, act.called, "activator must not be invoked for a single-record answer")
+}
+
+func TestLocalResolver_NoActivatorNoWarmup(t *testing.T) {
+	// With no activator wired the resolver behaves exactly as before.
+	rec := nbdns.SimpleRecord{Name: "svc.proxy.netbird.cloud.", Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "100.64.0.7"}
+	resolver := NewResolver()
+	serviceZone(t, resolver, "proxy.netbird.cloud", rec)
+
+	resp := serveA(t, resolver, rec.Name)
+	require.NotNil(t, resp, "resolver must still answer without an activator")
+	require.NotEmpty(t, resp.Answer, "answer must carry the A record")
+}
+
+func TestLocalResolver_NoWarmupForMissingRecord(t *testing.T) {
+	// A query that resolves to nothing must not invoke the activator (no IPs).
+	resolver := NewResolver()
+	serviceZone(t, resolver, "proxy.netbird.cloud",
+		nbdns.SimpleRecord{Name: "svc.proxy.netbird.cloud.", Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "100.64.0.7"})
+
+	act := &recordingActivator{}
+	resolver.SetPeerActivator(act)
+
+	serveA(t, resolver, "absent.proxy.netbird.cloud.")
+
+	act.mu.Lock()
+	defer act.mu.Unlock()
+	assert.False(t, act.called, "activator must not be invoked when there is no answer")
+}
+
+func TestLocalResolver_NoWarmupInAuthoritativeZone(t *testing.T) {
+	// The account's peer zone is authoritative; resolving a peer's name there
+	// must not wake its lazy connection — warm-up is scoped to match-only
+	// (non-authoritative) zones such as the synthesized private-service zones.
+	// Use a multi-record answer so the authoritative-zone scoping is the only
+	// reason warm-up is skipped, not the single-record guard.
+	const name = "peer.netbird.cloud."
+	recs := []nbdns.SimpleRecord{
+		{Name: name, Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "100.64.0.9"},
+		{Name: name, Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "100.64.0.10"},
+	}
+	resolver := NewResolver()
+	resolver.Update([]nbdns.CustomZone{{
+		Domain:  "netbird.cloud",
+		Records: recs,
+	}})
+
+	act := &recordingActivator{}
+	resolver.SetPeerActivator(act)
+
+	resp := serveA(t, resolver, name)
+	require.NotNil(t, resp, "resolver must answer")
+	require.NotEmpty(t, resp.Answer, "answer must carry the A records")
+
+	act.mu.Lock()
+	defer act.mu.Unlock()
+	assert.False(t, act.called, "activator must not be invoked for authoritative-zone answers")
+}
+
+func TestLazyWarmupTimeoutFromEnv(t *testing.T) {
+	tests := []struct {
+		name   string
+		value  string
+		envSet bool
+		want   time.Duration
+	}{
+		{name: "unset uses default", want: defaultLazyWarmupTimeout},
+		{name: "valid overrides", value: "5s", envSet: true, want: 5 * time.Second},
+		{name: "invalid falls back", value: "not-a-duration", envSet: true, want: defaultLazyWarmupTimeout},
+		{name: "negative falls back", value: "-1s", envSet: true, want: defaultLazyWarmupTimeout},
+		{name: "zero falls back", value: "0s", envSet: true, want: defaultLazyWarmupTimeout},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if tt.envSet {
+				t.Setenv(envLazyWarmupTimeout, tt.value)
+			}
+			assert.Equal(t, tt.want, lazyWarmupTimeoutFromEnv())
+			assert.Equal(t, tt.want, NewResolver().warmupTimeout, "constructor must resolve the timeout once")
+		})
+	}
+}
+
+func TestExtractRecordAddr(t *testing.T) {
+	t.Run("A record yields unmapped v4", func(t *testing.T) {
+		// net.ParseIP returns the 16-byte v4-in-v6 form, the same shape
+		// miekg/dns stores after parsing an A record; the extracted address
+		// must compare equal to a plain v4 netip.Addr.
+		addr, ok := extractRecordAddr(&dns.A{A: net.ParseIP("100.64.0.7")})
+		require.True(t, ok)
+		assert.True(t, addr.Is4())
+		assert.Equal(t, netip.MustParseAddr("100.64.0.7"), addr)
+	})
+
+	t.Run("AAAA record yields v6", func(t *testing.T) {
+		addr, ok := extractRecordAddr(&dns.AAAA{AAAA: net.ParseIP("fd00::1")})
+		require.True(t, ok)
+		assert.Equal(t, netip.MustParseAddr("fd00::1"), addr)
+	})
+
+	t.Run("A record without address", func(t *testing.T) {
+		_, ok := extractRecordAddr(&dns.A{})
+		assert.False(t, ok)
+	})
+
+	t.Run("non-address record", func(t *testing.T) {
+		_, ok := extractRecordAddr(&dns.CNAME{Target: "target.netbird.cloud."})
+		assert.False(t, ok)
+	})
+}

client/internal/dns/mgmt/mgmt.go

@@ -51,13 +51,20 @@ type cachedRecord struct {
 }
 
 // Resolver caches critical NetBird infrastructure domains.
-// records, refreshing, mgmtDomain and serverDomains are all guarded by mutex.
+// records, refreshing, failedResolves, mgmtDomain and serverDomains are all
+// guarded by mutex.
 type Resolver struct {
 	records       map[dns.Question]*cachedRecord
 	mgmtDomain    *domain.Domain
 	serverDomains *dnsconfig.ServerDomains
 	mutex         sync.RWMutex
 
+	// failedResolves records the last failed initial resolve per domain so a
+	// domain that never resolves isn't retried on every server-domains update
+	// until refreshBackoff elapses. Entries are cleared on success and pruned
+	// to the current server-domains set.
+	failedResolves map[domain.Domain]time.Time
+
 	chain            ChainResolver
 	chainMaxPriority int
 	refreshGroup     singleflight.Group
@@ -76,9 +83,10 @@ type Resolver struct {
 // NewResolver creates a new management domains cache resolver.
 func NewResolver() *Resolver {
 	return &Resolver{
-		records:    make(map[dns.Question]*cachedRecord),
-		refreshing: make(map[dns.Question]*atomic.Bool),
-		cacheTTL:   resolveCacheTTL(),
+		records:        make(map[dns.Question]*cachedRecord),
+		refreshing:     make(map[dns.Question]*atomic.Bool),
+		failedResolves: make(map[domain.Domain]time.Time),
+		cacheTTL:       resolveCacheTTL(),
 	}
 }
 
@@ -173,7 +181,9 @@ func (m *Resolver) continueToNext(w dns.ResponseWriter, r *dns.Msg) {
 
 // AddDomain resolves a domain and stores its A/AAAA records in the cache.
 // A family that resolves NODATA (nil err, zero records) evicts any stale
-// entry for that qtype.
+// entry for that qtype. When one family hard-errors while the other succeeds,
+// the resolved family is still cached but AddDomain returns an error so the
+// caller retries the incomplete resolve rather than treating it as complete.
 func (m *Resolver) AddDomain(ctx context.Context, d domain.Domain) error {
 	dnsName := strings.ToLower(dns.Fqdn(d.PunycodeString()))
 
@@ -203,6 +213,10 @@ func (m *Resolver) AddDomain(ctx context.Context, d domain.Domain) error {
 	log.Debugf("added/updated domain=%s with %d A records and %d AAAA records",
 		d.SafeString(), len(aRecords), len(aaaaRecords))
 
+	if errA != nil || errAAAA != nil {
+		return fmt.Errorf("resolve %s: incomplete, a family failed: %w", d.SafeString(), errors.Join(errA, errAAAA))
+	}
+
 	return nil
 }
 
@@ -462,6 +476,7 @@ func (m *Resolver) RemoveDomain(d domain.Domain) error {
 	delete(m.records, qAAAA)
 	delete(m.refreshing, qA)
 	delete(m.refreshing, qAAAA)
+	delete(m.failedResolves, d)
 
 	log.Debugf("removed domain=%s from cache", d.SafeString())
 	return nil
@@ -505,6 +520,7 @@ func (m *Resolver) UpdateFromServerDomains(ctx context.Context, serverDomains dn
 		allDomains := m.extractDomainsFromServerDomains(updatedServerDomains)
 		currentDomains := m.GetCachedDomains()
 		removedDomains = m.removeStaleDomains(currentDomains, allDomains)
+		m.pruneFailedResolves(allDomains)
 	}
 
 	m.addNewDomains(ctx, newDomains)
@@ -577,13 +593,85 @@ func (m *Resolver) isManagementDomain(domain domain.Domain) bool {
 	return m.mgmtDomain != nil && domain == *m.mgmtDomain
 }
 
-// addNewDomains resolves and caches all domains from the update
+// addNewDomains resolves and caches domains that are not yet in the cache,
+// running the lookups concurrently. Domains already cached are skipped and left
+// to the stale-while-revalidate refresh path, so a sync never re-resolves them
+// synchronously: once NetBird owns the OS resolver the resolve runs through the
+// handler chain and would otherwise dial the managed upstreams under the engine
+// sync lock on every update.
 func (m *Resolver) addNewDomains(ctx context.Context, newDomains domain.List) {
+	var wg sync.WaitGroup
+	seen := make(map[domain.Domain]struct{}, len(newDomains))
 	for _, newDomain := range newDomains {
-		if err := m.AddDomain(ctx, newDomain); err != nil {
-			log.Warnf("failed to add/update domain=%s: %v", newDomain.SafeString(), err)
-		} else {
-			log.Debugf("added/updated management cache domain=%s", newDomain.SafeString())
+		if _, dup := seen[newDomain]; dup {
+			continue
+		}
+		seen[newDomain] = struct{}{}
+
+		if !m.needsResolve(newDomain) {
+			continue
+		}
+
+		wg.Add(1)
+		go func(d domain.Domain) {
+			defer wg.Done()
+			if err := m.AddDomain(ctx, d); err != nil {
+				m.markResolveFailed(d)
+				log.Warnf("failed to add/update domain=%s: %v", d.SafeString(), err)
+				return
+			}
+			m.clearResolveFailed(d)
+			log.Debugf("added/updated management cache domain=%s", d.SafeString())
+		}(newDomain)
+	}
+	wg.Wait()
+}
+
+// needsResolve reports whether d should be resolved now. A recent failed or
+// incomplete resolve gates retries on the backoff even when one family is
+// already cached, so a transiently-failed family is retried instead of being
+// treated as fully resolved. Otherwise a domain with any cached record is left
+// to the stale-while-revalidate refresh path.
+func (m *Resolver) needsResolve(d domain.Domain) bool {
+	dnsName := strings.ToLower(dns.Fqdn(d.PunycodeString()))
+
+	m.mutex.RLock()
+	defer m.mutex.RUnlock()
+
+	if failedAt, ok := m.failedResolves[d]; ok {
+		return time.Since(failedAt) >= refreshBackoff
+	}
+
+	for _, qtype := range []uint16{dns.TypeA, dns.TypeAAAA} {
+		q := dns.Question{Name: dnsName, Qtype: qtype, Qclass: dns.ClassINET}
+		if _, ok := m.records[q]; ok {
+			return false
+		}
+	}
+	return true
+}
+
+func (m *Resolver) markResolveFailed(d domain.Domain) {
+	m.mutex.Lock()
+	m.failedResolves[d] = time.Now()
+	m.mutex.Unlock()
+}
+
+func (m *Resolver) clearResolveFailed(d domain.Domain) {
+	m.mutex.Lock()
+	delete(m.failedResolves, d)
+	m.mutex.Unlock()
+}
+
+// pruneFailedResolves drops failure markers for domains no longer present in
+// the server-domains set, keeping the map bounded to the current set (a
+// failed-only domain has no cached record, so RemoveDomain never sees it).
+func (m *Resolver) pruneFailedResolves(domains domain.List) {
+	m.mutex.Lock()
+	defer m.mutex.Unlock()
+	for d := range m.failedResolves {
+		if !slices.Contains(domains, d) {
+			delete(m.failedResolves, d)
 		}
 	}
 }

client/internal/dns/mgmt/mgmt_refresh_test.go

@@ -21,6 +21,7 @@ type fakeChain struct {
 	mu       sync.Mutex
 	calls    map[string]int
 	answers  map[string][]dns.RR
+	qErr     map[string]error
 	err      error
 	hasRoot  bool
 	onLookup func()
@@ -30,6 +31,7 @@ func newFakeChain() *fakeChain {
 	return &fakeChain{
 		calls:   map[string]int{},
 		answers: map[string][]dns.RR{},
+		qErr:    map[string]error{},
 		hasRoot: true,
 	}
 }
@@ -47,6 +49,9 @@ func (f *fakeChain) ResolveInternal(ctx context.Context, msg *dns.Msg, maxPriori
 	f.calls[key]++
 	answers := f.answers[key]
 	err := f.err
+	if err == nil {
+		err = f.qErr[key]
+	}
 	onLookup := f.onLookup
 	f.mu.Unlock()
 
@@ -75,6 +80,12 @@ func (f *fakeChain) setAnswer(name string, qtype uint16, ip string) {
 	}
 }
 
+func (f *fakeChain) setErr(name string, qtype uint16, err error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.qErr[name+"|"+dns.TypeToString[qtype]] = err
+}
+
 func (f *fakeChain) callCount(name string, qtype uint16) int {
 	f.mu.Lock()
 	defer f.mu.Unlock()

client/internal/dns/mgmt/mgmt_resolve_test.go

@@ -0,0 +1,183 @@
+package mgmt
+
+import (
+	"context"
+	"errors"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/miekg/dns"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	dnsconfig "github.com/netbirdio/netbird/client/internal/dns/config"
+	"github.com/netbirdio/netbird/shared/management/domain"
+)
+
+// A domain already in the cache must not be re-resolved on a subsequent server
+// domains update; it is left to the stale-while-revalidate refresh path.
+func TestResolver_UpdateFromServerDomains_SkipsCached(t *testing.T) {
+	r := NewResolver()
+	chain := newFakeChain()
+	chain.setAnswer("signal.example.com.", dns.TypeA, "10.0.0.2")
+	r.SetChainResolver(chain, 50)
+
+	sd := dnsconfig.ServerDomains{Signal: domain.Domain("signal.example.com")}
+
+	_, err := r.UpdateFromServerDomains(context.Background(), sd)
+	require.NoError(t, err)
+	require.Equal(t, 1, chain.callCount("signal.example.com.", dns.TypeA),
+		"first update must resolve the domain")
+
+	_, err = r.UpdateFromServerDomains(context.Background(), sd)
+	require.NoError(t, err)
+	assert.Equal(t, 1, chain.callCount("signal.example.com.", dns.TypeA),
+		"cached domain must not be re-resolved on a subsequent update")
+}
+
+// New domains in a single update must resolve concurrently rather than serially.
+func TestResolver_AddNewDomains_ResolvesConcurrently(t *testing.T) {
+	r := NewResolver()
+	chain := newFakeChain()
+
+	var inflight, maxInflight atomic.Int32
+	chain.onLookup = func() {
+		n := inflight.Add(1)
+		for {
+			old := maxInflight.Load()
+			if n <= old || maxInflight.CompareAndSwap(old, n) {
+				break
+			}
+		}
+		time.Sleep(50 * time.Millisecond)
+		inflight.Add(-1)
+	}
+
+	relays := []domain.Domain{"a.example.com", "b.example.com", "c.example.com", "d.example.com"}
+	for _, d := range relays {
+		chain.setAnswer(dns.Fqdn(string(d)), dns.TypeA, "10.0.0.2")
+	}
+	r.SetChainResolver(chain, 50)
+
+	start := time.Now()
+	_, err := r.UpdateFromServerDomains(context.Background(), dnsconfig.ServerDomains{Relay: relays})
+	require.NoError(t, err)
+	elapsed := time.Since(start)
+
+	assert.GreaterOrEqual(t, int(maxInflight.Load()), 2, "domains must resolve concurrently")
+	// Serial resolution of 4 domains would take at least 4*50ms; concurrent is far less.
+	assert.Less(t, elapsed, 300*time.Millisecond, "resolution should not be serial")
+}
+
+// A domain that fails to resolve must not be retried on every update; the
+// failure backoff suppresses re-resolution until it expires.
+func TestResolver_UpdateFromServerDomains_BacksOffFailures(t *testing.T) {
+	r := NewResolver()
+	chain := newFakeChain()
+	chain.err = errors.New("resolve boom")
+	r.SetChainResolver(chain, 50)
+
+	sd := dnsconfig.ServerDomains{Signal: domain.Domain("signal.example.com")}
+
+	_, err := r.UpdateFromServerDomains(context.Background(), sd)
+	require.NoError(t, err)
+	require.Equal(t, 1, chain.callCount("signal.example.com.", dns.TypeA),
+		"first update must attempt the resolve")
+
+	_, err = r.UpdateFromServerDomains(context.Background(), sd)
+	require.NoError(t, err)
+	assert.Equal(t, 1, chain.callCount("signal.example.com.", dns.TypeA),
+		"failed resolve must back off and not retry on the next update")
+}
+
+// A domain listed under more than one server-domain type (e.g. STUN and TURN on
+// the same host) must be resolved once per update, not once per occurrence.
+func TestResolver_AddNewDomains_DedupesDuplicateDomains(t *testing.T) {
+	r := NewResolver()
+	chain := newFakeChain()
+	chain.setAnswer("dup.example.com.", dns.TypeA, "10.0.0.9")
+	r.SetChainResolver(chain, 50)
+
+	sd := dnsconfig.ServerDomains{
+		Stuns: []domain.Domain{"dup.example.com"},
+		Turns: []domain.Domain{"dup.example.com"},
+	}
+
+	_, err := r.UpdateFromServerDomains(context.Background(), sd)
+	require.NoError(t, err)
+	assert.Equal(t, 1, chain.callCount("dup.example.com.", dns.TypeA),
+		"a domain appearing under multiple server-domain types must resolve once")
+}
+
+// A failure marker must be dropped once its domain leaves the server-domains set
+// so the map stays bounded to the current set.
+func TestResolver_UpdateFromServerDomains_PrunesFailedResolves(t *testing.T) {
+	r := NewResolver()
+	chain := newFakeChain()
+	chain.err = errors.New("resolve boom")
+	r.SetChainResolver(chain, 50)
+
+	_, err := r.UpdateFromServerDomains(context.Background(), dnsconfig.ServerDomains{Signal: domain.Domain("gone.example.com")})
+	require.NoError(t, err)
+	r.mutex.RLock()
+	_, marked := r.failedResolves[domain.Domain("gone.example.com")]
+	r.mutex.RUnlock()
+	require.True(t, marked, "failed resolve must be recorded")
+
+	_, err = r.UpdateFromServerDomains(context.Background(), dnsconfig.ServerDomains{Signal: domain.Domain("other.example.com")})
+	require.NoError(t, err)
+	r.mutex.RLock()
+	_, stillMarked := r.failedResolves[domain.Domain("gone.example.com")]
+	r.mutex.RUnlock()
+	assert.False(t, stillMarked, "failure marker for a domain no longer in the set must be pruned")
+}
+
+// When one family hard-errors while the other resolves, the domain is cached
+// for the working family but recorded as incomplete so the failed family is
+// retried under backoff instead of being treated as fully resolved forever.
+func TestResolver_AddNewDomains_RetriesPartialFamilyFailure(t *testing.T) {
+	d := domain.Domain("relay.example.com")
+	r := NewResolver()
+	chain := newFakeChain()
+	chain.setAnswer("relay.example.com.", dns.TypeA, "10.0.0.2")
+	chain.setErr("relay.example.com.", dns.TypeAAAA, errors.New("servfail"))
+	r.SetChainResolver(chain, 50)
+
+	_, err := r.UpdateFromServerDomains(context.Background(), dnsconfig.ServerDomains{Relay: []domain.Domain{d}})
+	require.NoError(t, err)
+
+	r.mutex.RLock()
+	_, aCached := r.records[dns.Question{Name: "relay.example.com.", Qtype: dns.TypeA, Qclass: dns.ClassINET}]
+	_, marked := r.failedResolves[d]
+	r.mutex.RUnlock()
+	require.True(t, aCached, "the working family must still be cached")
+	require.True(t, marked, "a partial failure must be recorded so the failed family is retried")
+
+	assert.False(t, r.needsResolve(d), "within the backoff window the domain is not retried")
+
+	r.mutex.Lock()
+	r.failedResolves[d] = time.Now().Add(-2 * refreshBackoff)
+	r.mutex.Unlock()
+	assert.True(t, r.needsResolve(d), "after the backoff elapses the domain is retried to pick up the missing family")
+}
+
+// A family that returns NODATA (legitimately absent, e.g. an IPv4-only host) is
+// not a failure: the domain must not be marked for retry, otherwise it would be
+// re-resolved on every sync.
+func TestResolver_AddNewDomains_NodataIsNotFailure(t *testing.T) {
+	d := domain.Domain("v4only.example.com")
+	r := NewResolver()
+	chain := newFakeChain()
+	chain.setAnswer("v4only.example.com.", dns.TypeA, "10.0.0.2")
+	r.SetChainResolver(chain, 50)
+
+	_, err := r.UpdateFromServerDomains(context.Background(), dnsconfig.ServerDomains{Relay: []domain.Domain{d}})
+	require.NoError(t, err)
+
+	r.mutex.RLock()
+	_, marked := r.failedResolves[d]
+	r.mutex.RUnlock()
+	assert.False(t, marked, "a NODATA family must not be recorded as a failure")
+	assert.False(t, r.needsResolve(d), "an IPv4-only host must not be re-resolved on later syncs")
+}

client/internal/dns/mock_server.go

@@ -8,6 +8,7 @@ import (
 	"github.com/miekg/dns"
 
 	dnsconfig "github.com/netbirdio/netbird/client/internal/dns/config"
+	"github.com/netbirdio/netbird/client/internal/dns/local"
 	nbdns "github.com/netbirdio/netbird/dns"
 	"github.com/netbirdio/netbird/route"
 	"github.com/netbirdio/netbird/shared/management/domain"
@@ -92,6 +93,11 @@ func (m *MockServer) SetFirewall(Firewall) {
 	// Mock implementation - no-op
 }
 
+// SetPeerActivator mock implementation of SetPeerActivator from Server interface
+func (m *MockServer) SetPeerActivator(local.PeerActivator) {
+	// Mock implementation - no-op
+}
+
 // BeginBatch mock implementation of BeginBatch from Server interface
 func (m *MockServer) BeginBatch() {
 	// Mock implementation - no-op

client/internal/dns/notifier.go

@@ -51,7 +51,5 @@ func (n *notifier) notify() {
 		return
 	}
 
-	go func(l listener.NetworkChangeListener) {
-		l.OnNetworkChanged("")
-	}(n.listener)
+	n.listener.OnNetworkChanged("")
 }

client/internal/dns/response_writer_test.go

@@ -4,7 +4,7 @@ import (
 	"net"
 	"testing"
 
-	"github.com/golang/mock/gomock"
+	"go.uber.org/mock/gomock"
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
 	"github.com/miekg/dns"

client/internal/dns/resutil/resolve.go

@@ -8,12 +8,17 @@ import (
 	"errors"
 	"net"
 	"net/netip"
+	"slices"
 	"strings"
 
 	"github.com/miekg/dns"
 	log "github.com/sirupsen/logrus"
 )
 
+// errNoSuitableAddress mirrors the unexported error string the net package
+// uses when a resolved host has no addresses of the requested family.
+const errNoSuitableAddress = "no suitable address found"
+
 // GenerateRequestID creates a random 8-character hex string for request tracing.
 func GenerateRequestID() string {
 	bytes := make([]byte, 4)
@@ -126,6 +131,14 @@ func LookupIP(ctx context.Context, r resolver, network, host string, qtype uint1
 }
 
 func getRcodeForError(ctx context.Context, r resolver, host string, qtype uint16, err error) int {
+	// The net package returns this AddrError when the host resolves but has
+	// no addresses of the requested family. The domain exists, so answer
+	// NODATA instead of SERVFAIL.
+	var addrErr *net.AddrError
+	if errors.As(err, &addrErr) && addrErr.Err == errNoSuitableAddress {
+		return dns.RcodeSuccess
+	}
+
 	var dnsErr *net.DNSError
 	if !errors.As(err, &dnsErr) {
 		return dns.RcodeServerFailure
@@ -155,7 +168,10 @@ func getRcodeForNotFound(ctx context.Context, r resolver, domain string, origina
 	case dns.TypeA:
 		alternativeNetwork = "ip6"
 	default:
-		return dns.RcodeNameError
+		// Non-address types reach LookupIP only unexpectedly; without an
+		// address pair to probe we cannot prove the name is absent, so answer
+		// NODATA rather than a poisoning NXDOMAIN.
+		return dns.RcodeSuccess
 	}
 
 	if _, err := r.LookupNetIP(ctx, alternativeNetwork, domain); err != nil {
@@ -172,6 +188,230 @@ func getRcodeForNotFound(ctx context.Context, r resolver, domain string, origina
 	return dns.RcodeSuccess
 }
 
+// RecordResolver is the host resolver surface used to forward non-address
+// record queries. net.DefaultResolver satisfies it.
+type RecordResolver interface {
+	LookupMX(ctx context.Context, name string) ([]*net.MX, error)
+	LookupTXT(ctx context.Context, name string) ([]string, error)
+	LookupNS(ctx context.Context, name string) ([]*net.NS, error)
+	LookupSRV(ctx context.Context, service, proto, name string) (string, []*net.SRV, error)
+	LookupCNAME(ctx context.Context, host string) (string, error)
+	LookupAddr(ctx context.Context, addr string) ([]string, error)
+}
+
+// LookupRecords resolves a non-address DNS record type through the host
+// resolver and returns the resource records and the DNS rcode. Types the host
+// resolver cannot answer (anything not covered by the net.Resolver Lookup*
+// methods) yield NODATA so that a routed name is never poisoned with NXDOMAIN
+// for an unsupported type.
+func LookupRecords(ctx context.Context, r RecordResolver, name string, qtype uint16, ttl uint32) ([]dns.RR, int) {
+	fqdn := dns.Fqdn(name)
+
+	switch qtype {
+	case dns.TypeMX:
+		return lookupMX(ctx, r, name, fqdn, ttl)
+	case dns.TypeTXT:
+		return lookupTXT(ctx, r, name, fqdn, ttl)
+	case dns.TypeNS:
+		return lookupNS(ctx, r, name, fqdn, ttl)
+	case dns.TypeSRV:
+		return lookupSRV(ctx, r, name, fqdn, ttl)
+	case dns.TypeCNAME:
+		return lookupCNAME(ctx, r, name, fqdn, ttl)
+	case dns.TypePTR:
+		return lookupPTR(ctx, r, name, fqdn, ttl)
+	default:
+		return nil, dns.RcodeSuccess
+	}
+}
+
+func recordHeader(fqdn string, rrtype uint16, ttl uint32) dns.RR_Header {
+	return dns.RR_Header{Name: fqdn, Rrtype: rrtype, Class: dns.ClassINET, Ttl: ttl}
+}
+
+func lookupMX(ctx context.Context, r RecordResolver, name, fqdn string, ttl uint32) ([]dns.RR, int) {
+	recs, err := r.LookupMX(ctx, name)
+	if err != nil {
+		return nil, rcodeForRecordError(err)
+	}
+	rrs := make([]dns.RR, 0, len(recs))
+	for _, mx := range recs {
+		rrs = append(rrs, &dns.MX{
+			Hdr:        recordHeader(fqdn, dns.TypeMX, ttl),
+			Preference: mx.Pref,
+			Mx:         dns.Fqdn(mx.Host),
+		})
+	}
+	return rrs, dns.RcodeSuccess
+}
+
+func lookupTXT(ctx context.Context, r RecordResolver, name, fqdn string, ttl uint32) ([]dns.RR, int) {
+	recs, err := r.LookupTXT(ctx, name)
+	if err != nil {
+		return nil, rcodeForRecordError(err)
+	}
+	rrs := make([]dns.RR, 0, len(recs))
+	for _, txt := range recs {
+		rrs = append(rrs, &dns.TXT{
+			Hdr: recordHeader(fqdn, dns.TypeTXT, ttl),
+			Txt: chunkTXT(txt),
+		})
+	}
+	return rrs, dns.RcodeSuccess
+}
+
+func lookupNS(ctx context.Context, r RecordResolver, name, fqdn string, ttl uint32) ([]dns.RR, int) {
+	recs, err := r.LookupNS(ctx, name)
+	if err != nil {
+		return nil, rcodeForRecordError(err)
+	}
+	rrs := make([]dns.RR, 0, len(recs))
+	for _, ns := range recs {
+		rrs = append(rrs, &dns.NS{
+			Hdr: recordHeader(fqdn, dns.TypeNS, ttl),
+			Ns:  dns.Fqdn(ns.Host),
+		})
+	}
+	return rrs, dns.RcodeSuccess
+}
+
+func lookupSRV(ctx context.Context, r RecordResolver, name, fqdn string, ttl uint32) ([]dns.RR, int) {
+	_, recs, err := r.LookupSRV(ctx, "", "", name)
+	if err != nil {
+		return nil, rcodeForRecordError(err)
+	}
+	rrs := make([]dns.RR, 0, len(recs))
+	for _, srv := range recs {
+		rrs = append(rrs, &dns.SRV{
+			Hdr:      recordHeader(fqdn, dns.TypeSRV, ttl),
+			Priority: srv.Priority,
+			Weight:   srv.Weight,
+			Port:     srv.Port,
+			Target:   dns.Fqdn(srv.Target),
+		})
+	}
+	return rrs, dns.RcodeSuccess
+}
+
+func lookupCNAME(ctx context.Context, r RecordResolver, name, fqdn string, ttl uint32) ([]dns.RR, int) {
+	cname, err := r.LookupCNAME(ctx, name)
+	if err != nil {
+		return nil, rcodeForRecordError(err)
+	}
+	// LookupCNAME returns the queried name itself when the name resolves but
+	// has no CNAME record; that is a NODATA result, not a CNAME.
+	if strings.EqualFold(dns.Fqdn(cname), fqdn) {
+		return nil, dns.RcodeSuccess
+	}
+	return []dns.RR{&dns.CNAME{
+		Hdr:    recordHeader(fqdn, dns.TypeCNAME, ttl),
+		Target: dns.Fqdn(cname),
+	}}, dns.RcodeSuccess
+}
+
+func lookupPTR(ctx context.Context, r RecordResolver, name, fqdn string, ttl uint32) ([]dns.RR, int) {
+	addr, ok := ptrQueryAddr(name)
+	if !ok {
+		return nil, dns.RcodeSuccess
+	}
+	names, err := r.LookupAddr(ctx, addr)
+	if err != nil {
+		return nil, rcodeForRecordError(err)
+	}
+	rrs := make([]dns.RR, 0, len(names))
+	for _, n := range names {
+		rrs = append(rrs, &dns.PTR{
+			Hdr: recordHeader(fqdn, dns.TypePTR, ttl),
+			Ptr: dns.Fqdn(n),
+		})
+	}
+	return rrs, dns.RcodeSuccess
+}
+
+// ptrQueryAddr converts a reverse-DNS query name (in-addr.arpa or ip6.arpa)
+// into the address string expected by net.Resolver.LookupAddr. It reports false
+// when the name is not a well-formed reverse name.
+func ptrQueryAddr(qname string) (string, bool) {
+	name := strings.TrimSuffix(strings.ToLower(dns.Fqdn(qname)), ".")
+
+	switch {
+	case strings.HasSuffix(name, ".in-addr.arpa"):
+		return parseInAddrArpa(strings.TrimSuffix(name, ".in-addr.arpa"))
+	case strings.HasSuffix(name, ".ip6.arpa"):
+		return parseIP6Arpa(strings.TrimSuffix(name, ".ip6.arpa"))
+	default:
+		return "", false
+	}
+}
+
+// parseInAddrArpa turns the label portion of an in-addr.arpa name into an IPv4
+// address string, reporting false when it is not a well-formed reverse name.
+func parseInAddrArpa(labelPart string) (string, bool) {
+	labels := strings.Split(labelPart, ".")
+	if len(labels) != 4 {
+		return "", false
+	}
+	slices.Reverse(labels)
+	addr, err := netip.ParseAddr(strings.Join(labels, "."))
+	if err != nil || !addr.Is4() {
+		return "", false
+	}
+	return addr.String(), true
+}
+
+// parseIP6Arpa turns the nibble portion of an ip6.arpa name into an IPv6
+// address string, reporting false when it is not a well-formed reverse name.
+func parseIP6Arpa(nibblePart string) (string, bool) {
+	nibbles := strings.Split(nibblePart, ".")
+	if len(nibbles) != 32 {
+		return "", false
+	}
+	slices.Reverse(nibbles)
+	var sb strings.Builder
+	for i, n := range nibbles {
+		if i > 0 && i%4 == 0 {
+			sb.WriteByte(':')
+		}
+		sb.WriteString(n)
+	}
+	addr, err := netip.ParseAddr(sb.String())
+	if err != nil || !addr.Is6() {
+		return "", false
+	}
+	return addr.String(), true
+}
+
+// rcodeForRecordError maps a non-address lookup error to a DNS rcode. A
+// not-found result becomes NODATA rather than NXDOMAIN: net.DNSError.IsNotFound
+// does not distinguish a missing name from a name that exists only with records
+// of other types, so the name cannot be proven absent and must not be poisoned.
+func rcodeForRecordError(err error) int {
+	var dnsErr *net.DNSError
+	if errors.As(err, &dnsErr) && dnsErr.IsNotFound {
+		return dns.RcodeSuccess
+	}
+	return dns.RcodeServerFailure
+}
+
+// chunkTXT splits a TXT string into character-strings no longer than 255 bytes
+// so the record can be packed. The chunks form one TXT resource record.
+func chunkTXT(s string) []string {
+	const maxLen = 255
+	if len(s) <= maxLen {
+		return []string{s}
+	}
+
+	var chunks []string
+	for len(s) > maxLen {
+		chunks = append(chunks, s[:maxLen])
+		s = s[maxLen:]
+	}
+	if len(s) > 0 {
+		chunks = append(chunks, s)
+	}
+	return chunks
+}
+
 // FormatAnswers formats DNS resource records for logging.
 func FormatAnswers(answers []dns.RR) string {
 	if len(answers) == 0 {
@@ -195,3 +435,35 @@ func FormatAnswers(answers []dns.RR) string {
 	}
 	return "[" + strings.Join(parts, ", ") + "]"
 }
+
+// StripOPT removes any OPT pseudo-RRs from the message's Extra section. Per
+// RFC 6891 a responder must not include an OPT RR toward a client that did not
+// advertise EDNS0.
+func StripOPT(msg *dns.Msg) {
+	if len(msg.Extra) == 0 {
+		return
+	}
+	out := msg.Extra[:0]
+	for _, rr := range msg.Extra {
+		if _, ok := rr.(*dns.OPT); ok {
+			continue
+		}
+		out = append(out, rr)
+	}
+	msg.Extra = out
+}
+
+// ExtractEDE returns the first Extended DNS Error (RFC 8914) option carried in
+// the message, if present.
+func ExtractEDE(msg *dns.Msg) (*dns.EDNS0_EDE, bool) {
+	opt := msg.IsEdns0()
+	if opt == nil {
+		return nil, false
+	}
+	for _, o := range opt.Option {
+		if ede, ok := o.(*dns.EDNS0_EDE); ok {
+			return ede, true
+		}
+	}
+	return nil, false
+}

client/internal/dns/resutil/resolve_test.go

@@ -0,0 +1,320 @@
+package resutil
+
+import (
+	"context"
+	"errors"
+	"net"
+	"net/netip"
+	"strings"
+	"testing"
+
+	"github.com/miekg/dns"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+type mockResolver struct {
+	// results maps network ("ip4"/"ip6") to the lookup outcome.
+	results map[string]mockLookup
+}
+
+type mockLookup struct {
+	ips []netip.Addr
+	err error
+}
+
+func (m *mockResolver) LookupNetIP(_ context.Context, network, _ string) ([]netip.Addr, error) {
+	res, ok := m.results[network]
+	if !ok {
+		return nil, errors.New("unexpected network: " + network)
+	}
+	return res.ips, res.err
+}
+
+func TestLookupIP_Success(t *testing.T) {
+	r := &mockResolver{results: map[string]mockLookup{
+		"ip4": {ips: []netip.Addr{netip.MustParseAddr("::ffff:192.0.2.1")}},
+	}}
+
+	result := LookupIP(context.Background(), r, "ip4", "example.com.", dns.TypeA)
+
+	assert.Equal(t, dns.RcodeSuccess, result.Rcode, "successful lookup should return NOERROR")
+	require.Len(t, result.IPs, 1, "should return the resolved address")
+	assert.Equal(t, netip.MustParseAddr("192.0.2.1"), result.IPs[0], "v4-mapped address should be unmapped")
+}
+
+func TestLookupIP_NoSuitableAddress(t *testing.T) {
+	// The net package returns this AddrError when the host resolves but has
+	// no addresses of the requested family (e.g. AAAA query for a v4-only
+	// hosts file entry). The domain exists, so this is NODATA, not SERVFAIL.
+	r := &mockResolver{results: map[string]mockLookup{
+		"ip6": {err: &net.AddrError{Err: "no suitable address found", Addr: "example.com."}},
+	}}
+
+	result := LookupIP(context.Background(), r, "ip6", "example.com.", dns.TypeAAAA)
+
+	assert.Equal(t, dns.RcodeSuccess, result.Rcode, "no suitable address should map to NODATA")
+	assert.Empty(t, result.IPs, "NODATA response should carry no addresses")
+}
+
+// TestErrNoSuitableAddressMatchesNetPackage pins our copy of the error string
+// to what the net package actually emits. A literal IP of the wrong family
+// takes the same filterAddrList path as a resolved hostname, without network
+// access.
+func TestErrNoSuitableAddressMatchesNetPackage(t *testing.T) {
+	_, err := (&net.Resolver{}).LookupNetIP(context.Background(), "ip6", "192.0.2.1")
+	require.Error(t, err)
+
+	var addrErr *net.AddrError
+	require.ErrorAs(t, err, &addrErr, "wrong-family lookup should return AddrError")
+	assert.Equal(t, errNoSuitableAddress, addrErr.Err, "net package error string should match our constant")
+}
+
+func TestLookupIP_OtherAddrError(t *testing.T) {
+	r := &mockResolver{results: map[string]mockLookup{
+		"ip4": {err: &net.AddrError{Err: "some other address problem", Addr: "example.com."}},
+	}}
+
+	result := LookupIP(context.Background(), r, "ip4", "example.com.", dns.TypeA)
+
+	assert.Equal(t, dns.RcodeServerFailure, result.Rcode, "unrecognized AddrError should map to SERVFAIL")
+}
+
+func TestLookupIP_NotFoundNXDomain(t *testing.T) {
+	r := &mockResolver{results: map[string]mockLookup{
+		"ip4": {err: &net.DNSError{Err: "no such host", Name: "example.com.", IsNotFound: true}},
+		"ip6": {err: &net.DNSError{Err: "no such host", Name: "example.com.", IsNotFound: true}},
+	}}
+
+	result := LookupIP(context.Background(), r, "ip4", "example.com.", dns.TypeA)
+
+	assert.Equal(t, dns.RcodeNameError, result.Rcode, "not found for both families should map to NXDOMAIN")
+}
+
+func TestLookupIP_NotFoundNoData(t *testing.T) {
+	r := &mockResolver{results: map[string]mockLookup{
+		"ip6": {err: &net.DNSError{Err: "no such host", Name: "example.com.", IsNotFound: true}},
+		"ip4": {ips: []netip.Addr{netip.MustParseAddr("192.0.2.1")}},
+	}}
+
+	result := LookupIP(context.Background(), r, "ip6", "example.com.", dns.TypeAAAA)
+
+	assert.Equal(t, dns.RcodeSuccess, result.Rcode, "not found with the other family present should map to NODATA")
+}
+
+func TestLookupIP_GenericError(t *testing.T) {
+	r := &mockResolver{results: map[string]mockLookup{
+		"ip4": {err: errors.New("connection refused")},
+	}}
+
+	result := LookupIP(context.Background(), r, "ip4", "example.com.", dns.TypeA)
+
+	assert.Equal(t, dns.RcodeServerFailure, result.Rcode, "generic error should map to SERVFAIL")
+}
+
+func TestLookupIP_DNSErrorNotIsNotFound(t *testing.T) {
+	r := &mockResolver{results: map[string]mockLookup{
+		"ip4": {err: &net.DNSError{Err: "server misbehaving", Name: "example.com.", IsTemporary: true}},
+	}}
+
+	result := LookupIP(context.Background(), r, "ip4", "example.com.", dns.TypeA)
+
+	assert.Equal(t, dns.RcodeServerFailure, result.Rcode, "upstream failure should map to SERVFAIL")
+}
+
+func TestPtrQueryAddr(t *testing.T) {
+	tests := []struct {
+		name   string
+		qname  string
+		want   string
+		wantOK bool
+	}{
+		{name: "ipv4", qname: "4.3.2.1.in-addr.arpa.", want: "1.2.3.4", wantOK: true},
+		{name: "ipv4 no trailing dot", qname: "1.0.0.127.in-addr.arpa", want: "127.0.0.1", wantOK: true},
+		{
+			name:   "ipv6",
+			qname:  "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.",
+			want:   "2001:db8::1",
+			wantOK: true,
+		},
+		{name: "ipv4 wrong label count", qname: "2.1.in-addr.arpa.", wantOK: false},
+		{name: "ipv6 wrong nibble count", qname: "1.0.ip6.arpa.", wantOK: false},
+		{name: "not a reverse name", qname: "example.com.", wantOK: false},
+		{name: "ipv4 bad octet", qname: "4.3.2.999.in-addr.arpa.", wantOK: false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, ok := ptrQueryAddr(tt.qname)
+			assert.Equal(t, tt.wantOK, ok, "parse success mismatch")
+			if tt.wantOK {
+				assert.Equal(t, tt.want, got, "parsed address mismatch")
+			}
+		})
+	}
+}
+
+type mockRecordResolver struct {
+	mx    []*net.MX
+	txt   []string
+	ns    []*net.NS
+	srv   []*net.SRV
+	cname string
+	ptr   []string
+	err   error
+}
+
+func (m *mockRecordResolver) LookupMX(context.Context, string) ([]*net.MX, error) {
+	return m.mx, m.err
+}
+func (m *mockRecordResolver) LookupTXT(context.Context, string) ([]string, error) {
+	return m.txt, m.err
+}
+func (m *mockRecordResolver) LookupNS(context.Context, string) ([]*net.NS, error) {
+	return m.ns, m.err
+}
+func (m *mockRecordResolver) LookupSRV(context.Context, string, string, string) (string, []*net.SRV, error) {
+	return "", m.srv, m.err
+}
+func (m *mockRecordResolver) LookupCNAME(context.Context, string) (string, error) {
+	return m.cname, m.err
+}
+func (m *mockRecordResolver) LookupAddr(context.Context, string) ([]string, error) {
+	return m.ptr, m.err
+}
+
+func TestLookupRecords(t *testing.T) {
+	notFound := &net.DNSError{IsNotFound: true, Name: "example.com."}
+
+	t.Run("MX success", func(t *testing.T) {
+		r := &mockRecordResolver{mx: []*net.MX{{Host: "mail.example.com.", Pref: 10}}}
+		rrs, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeMX, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		require.Len(t, rrs, 1)
+		assert.Equal(t, "mail.example.com.", rrs[0].(*dns.MX).Mx)
+	})
+
+	t.Run("TXT short string is one character-string", func(t *testing.T) {
+		r := &mockRecordResolver{txt: []string{"v=spf1 -all"}}
+		rrs, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeTXT, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		require.Len(t, rrs, 1)
+		assert.Equal(t, []string{"v=spf1 -all"}, rrs[0].(*dns.TXT).Txt)
+	})
+
+	t.Run("TXT chunks long strings", func(t *testing.T) {
+		long := strings.Repeat("a", 300)
+		r := &mockRecordResolver{txt: []string{long}}
+		rrs, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeTXT, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		require.Len(t, rrs, 1)
+		txt := rrs[0].(*dns.TXT).Txt
+		require.Len(t, txt, 2, "300-byte string should split into two character-strings")
+		assert.Equal(t, 255, len(txt[0]))
+		assert.Equal(t, 45, len(txt[1]))
+	})
+
+	t.Run("NS success", func(t *testing.T) {
+		r := &mockRecordResolver{ns: []*net.NS{{Host: "ns1.example.com."}}}
+		rrs, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeNS, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		require.Len(t, rrs, 1)
+		assert.Equal(t, "ns1.example.com.", rrs[0].(*dns.NS).Ns)
+	})
+
+	t.Run("SRV success", func(t *testing.T) {
+		r := &mockRecordResolver{srv: []*net.SRV{{Target: "sip.example.com.", Port: 5060}}}
+		rrs, rcode := LookupRecords(context.Background(), r, "_sip._tcp.example.com.", dns.TypeSRV, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		require.Len(t, rrs, 1)
+		assert.Equal(t, uint16(5060), rrs[0].(*dns.SRV).Port)
+	})
+
+	t.Run("CNAME success", func(t *testing.T) {
+		r := &mockRecordResolver{cname: "target.example.com."}
+		rrs, rcode := LookupRecords(context.Background(), r, "www.example.com.", dns.TypeCNAME, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		require.Len(t, rrs, 1)
+		assert.Equal(t, "target.example.com.", rrs[0].(*dns.CNAME).Target)
+	})
+
+	t.Run("CNAME equal to name is NODATA", func(t *testing.T) {
+		r := &mockRecordResolver{cname: "example.com."}
+		rrs, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeCNAME, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		assert.Empty(t, rrs, "self-referential CNAME is NODATA")
+	})
+
+	t.Run("PTR success", func(t *testing.T) {
+		r := &mockRecordResolver{ptr: []string{"host.example.com."}}
+		rrs, rcode := LookupRecords(context.Background(), r, "4.3.2.1.in-addr.arpa.", dns.TypePTR, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		require.Len(t, rrs, 1)
+		assert.Equal(t, "host.example.com.", rrs[0].(*dns.PTR).Ptr)
+	})
+
+	t.Run("PTR malformed name is NODATA", func(t *testing.T) {
+		r := &mockRecordResolver{}
+		rrs, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypePTR, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		assert.Empty(t, rrs)
+	})
+
+	t.Run("not found is NODATA never NXDOMAIN", func(t *testing.T) {
+		r := &mockRecordResolver{err: notFound}
+		_, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeMX, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode, "missing record must not poison the name")
+	})
+
+	t.Run("server failure maps to SERVFAIL", func(t *testing.T) {
+		r := &mockRecordResolver{err: &net.DNSError{Err: "server misbehaving", IsTemporary: true}}
+		_, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeMX, 300)
+		assert.Equal(t, dns.RcodeServerFailure, rcode)
+	})
+
+	t.Run("unsupported type is NODATA", func(t *testing.T) {
+		r := &mockRecordResolver{}
+		rrs, rcode := LookupRecords(context.Background(), r, "example.com.", dns.TypeCAA, 300)
+		assert.Equal(t, dns.RcodeSuccess, rcode)
+		assert.Empty(t, rrs)
+	})
+}
+
+func TestStripOPT(t *testing.T) {
+	rm := &dns.Msg{
+		Extra: []dns.RR{
+			&dns.OPT{Hdr: dns.RR_Header{Name: ".", Rrtype: dns.TypeOPT}},
+			&dns.A{Hdr: dns.RR_Header{Name: "x.", Rrtype: dns.TypeA}, A: net.IPv4(1, 2, 3, 4)},
+		},
+	}
+	StripOPT(rm)
+	assert.Len(t, rm.Extra, 1, "OPT should be removed, A kept")
+	_, isOPT := rm.Extra[0].(*dns.OPT)
+	assert.False(t, isOPT, "remaining record must not be OPT")
+}
+
+func TestExtractEDE(t *testing.T) {
+	t.Run("no edns", func(t *testing.T) {
+		_, ok := ExtractEDE(&dns.Msg{})
+		assert.False(t, ok, "message without OPT has no EDE")
+	})
+
+	t.Run("edns without ede", func(t *testing.T) {
+		rm := &dns.Msg{}
+		rm.SetEdns0(4096, false)
+		_, ok := ExtractEDE(rm)
+		assert.False(t, ok, "OPT without EDE option returns false")
+	})
+
+	t.Run("with ede", func(t *testing.T) {
+		rm := &dns.Msg{}
+		opt := &dns.OPT{Hdr: dns.RR_Header{Name: ".", Rrtype: dns.TypeOPT}}
+		opt.Option = append(opt.Option, &dns.EDNS0_EDE{InfoCode: 49152, ExtraText: "upstream timeout"})
+		rm.Extra = append(rm.Extra, opt)
+
+		ede, ok := ExtractEDE(rm)
+		assert.True(t, ok, "EDE option should be found")
+		assert.Equal(t, uint16(49152), ede.InfoCode)
+		assert.Equal(t, "upstream timeout", ede.ExtraText)
+	})
+}

client/internal/dns/server.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net/netip"
 	"net/url"
+	"os"
 	"slices"
 	"strings"
 	"sync"
@@ -38,11 +39,15 @@ const (
 	// defaultWarningDelayBase is the starting grace window before a
 	// "Nameserver group unreachable" event fires for a group that's
 	// never been healthy and only has overlay upstreams with no
-	// Connected peer. Per-server and overridable; see warningDelayFor.
-	defaultWarningDelayBase = 30 * time.Second
+	// Connected peer. Per-server and overridable via envWarningDelay;
+	// see warningDelay.
+	defaultWarningDelayBase = 60 * time.Second
 	// warningDelayBonusCap caps the route-count bonus added to the
-	// base grace window. See warningDelayFor.
+	// base grace window. See warningDelay.
 	warningDelayBonusCap = 30 * time.Second
+	// envWarningDelay overrides defaultWarningDelayBase with a Go duration
+	// string (e.g. "90s", "2m"). Invalid or non-positive values are ignored.
+	envWarningDelay = "NB_DNS_HEALTH_WARNING_DELAY"
 )
 
 // errNoUsableNameservers signals that a merged-domain group has no usable
@@ -77,6 +82,7 @@ type Server interface {
 	PopulateManagementDomain(mgmtURL *url.URL) error
 	SetRouteSources(selected, active func() route.HAMap)
 	SetFirewall(Firewall)
+	SetPeerActivator(local.PeerActivator)
 }
 
 type nsGroupsByDomain struct {
@@ -135,7 +141,7 @@ type DefaultServer struct {
 	disableSys         bool
 	mux                sync.Mutex
 	service            service
-	dnsMuxMap          registeredHandlerMap
+	dnsMuxHandlers     []handlerWrapper
 	localResolver      *local.Resolver
 	wgInterface        WGIface
 	hostManager        hostManager
@@ -199,8 +205,6 @@ type handlerWrapper struct {
 	priority int
 }
 
-type registeredHandlerMap map[types.HandlerID]handlerWrapper
-
 // DefaultServerConfig holds configuration parameters for NewDefaultServer
 type DefaultServerConfig struct {
 	WgInterface    WGIface
@@ -248,7 +252,7 @@ func NewDefaultServerPermanentUpstream(
 	ds.hostsDNSHolder.set(hostsDnsList)
 	ds.permanent = true
 	ds.currentConfig = dnsConfigToHostDNSConfig(config, ds.service.RuntimeIP(), ds.service.RuntimePort())
-	ds.searchDomainNotifier = newNotifier(ds.SearchDomains())
+	ds.searchDomainNotifier = newNotifier(ds.searchDomains())
 	ds.searchDomainNotifier.setListener(listener)
 	setServerDns(ds)
 	return ds
@@ -289,7 +293,6 @@ func newDefaultServer(
 		service:           dnsService,
 		handlerChain:      handlerChain,
 		extraDomains:      make(map[domain.Domain]int),
-		dnsMuxMap:         make(registeredHandlerMap),
 		localResolver:     local.NewResolver(),
 		wgInterface:       wgInterface,
 		statusRecorder:    statusRecorder,
@@ -298,7 +301,7 @@ func newDefaultServer(
 		hostManager:       &noopHostConfigurator{},
 		mgmtCacheResolver: mgmtCacheResolver,
 		currentConfigHash: ^uint64(0), // Initialize to max uint64 to ensure first config is always applied
-		warningDelayBase:  defaultWarningDelayBase,
+		warningDelayBase:  warningDelayBaseFromEnv(),
 		healthRefresh:     make(chan struct{}, 1),
 	}
 	// Wire the local resolver against the peer status recorder so it can
@@ -328,7 +331,7 @@ func (s *DefaultServer) SetRouteSources(selected, active func() route.HAMap) {
 	type routeSettable interface {
 		setSelectedRoutes(func() route.HAMap)
 	}
-	for _, entry := range s.dnsMuxMap {
+	for _, entry := range s.dnsMuxHandlers {
 		if h, ok := entry.handler.(routeSettable); ok {
 			h.setSelectedRoutes(selected)
 		}
@@ -489,6 +492,13 @@ func (s *DefaultServer) SetFirewall(fw Firewall) {
 	}
 }
 
+// SetPeerActivator wires the DNS-time lazy-connection warm-up on the local
+// resolver. Injected after the connection manager exists (it does not at
+// DNS-server construction time). Pass nil to disable.
+func (s *DefaultServer) SetPeerActivator(a local.PeerActivator) {
+	s.localResolver.SetPeerActivator(a)
+}
+
 // Stop stops the server
 func (s *DefaultServer) Stop() {
 	s.ctxCancel()
@@ -592,6 +602,12 @@ func (s *DefaultServer) UpdateDNSServer(serial uint64, update nbdns.Config) erro
 }
 
 func (s *DefaultServer) SearchDomains() []string {
+	s.mux.Lock()
+	defer s.mux.Unlock()
+	return s.searchDomains()
+}
+
+func (s *DefaultServer) searchDomains() []string {
 	var searchDomains []string
 
 	for _, dConf := range s.currentConfig.Domains {
@@ -676,7 +692,7 @@ func (s *DefaultServer) applyConfiguration(update nbdns.Config) error {
 	}()
 
 	if s.searchDomainNotifier != nil {
-		s.searchDomainNotifier.onNewSearchDomains(s.SearchDomains())
+		s.searchDomainNotifier.onNewSearchDomains(s.searchDomains())
 	}
 
 	s.updateNSGroupStates(update.NameServerGroups)
@@ -978,19 +994,23 @@ func (s *DefaultServer) usableNameServers(nameServers []nbdns.NameServer) []neti
 
 func (s *DefaultServer) updateMux(muxUpdates []handlerWrapper) {
 	// this will introduce a short period of time when the server is not able to handle DNS requests
-	for _, existing := range s.dnsMuxMap {
+	for _, existing := range s.dnsMuxHandlers {
 		s.deregisterHandler([]string{existing.domain}, existing.priority)
-		existing.handler.Stop()
+		// The local resolver is a persistent singleton shared by every custom
+		// zone and reused across config updates. Its chain registrations are
+		// per-config and must be deregistered, but Stop() cancels its lookup
+		// context (breaking external CNAME-target resolution) and clears its
+		// records, so it must not be torn down here.
+		if existing.handler != s.localResolver {
+			existing.handler.Stop()
+		}
 	}
 
-	muxUpdateMap := make(registeredHandlerMap)
-
 	for _, update := range muxUpdates {
 		s.registerHandler([]string{update.domain}, update.handler, update.priority)
-		muxUpdateMap[update.handler.ID()] = update
 	}
 
-	s.dnsMuxMap = muxUpdateMap
+	s.dnsMuxHandlers = muxUpdates
 }
 
 // updateNSGroupStates records the new group set and pokes the refresher.
@@ -1154,6 +1174,26 @@ func (s *DefaultServer) projectUnhealthy(p *nsGroupProj, servers []netip.AddrPor
 	return false
 }
 
+// warningDelayBaseFromEnv returns the base grace window, honoring
+// envWarningDelay when it holds a valid positive Go duration. Invalid or
+// non-positive values fall back to defaultWarningDelayBase.
+func warningDelayBaseFromEnv() time.Duration {
+	val := os.Getenv(envWarningDelay)
+	if val == "" {
+		return defaultWarningDelayBase
+	}
+	d, err := time.ParseDuration(val)
+	if err != nil {
+		log.Warnf("invalid %s value %q, using default %v: %v", envWarningDelay, val, defaultWarningDelayBase, err)
+		return defaultWarningDelayBase
+	}
+	if d <= 0 {
+		log.Warnf("%s must be positive, got %v, using default %v", envWarningDelay, d, defaultWarningDelayBase)
+		return defaultWarningDelayBase
+	}
+	return d
+}
+
 // warningDelay returns the grace window for the given selected-route
 // count. Scales gently: +1s per 100 routes, capped by
 // warningDelayBonusCap. Parallel handshakes mean handshake time grows
@@ -1204,7 +1244,7 @@ func (s *DefaultServer) groupHasImmediateUpstream(servers []netip.AddrPort, snap
 // in more than one handler.
 func (s *DefaultServer) collectUpstreamHealth() map[netip.AddrPort]UpstreamHealth {
 	merged := make(map[netip.AddrPort]UpstreamHealth)
-	for _, entry := range s.dnsMuxMap {
+	for _, entry := range s.dnsMuxHandlers {
 		reporter, ok := entry.handler.(upstreamHealthReporter)
 		if !ok {
 			continue
@@ -1409,11 +1449,11 @@ type localPeerConnectivity struct {
 
 // IsConnectedByIP looks the IP up in the peerstore and surfaces both
 // the known and connected bits. Used by Resolver.filterDisconnectedPeerAnswers.
-func (l localPeerConnectivity) IsConnectedByIP(ip string) (known, connected bool) {
+func (l localPeerConnectivity) IsConnectedByIP(ip netip.Addr) (known, connected bool) {
 	if l.status == nil {
 		return false, false
 	}
-	state, ok := l.status.PeerStateByIP(ip)
+	state, ok := l.status.PeerStateByIP(ip.String())
 	if !ok {
 		return false, false
 	}

client/internal/dns/server_privileged_test.go

@@ -0,0 +1,485 @@
+//go:build privileged
+
+package dns
+
+import (
+	"context"
+	"fmt"
+	"net/netip"
+	"os"
+	"testing"
+
+	"go.uber.org/mock/gomock"
+	"github.com/miekg/dns"
+	"github.com/stretchr/testify/assert"
+	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
+
+	"github.com/netbirdio/netbird/client/iface"
+	pfmock "github.com/netbirdio/netbird/client/iface/mocks"
+	"github.com/netbirdio/netbird/client/iface/wgaddr"
+	"github.com/netbirdio/netbird/client/internal/dns/local"
+	"github.com/netbirdio/netbird/client/internal/dns/test"
+	"github.com/netbirdio/netbird/client/internal/peer"
+	"github.com/netbirdio/netbird/client/internal/stdnet"
+	nbdns "github.com/netbirdio/netbird/dns"
+)
+
+func TestUpdateDNSServer(t *testing.T) {
+
+	nameServers := []nbdns.NameServer{
+		{
+			IP:     netip.MustParseAddr("8.8.8.8"),
+			NSType: nbdns.UDPNameServerType,
+			Port:   53,
+		},
+		{
+			IP:     netip.MustParseAddr("8.8.4.4"),
+			NSType: nbdns.UDPNameServerType,
+			Port:   53,
+		},
+	}
+
+	testCases := []struct {
+		name                string
+		initUpstreamMap     []handlerWrapper
+		initLocalZones      []nbdns.CustomZone
+		initSerial          uint64
+		inputSerial         uint64
+		inputUpdate         nbdns.Config
+		shouldFail          bool
+		expectedUpstreamMap []handlerWrapper
+		expectedLocalQs     []dns.Question
+	}{
+		{
+			name:            "Initial Config Should Succeed",
+			initUpstreamMap: nil,
+			initSerial:      0,
+			inputSerial:     1,
+			inputUpdate: nbdns.Config{
+				ServiceEnable: true,
+				CustomZones: []nbdns.CustomZone{
+					{
+						Domain:  "netbird.cloud",
+						Records: zoneRecords,
+					},
+				},
+				NameServerGroups: []*nbdns.NameServerGroup{
+					{
+						Domains:     []string{"netbird.io"},
+						NameServers: nameServers,
+					},
+					{
+						NameServers: nameServers,
+						Primary:     true,
+					},
+				},
+			},
+			expectedUpstreamMap: []handlerWrapper{
+				{
+					domain:   "netbird.io",
+					priority: PriorityUpstream,
+				},
+				{
+					domain:   "netbird.cloud",
+					priority: PriorityLocal,
+				},
+				{
+					domain:   nbdns.RootZone,
+					priority: PriorityDefault,
+				},
+			},
+			expectedLocalQs: []dns.Question{{Name: "peera.netbird.cloud.", Qtype: dns.TypeA, Qclass: dns.ClassINET}},
+		},
+		{
+			name:           "New Config Should Succeed",
+			initLocalZones: []nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}},
+			initUpstreamMap: []handlerWrapper{
+				{
+					domain:   "netbird.cloud",
+					handler:  &mockHandler{},
+					priority: PriorityUpstream,
+				},
+			},
+			initSerial:  0,
+			inputSerial: 1,
+			inputUpdate: nbdns.Config{
+				ServiceEnable: true,
+				CustomZones: []nbdns.CustomZone{
+					{
+						Domain:  "netbird.cloud",
+						Records: zoneRecords,
+					},
+				},
+				NameServerGroups: []*nbdns.NameServerGroup{
+					{
+						Domains:     []string{"netbird.io"},
+						NameServers: nameServers,
+					},
+				},
+			},
+			expectedUpstreamMap: []handlerWrapper{
+				{
+					domain:   "netbird.io",
+					priority: PriorityUpstream,
+				},
+				{
+					domain:   "netbird.cloud",
+					priority: PriorityLocal,
+				},
+			},
+			expectedLocalQs: []dns.Question{{Name: zoneRecords[0].Name, Qtype: 1, Qclass: 1}},
+		},
+		{
+			name:            "Smaller Config Serial Should Be Skipped",
+			initLocalZones:  []nbdns.CustomZone{},
+			initUpstreamMap: nil,
+			initSerial:      2,
+			inputSerial:     1,
+			shouldFail:      true,
+		},
+		{
+			name:            "Empty NS Group Domain Or Not Primary Element Should Fail",
+			initLocalZones:  []nbdns.CustomZone{},
+			initUpstreamMap: nil,
+			initSerial:      0,
+			inputSerial:     1,
+			inputUpdate: nbdns.Config{
+				ServiceEnable: true,
+				CustomZones: []nbdns.CustomZone{
+					{
+						Domain:  "netbird.cloud",
+						Records: zoneRecords,
+					},
+				},
+				NameServerGroups: []*nbdns.NameServerGroup{
+					{
+						NameServers: nameServers,
+					},
+				},
+			},
+			shouldFail: true,
+		},
+		{
+			name:            "Invalid NS Group Nameservers list Should Fail",
+			initLocalZones:  []nbdns.CustomZone{},
+			initUpstreamMap: nil,
+			initSerial:      0,
+			inputSerial:     1,
+			inputUpdate: nbdns.Config{
+				ServiceEnable: true,
+				CustomZones: []nbdns.CustomZone{
+					{
+						Domain:  "netbird.cloud",
+						Records: zoneRecords,
+					},
+				},
+				NameServerGroups: []*nbdns.NameServerGroup{
+					{
+						NameServers: nameServers,
+					},
+				},
+			},
+			shouldFail: true,
+		},
+		{
+			name:            "Invalid Custom Zone Records list Should Skip",
+			initLocalZones:  []nbdns.CustomZone{},
+			initUpstreamMap: nil,
+			initSerial:      0,
+			inputSerial:     1,
+			inputUpdate: nbdns.Config{
+				ServiceEnable: true,
+				CustomZones: []nbdns.CustomZone{
+					{
+						Domain: "netbird.cloud",
+					},
+				},
+				NameServerGroups: []*nbdns.NameServerGroup{
+					{
+						NameServers: nameServers,
+						Primary:     true,
+					},
+				},
+			},
+			expectedUpstreamMap: []handlerWrapper{{
+				domain:   ".",
+				priority: PriorityDefault,
+			}},
+		},
+		{
+			name:           "Empty Config Should Succeed and Clean Maps",
+			initLocalZones: []nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: int(dns.TypeA), Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}},
+			initUpstreamMap: []handlerWrapper{
+				{
+					domain:   zoneRecords[0].Name,
+					handler:  &mockHandler{},
+					priority: PriorityUpstream,
+				},
+			},
+			initSerial:          0,
+			inputSerial:         1,
+			inputUpdate:         nbdns.Config{ServiceEnable: true},
+			expectedUpstreamMap: nil,
+			expectedLocalQs:     []dns.Question{},
+		},
+		{
+			name:           "Disabled Service Should clean map",
+			initLocalZones: []nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: int(dns.TypeA), Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}},
+			initUpstreamMap: []handlerWrapper{
+				{
+					domain:   zoneRecords[0].Name,
+					handler:  &mockHandler{},
+					priority: PriorityUpstream,
+				},
+			},
+			initSerial:          0,
+			inputSerial:         1,
+			inputUpdate:         nbdns.Config{ServiceEnable: false},
+			expectedUpstreamMap: nil,
+			expectedLocalQs:     []dns.Question{},
+		},
+	}
+
+	for n, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			privKey, _ := wgtypes.GenerateKey()
+			newNet, err := stdnet.NewNet(context.Background(), nil)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			opts := iface.WGIFaceOpts{
+				IFaceName:    fmt.Sprintf("utun230%d", n),
+				Address:      wgaddr.MustParseWGAddress(fmt.Sprintf("100.66.100.%d/32", n+1)),
+				WGPort:       33100,
+				WGPrivKey:    privKey.String(),
+				MTU:          iface.DefaultMTU,
+				TransportNet: newNet,
+			}
+
+			wgIface, err := iface.NewWGIFace(opts)
+			if err != nil {
+				t.Fatal(err)
+			}
+			err = wgIface.Create()
+			if err != nil {
+				t.Fatal(err)
+			}
+			defer func() {
+				err = wgIface.Close()
+				if err != nil {
+					t.Log(err)
+				}
+			}()
+			dnsServer, err := NewDefaultServer(context.Background(), DefaultServerConfig{
+				WgInterface:    wgIface,
+				CustomAddress:  "",
+				StatusRecorder: peer.NewRecorder("mgm"),
+				StateManager:   nil,
+				DisableSys:     false,
+			})
+			if err != nil {
+				t.Fatal(err)
+			}
+			err = dnsServer.Initialize()
+			if err != nil {
+				t.Fatal(err)
+			}
+			defer func() {
+				err = dnsServer.hostManager.restoreHostDNS()
+				if err != nil {
+					t.Log(err)
+				}
+			}()
+
+			dnsServer.dnsMuxHandlers = testCase.initUpstreamMap
+			dnsServer.localResolver.Update(testCase.initLocalZones)
+			dnsServer.updateSerial = testCase.initSerial
+
+			err = dnsServer.UpdateDNSServer(testCase.inputSerial, testCase.inputUpdate)
+			if err != nil {
+				if testCase.shouldFail {
+					return
+				}
+				t.Fatalf("update dns server should not fail, got error: %v", err)
+			}
+
+			if len(dnsServer.dnsMuxHandlers) != len(testCase.expectedUpstreamMap) {
+				t.Fatalf("update upstream failed, map size is different than expected, want %d, got %d", len(testCase.expectedUpstreamMap), len(dnsServer.dnsMuxHandlers))
+			}
+
+			for _, expected := range testCase.expectedUpstreamMap {
+				found := false
+				for _, got := range dnsServer.dnsMuxHandlers {
+					if got.domain == expected.domain && got.priority == expected.priority {
+						found = true
+						break
+					}
+				}
+				if !found {
+					t.Fatalf("update upstream failed, handler for domain=%s priority=%d not found in dnsMuxHandlers: %#v", expected.domain, expected.priority, dnsServer.dnsMuxHandlers)
+				}
+			}
+
+			var responseMSG *dns.Msg
+			responseWriter := &test.MockResponseWriter{
+				WriteMsgFunc: func(m *dns.Msg) error {
+					responseMSG = m
+					return nil
+				},
+			}
+			for _, q := range testCase.expectedLocalQs {
+				dnsServer.localResolver.ServeDNS(responseWriter, &dns.Msg{
+					Question: []dns.Question{q},
+				})
+			}
+
+			if len(testCase.expectedLocalQs) > 0 {
+				assert.NotNil(t, responseMSG, "response message should not be nil")
+				assert.Equal(t, dns.RcodeSuccess, responseMSG.Rcode, "response code should be success")
+				assert.NotEmpty(t, responseMSG.Answer, "response message should have answers")
+			}
+		})
+	}
+}
+
+func TestDNSFakeResolverHandleUpdates(t *testing.T) {
+	ov := os.Getenv("NB_WG_KERNEL_DISABLED")
+	defer t.Setenv("NB_WG_KERNEL_DISABLED", ov)
+
+	t.Setenv("NB_WG_KERNEL_DISABLED", "true")
+	newNet, err := stdnet.NewNet(context.Background(), []string{"utun2301"})
+	if err != nil {
+		t.Errorf("create stdnet: %v", err)
+		return
+	}
+
+	privKey, _ := wgtypes.GeneratePrivateKey()
+	opts := iface.WGIFaceOpts{
+		IFaceName:    "utun2301",
+		Address:      wgaddr.MustParseWGAddress("100.66.100.1/32"),
+		WGPort:       33100,
+		WGPrivKey:    privKey.String(),
+		MTU:          iface.DefaultMTU,
+		TransportNet: newNet,
+	}
+	wgIface, err := iface.NewWGIFace(opts)
+	if err != nil {
+		t.Errorf("build interface wireguard: %v", err)
+		return
+	}
+
+	err = wgIface.Create()
+	if err != nil {
+		t.Errorf("create and init wireguard interface: %v", err)
+		return
+	}
+	defer func() {
+		if err = wgIface.Close(); err != nil {
+			t.Logf("close wireguard interface: %v", err)
+		}
+	}()
+
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+
+	packetfilter := pfmock.NewMockPacketFilter(ctrl)
+	packetfilter.EXPECT().FilterOutbound(gomock.Any(), gomock.Any()).AnyTimes()
+	packetfilter.EXPECT().SetUDPPacketHook(gomock.Any(), gomock.Any(), gomock.Any()).AnyTimes()
+	packetfilter.EXPECT().SetTCPPacketHook(gomock.Any(), gomock.Any(), gomock.Any()).AnyTimes()
+
+	if err := wgIface.SetFilter(packetfilter); err != nil {
+		t.Errorf("set packet filter: %v", err)
+		return
+	}
+
+	dnsServer, err := NewDefaultServer(context.Background(), DefaultServerConfig{
+		WgInterface:    wgIface,
+		CustomAddress:  "",
+		StatusRecorder: peer.NewRecorder("mgm"),
+		StateManager:   nil,
+		DisableSys:     false,
+	})
+	if err != nil {
+		t.Errorf("create DNS server: %v", err)
+		return
+	}
+
+	err = dnsServer.Initialize()
+	if err != nil {
+		t.Errorf("run DNS server: %v", err)
+		return
+	}
+	defer func() {
+		if err = dnsServer.hostManager.restoreHostDNS(); err != nil {
+			t.Logf("restore DNS settings on the host: %v", err)
+			return
+		}
+	}()
+
+	dnsServer.dnsMuxHandlers = []handlerWrapper{
+		{
+			domain:   zoneRecords[0].Name,
+			handler:  &local.Resolver{},
+			priority: PriorityUpstream,
+		},
+	}
+	dnsServer.localResolver.Update([]nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: int(dns.TypeA), Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}})
+	dnsServer.updateSerial = 0
+
+	nameServers := []nbdns.NameServer{
+		{
+			IP:     netip.MustParseAddr("8.8.8.8"),
+			NSType: nbdns.UDPNameServerType,
+			Port:   53,
+		},
+		{
+			IP:     netip.MustParseAddr("8.8.4.4"),
+			NSType: nbdns.UDPNameServerType,
+			Port:   53,
+		},
+	}
+
+	update := nbdns.Config{
+		ServiceEnable: true,
+		CustomZones: []nbdns.CustomZone{
+			{
+				Domain:  "netbird.cloud",
+				Records: zoneRecords,
+			},
+		},
+		NameServerGroups: []*nbdns.NameServerGroup{
+			{
+				Domains:     []string{"netbird.io"},
+				NameServers: nameServers,
+			},
+			{
+				NameServers: nameServers,
+				Primary:     true,
+			},
+		},
+	}
+
+	// Start the server with regular configuration
+	if err := dnsServer.UpdateDNSServer(1, update); err != nil {
+		t.Fatalf("update dns server should not fail, got error: %v", err)
+		return
+	}
+
+	update2 := update
+	update2.ServiceEnable = false
+	// Disable the server, stop the listener
+	if err := dnsServer.UpdateDNSServer(2, update2); err != nil {
+		t.Fatalf("update dns server should not fail, got error: %v", err)
+		return
+	}
+
+	update3 := update2
+	update3.NameServerGroups = update3.NameServerGroups[:1]
+	// But service still get updates and we checking that we handle
+	// internal state in the right way
+	if err := dnsServer.UpdateDNSServer(3, update3); err != nil {
+		t.Fatalf("update dns server should not fail, got error: %v", err)
+		return
+	}
+}

client/internal/dns/server_test.go

@@ -10,7 +10,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang/mock/gomock"
 	"github.com/miekg/dns"
 	log "github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"
@@ -23,7 +22,6 @@ import (
 	"github.com/netbirdio/netbird/client/iface"
 	"github.com/netbirdio/netbird/client/iface/configurer"
 	"github.com/netbirdio/netbird/client/iface/device"
-	pfmock "github.com/netbirdio/netbird/client/iface/mocks"
 	"github.com/netbirdio/netbird/client/iface/wgaddr"
 	"github.com/netbirdio/netbird/client/internal/dns/local"
 	"github.com/netbirdio/netbird/client/internal/dns/test"
@@ -104,481 +102,6 @@ func init() {
 	formatter.SetTextFormatter(log.StandardLogger())
 }
 
-func generateDummyHandler(d string, servers []nbdns.NameServer) *upstreamResolverBase {
-	var srvs []netip.AddrPort
-	for _, srv := range servers {
-		srvs = append(srvs, srv.AddrPort())
-	}
-	u := &upstreamResolverBase{
-		domain: domain.Domain(d),
-		cancel: func() {},
-	}
-	u.addRace(srvs)
-	return u
-}
-
-func TestUpdateDNSServer(t *testing.T) {
-
-	nameServers := []nbdns.NameServer{
-		{
-			IP:     netip.MustParseAddr("8.8.8.8"),
-			NSType: nbdns.UDPNameServerType,
-			Port:   53,
-		},
-		{
-			IP:     netip.MustParseAddr("8.8.4.4"),
-			NSType: nbdns.UDPNameServerType,
-			Port:   53,
-		},
-	}
-
-	dummyHandler := local.NewResolver()
-
-	testCases := []struct {
-		name                string
-		initUpstreamMap     registeredHandlerMap
-		initLocalZones      []nbdns.CustomZone
-		initSerial          uint64
-		inputSerial         uint64
-		inputUpdate         nbdns.Config
-		shouldFail          bool
-		expectedUpstreamMap registeredHandlerMap
-		expectedLocalQs     []dns.Question
-	}{
-		{
-			name:            "Initial Config Should Succeed",
-			initUpstreamMap: make(registeredHandlerMap),
-			initSerial:      0,
-			inputSerial:     1,
-			inputUpdate: nbdns.Config{
-				ServiceEnable: true,
-				CustomZones: []nbdns.CustomZone{
-					{
-						Domain:  "netbird.cloud",
-						Records: zoneRecords,
-					},
-				},
-				NameServerGroups: []*nbdns.NameServerGroup{
-					{
-						Domains:     []string{"netbird.io"},
-						NameServers: nameServers,
-					},
-					{
-						NameServers: nameServers,
-						Primary:     true,
-					},
-				},
-			},
-			expectedUpstreamMap: registeredHandlerMap{
-				generateDummyHandler("netbird.io", nameServers).ID(): handlerWrapper{
-					domain:   "netbird.io",
-					handler:  dummyHandler,
-					priority: PriorityUpstream,
-				},
-				dummyHandler.ID(): handlerWrapper{
-					domain:   "netbird.cloud",
-					handler:  dummyHandler,
-					priority: PriorityLocal,
-				},
-				generateDummyHandler(".", nameServers).ID(): handlerWrapper{
-					domain:   nbdns.RootZone,
-					handler:  dummyHandler,
-					priority: PriorityDefault,
-				},
-			},
-			expectedLocalQs: []dns.Question{{Name: "peera.netbird.cloud.", Qtype: dns.TypeA, Qclass: dns.ClassINET}},
-		},
-		{
-			name:           "New Config Should Succeed",
-			initLocalZones: []nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: 1, Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}},
-			initUpstreamMap: registeredHandlerMap{
-				generateDummyHandler(zoneRecords[0].Name, nameServers).ID(): handlerWrapper{
-					domain:   "netbird.cloud",
-					handler:  dummyHandler,
-					priority: PriorityUpstream,
-				},
-			},
-			initSerial:  0,
-			inputSerial: 1,
-			inputUpdate: nbdns.Config{
-				ServiceEnable: true,
-				CustomZones: []nbdns.CustomZone{
-					{
-						Domain:  "netbird.cloud",
-						Records: zoneRecords,
-					},
-				},
-				NameServerGroups: []*nbdns.NameServerGroup{
-					{
-						Domains:     []string{"netbird.io"},
-						NameServers: nameServers,
-					},
-				},
-			},
-			expectedUpstreamMap: registeredHandlerMap{
-				generateDummyHandler("netbird.io", nameServers).ID(): handlerWrapper{
-					domain:   "netbird.io",
-					handler:  dummyHandler,
-					priority: PriorityUpstream,
-				},
-				"local-resolver": handlerWrapper{
-					domain:   "netbird.cloud",
-					handler:  dummyHandler,
-					priority: PriorityLocal,
-				},
-			},
-			expectedLocalQs: []dns.Question{{Name: zoneRecords[0].Name, Qtype: 1, Qclass: 1}},
-		},
-		{
-			name:            "Smaller Config Serial Should Be Skipped",
-			initLocalZones:  []nbdns.CustomZone{},
-			initUpstreamMap: make(registeredHandlerMap),
-			initSerial:      2,
-			inputSerial:     1,
-			shouldFail:      true,
-		},
-		{
-			name:            "Empty NS Group Domain Or Not Primary Element Should Fail",
-			initLocalZones:  []nbdns.CustomZone{},
-			initUpstreamMap: make(registeredHandlerMap),
-			initSerial:      0,
-			inputSerial:     1,
-			inputUpdate: nbdns.Config{
-				ServiceEnable: true,
-				CustomZones: []nbdns.CustomZone{
-					{
-						Domain:  "netbird.cloud",
-						Records: zoneRecords,
-					},
-				},
-				NameServerGroups: []*nbdns.NameServerGroup{
-					{
-						NameServers: nameServers,
-					},
-				},
-			},
-			shouldFail: true,
-		},
-		{
-			name:            "Invalid NS Group Nameservers list Should Fail",
-			initLocalZones:  []nbdns.CustomZone{},
-			initUpstreamMap: make(registeredHandlerMap),
-			initSerial:      0,
-			inputSerial:     1,
-			inputUpdate: nbdns.Config{
-				ServiceEnable: true,
-				CustomZones: []nbdns.CustomZone{
-					{
-						Domain:  "netbird.cloud",
-						Records: zoneRecords,
-					},
-				},
-				NameServerGroups: []*nbdns.NameServerGroup{
-					{
-						NameServers: nameServers,
-					},
-				},
-			},
-			shouldFail: true,
-		},
-		{
-			name:            "Invalid Custom Zone Records list Should Skip",
-			initLocalZones:  []nbdns.CustomZone{},
-			initUpstreamMap: make(registeredHandlerMap),
-			initSerial:      0,
-			inputSerial:     1,
-			inputUpdate: nbdns.Config{
-				ServiceEnable: true,
-				CustomZones: []nbdns.CustomZone{
-					{
-						Domain: "netbird.cloud",
-					},
-				},
-				NameServerGroups: []*nbdns.NameServerGroup{
-					{
-						NameServers: nameServers,
-						Primary:     true,
-					},
-				},
-			},
-			expectedUpstreamMap: registeredHandlerMap{generateDummyHandler(".", nameServers).ID(): handlerWrapper{
-				domain:   ".",
-				handler:  dummyHandler,
-				priority: PriorityDefault,
-			}},
-		},
-		{
-			name:           "Empty Config Should Succeed and Clean Maps",
-			initLocalZones: []nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: int(dns.TypeA), Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}},
-			initUpstreamMap: registeredHandlerMap{
-				generateDummyHandler(zoneRecords[0].Name, nameServers).ID(): handlerWrapper{
-					domain:   zoneRecords[0].Name,
-					handler:  dummyHandler,
-					priority: PriorityUpstream,
-				},
-			},
-			initSerial:          0,
-			inputSerial:         1,
-			inputUpdate:         nbdns.Config{ServiceEnable: true},
-			expectedUpstreamMap: make(registeredHandlerMap),
-			expectedLocalQs:     []dns.Question{},
-		},
-		{
-			name:           "Disabled Service Should clean map",
-			initLocalZones: []nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: int(dns.TypeA), Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}},
-			initUpstreamMap: registeredHandlerMap{
-				generateDummyHandler(zoneRecords[0].Name, nameServers).ID(): handlerWrapper{
-					domain:   zoneRecords[0].Name,
-					handler:  dummyHandler,
-					priority: PriorityUpstream,
-				},
-			},
-			initSerial:          0,
-			inputSerial:         1,
-			inputUpdate:         nbdns.Config{ServiceEnable: false},
-			expectedUpstreamMap: make(registeredHandlerMap),
-			expectedLocalQs:     []dns.Question{},
-		},
-	}
-
-	for n, testCase := range testCases {
-		t.Run(testCase.name, func(t *testing.T) {
-			privKey, _ := wgtypes.GenerateKey()
-			newNet, err := stdnet.NewNet(context.Background(), nil)
-			if err != nil {
-				t.Fatal(err)
-			}
-
-			opts := iface.WGIFaceOpts{
-				IFaceName:    fmt.Sprintf("utun230%d", n),
-				Address:      wgaddr.MustParseWGAddress(fmt.Sprintf("100.66.100.%d/32", n+1)),
-				WGPort:       33100,
-				WGPrivKey:    privKey.String(),
-				MTU:          iface.DefaultMTU,
-				TransportNet: newNet,
-			}
-
-			wgIface, err := iface.NewWGIFace(opts)
-			if err != nil {
-				t.Fatal(err)
-			}
-			err = wgIface.Create()
-			if err != nil {
-				t.Fatal(err)
-			}
-			defer func() {
-				err = wgIface.Close()
-				if err != nil {
-					t.Log(err)
-				}
-			}()
-			dnsServer, err := NewDefaultServer(context.Background(), DefaultServerConfig{
-				WgInterface:    wgIface,
-				CustomAddress:  "",
-				StatusRecorder: peer.NewRecorder("mgm"),
-				StateManager:   nil,
-				DisableSys:     false,
-			})
-			if err != nil {
-				t.Fatal(err)
-			}
-			err = dnsServer.Initialize()
-			if err != nil {
-				t.Fatal(err)
-			}
-			defer func() {
-				err = dnsServer.hostManager.restoreHostDNS()
-				if err != nil {
-					t.Log(err)
-				}
-			}()
-
-			dnsServer.dnsMuxMap = testCase.initUpstreamMap
-			dnsServer.localResolver.Update(testCase.initLocalZones)
-			dnsServer.updateSerial = testCase.initSerial
-
-			err = dnsServer.UpdateDNSServer(testCase.inputSerial, testCase.inputUpdate)
-			if err != nil {
-				if testCase.shouldFail {
-					return
-				}
-				t.Fatalf("update dns server should not fail, got error: %v", err)
-			}
-
-			if len(dnsServer.dnsMuxMap) != len(testCase.expectedUpstreamMap) {
-				t.Fatalf("update upstream failed, map size is different than expected, want %d, got %d", len(testCase.expectedUpstreamMap), len(dnsServer.dnsMuxMap))
-			}
-
-			for key := range testCase.expectedUpstreamMap {
-				_, found := dnsServer.dnsMuxMap[key]
-				if !found {
-					t.Fatalf("update upstream failed, key %s was not found in the dnsMuxMap: %#v", key, dnsServer.dnsMuxMap)
-				}
-			}
-
-			var responseMSG *dns.Msg
-			responseWriter := &test.MockResponseWriter{
-				WriteMsgFunc: func(m *dns.Msg) error {
-					responseMSG = m
-					return nil
-				},
-			}
-			for _, q := range testCase.expectedLocalQs {
-				dnsServer.localResolver.ServeDNS(responseWriter, &dns.Msg{
-					Question: []dns.Question{q},
-				})
-			}
-
-			if len(testCase.expectedLocalQs) > 0 {
-				assert.NotNil(t, responseMSG, "response message should not be nil")
-				assert.Equal(t, dns.RcodeSuccess, responseMSG.Rcode, "response code should be success")
-				assert.NotEmpty(t, responseMSG.Answer, "response message should have answers")
-			}
-		})
-	}
-}
-
-func TestDNSFakeResolverHandleUpdates(t *testing.T) {
-	ov := os.Getenv("NB_WG_KERNEL_DISABLED")
-	defer t.Setenv("NB_WG_KERNEL_DISABLED", ov)
-
-	t.Setenv("NB_WG_KERNEL_DISABLED", "true")
-	newNet, err := stdnet.NewNet(context.Background(), []string{"utun2301"})
-	if err != nil {
-		t.Errorf("create stdnet: %v", err)
-		return
-	}
-
-	privKey, _ := wgtypes.GeneratePrivateKey()
-	opts := iface.WGIFaceOpts{
-		IFaceName:    "utun2301",
-		Address:      wgaddr.MustParseWGAddress("100.66.100.1/32"),
-		WGPort:       33100,
-		WGPrivKey:    privKey.String(),
-		MTU:          iface.DefaultMTU,
-		TransportNet: newNet,
-	}
-	wgIface, err := iface.NewWGIFace(opts)
-	if err != nil {
-		t.Errorf("build interface wireguard: %v", err)
-		return
-	}
-
-	err = wgIface.Create()
-	if err != nil {
-		t.Errorf("create and init wireguard interface: %v", err)
-		return
-	}
-	defer func() {
-		if err = wgIface.Close(); err != nil {
-			t.Logf("close wireguard interface: %v", err)
-		}
-	}()
-
-	ctrl := gomock.NewController(t)
-	defer ctrl.Finish()
-
-	packetfilter := pfmock.NewMockPacketFilter(ctrl)
-	packetfilter.EXPECT().FilterOutbound(gomock.Any(), gomock.Any()).AnyTimes()
-	packetfilter.EXPECT().SetUDPPacketHook(gomock.Any(), gomock.Any(), gomock.Any()).AnyTimes()
-	packetfilter.EXPECT().SetTCPPacketHook(gomock.Any(), gomock.Any(), gomock.Any()).AnyTimes()
-
-	if err := wgIface.SetFilter(packetfilter); err != nil {
-		t.Errorf("set packet filter: %v", err)
-		return
-	}
-
-	dnsServer, err := NewDefaultServer(context.Background(), DefaultServerConfig{
-		WgInterface:    wgIface,
-		CustomAddress:  "",
-		StatusRecorder: peer.NewRecorder("mgm"),
-		StateManager:   nil,
-		DisableSys:     false,
-	})
-	if err != nil {
-		t.Errorf("create DNS server: %v", err)
-		return
-	}
-
-	err = dnsServer.Initialize()
-	if err != nil {
-		t.Errorf("run DNS server: %v", err)
-		return
-	}
-	defer func() {
-		if err = dnsServer.hostManager.restoreHostDNS(); err != nil {
-			t.Logf("restore DNS settings on the host: %v", err)
-			return
-		}
-	}()
-
-	dnsServer.dnsMuxMap = registeredHandlerMap{
-		"id1": handlerWrapper{
-			domain:   zoneRecords[0].Name,
-			handler:  &local.Resolver{},
-			priority: PriorityUpstream,
-		},
-	}
-	dnsServer.localResolver.Update([]nbdns.CustomZone{{Domain: "netbird.cloud", Records: []nbdns.SimpleRecord{{Name: "netbird.cloud", Type: int(dns.TypeA), Class: nbdns.DefaultClass, TTL: 300, RData: "10.0.0.1"}}}})
-	dnsServer.updateSerial = 0
-
-	nameServers := []nbdns.NameServer{
-		{
-			IP:     netip.MustParseAddr("8.8.8.8"),
-			NSType: nbdns.UDPNameServerType,
-			Port:   53,
-		},
-		{
-			IP:     netip.MustParseAddr("8.8.4.4"),
-			NSType: nbdns.UDPNameServerType,
-			Port:   53,
-		},
-	}
-
-	update := nbdns.Config{
-		ServiceEnable: true,
-		CustomZones: []nbdns.CustomZone{
-			{
-				Domain:  "netbird.cloud",
-				Records: zoneRecords,
-			},
-		},
-		NameServerGroups: []*nbdns.NameServerGroup{
-			{
-				Domains:     []string{"netbird.io"},
-				NameServers: nameServers,
-			},
-			{
-				NameServers: nameServers,
-				Primary:     true,
-			},
-		},
-	}
-
-	// Start the server with regular configuration
-	if err := dnsServer.UpdateDNSServer(1, update); err != nil {
-		t.Fatalf("update dns server should not fail, got error: %v", err)
-		return
-	}
-
-	update2 := update
-	update2.ServiceEnable = false
-	// Disable the server, stop the listener
-	if err := dnsServer.UpdateDNSServer(2, update2); err != nil {
-		t.Fatalf("update dns server should not fail, got error: %v", err)
-		return
-	}
-
-	update3 := update2
-	update3.NameServerGroups = update3.NameServerGroups[:1]
-	// But service still get updates and we checking that we handle
-	// internal state in the right way
-	if err := dnsServer.UpdateDNSServer(3, update3); err != nil {
-		t.Fatalf("update dns server should not fail, got error: %v", err)
-		return
-	}
-}
-
 func TestDNSServerStartStop(t *testing.T) {
 	testCases := []struct {
 		name     string
@@ -1029,15 +552,15 @@ func (m *mockService) RegisterMux(string, dns.Handler) {}
 func (m *mockService) DeregisterMux(string)            {}
 
 func TestDefaultServer_UpdateMux(t *testing.T) {
-	baseMatchHandlers := registeredHandlerMap{
-		"upstream-group1": {
+	baseMatchHandlers := []handlerWrapper{
+		{
 			domain: "example.com",
 			handler: &mockHandler{
 				Id: "upstream-group1",
 			},
 			priority: PriorityUpstream,
 		},
-		"upstream-group2": {
+		{
 			domain: "example.com",
 			handler: &mockHandler{
 				Id: "upstream-group2",
@@ -1046,15 +569,15 @@ func TestDefaultServer_UpdateMux(t *testing.T) {
 		},
 	}
 
-	baseRootHandlers := registeredHandlerMap{
-		"upstream-root1": {
+	baseRootHandlers := []handlerWrapper{
+		{
 			domain: ".",
 			handler: &mockHandler{
 				Id: "upstream-root1",
 			},
 			priority: PriorityDefault,
 		},
-		"upstream-root2": {
+		{
 			domain: ".",
 			handler: &mockHandler{
 				Id: "upstream-root2",
@@ -1063,22 +586,22 @@ func TestDefaultServer_UpdateMux(t *testing.T) {
 		},
 	}
 
-	baseMixedHandlers := registeredHandlerMap{
-		"upstream-group1": {
+	baseMixedHandlers := []handlerWrapper{
+		{
 			domain: "example.com",
 			handler: &mockHandler{
 				Id: "upstream-group1",
 			},
 			priority: PriorityUpstream,
 		},
-		"upstream-group2": {
+		{
 			domain: "example.com",
 			handler: &mockHandler{
 				Id: "upstream-group2",
 			},
 			priority: PriorityUpstream - 1,
 		},
-		"upstream-other": {
+		{
 			domain: "other.com",
 			handler: &mockHandler{
 				Id: "upstream-other",
@@ -1089,7 +612,7 @@ func TestDefaultServer_UpdateMux(t *testing.T) {
 
 	tests := []struct {
 		name             string
-		initialHandlers  registeredHandlerMap
+		initialHandlers  []handlerWrapper
 		updates          []handlerWrapper
 		expectedHandlers map[string]string // map[HandlerID]domain
 		description      string
@@ -1373,32 +896,38 @@ func TestDefaultServer_UpdateMux(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			server := &DefaultServer{
-				dnsMuxMap:    tt.initialHandlers,
-				handlerChain: NewHandlerChain(),
-				service:      &mockService{},
+				dnsMuxHandlers: tt.initialHandlers,
+				handlerChain:   NewHandlerChain(),
+				service:        &mockService{},
 			}
 
 			// Perform the update
 			server.updateMux(tt.updates)
 
 			// Verify the results
-			assert.Equal(t, len(tt.expectedHandlers), len(server.dnsMuxMap),
+			assert.Equal(t, len(tt.expectedHandlers), len(server.dnsMuxHandlers),
 				"Number of handlers after update doesn't match expected")
 
 			// Check each expected handler
 			for id, expectedDomain := range tt.expectedHandlers {
-				handler, exists := server.dnsMuxMap[types.HandlerID(id)]
-				assert.True(t, exists, "Expected handler %s not found", id)
-				if exists {
-					assert.Equal(t, expectedDomain, handler.domain,
+				var found *handlerWrapper
+				for i := range server.dnsMuxHandlers {
+					if server.dnsMuxHandlers[i].handler.ID() == types.HandlerID(id) {
+						found = &server.dnsMuxHandlers[i]
+						break
+					}
+				}
+				assert.NotNil(t, found, "Expected handler %s not found", id)
+				if found != nil {
+					assert.Equal(t, expectedDomain, found.domain,
 						"Domain mismatch for handler %s", id)
 				}
 			}
 
 			// Verify no unexpected handlers exist
-			for HandlerID := range server.dnsMuxMap {
-				_, expected := tt.expectedHandlers[string(HandlerID)]
-				assert.True(t, expected, "Unexpected handler found: %s", HandlerID)
+			for _, entry := range server.dnsMuxHandlers {
+				_, expected := tt.expectedHandlers[string(entry.handler.ID())]
+				assert.True(t, expected, "Unexpected handler found: %s", entry.handler.ID())
 			}
 
 			// Verify the handlerChain state and order
@@ -1413,7 +942,7 @@ func TestDefaultServer_UpdateMux(t *testing.T) {
 
 				// Verify handler exists in mux
 				foundInMux := false
-				for _, muxEntry := range server.dnsMuxMap {
+				for _, muxEntry := range server.dnsMuxHandlers {
 					if chainEntry.Handler == muxEntry.handler &&
 						chainEntry.Priority == muxEntry.priority &&
 						chainEntry.Pattern == dns.Fqdn(muxEntry.domain) {
@@ -1422,12 +951,108 @@ func TestDefaultServer_UpdateMux(t *testing.T) {
 					}
 				}
 				assert.True(t, foundInMux,
-					"Handler in chain not found in dnsMuxMap")
+					"Handler in chain not found in dnsMuxHandlers")
 			}
 		})
 	}
 }
 
+// chainHasPattern reports whether the handler chain holds an entry registered
+// for the given fqdn pattern at the given priority.
+func chainHasPattern(s *DefaultServer, pattern string, priority int) bool {
+	for _, h := range s.handlerChain.handlers {
+		if h.OrigPattern == pattern && h.Priority == priority {
+			return true
+		}
+	}
+	return false
+}
+
+// TestDefaultServer_UpdateMux_SharedHandlerZoneRemoval verifies that updateMux
+// tracks each (handler, domain) registration independently when one handler
+// serves multiple zones. Every custom zone is served by the same handler
+// instance (the local resolver, whose ID is the constant "local-resolver"), so
+// removing one zone must deregister exactly that zone's chain entry and leave
+// the others in place. Tracking registrations by handler ID alone collapses all
+// zones onto one entry, leaving removed zones in the chain to answer
+// authoritatively with no records.
+func TestDefaultServer_UpdateMux_SharedHandlerZoneRemoval(t *testing.T) {
+	// One handler serves every custom zone, mirroring s.localResolver.
+	shared := &mockHandler{Id: "local-resolver"}
+
+	server := &DefaultServer{
+		handlerChain: NewHandlerChain(),
+		service:      &mockService{},
+	}
+
+	// Two custom zones under the same handler. The surviving zone is registered
+	// last, mirroring the management emission order.
+	server.updateMux([]handlerWrapper{
+		{domain: "userzone.test", handler: shared, priority: PriorityLocal},
+		{domain: "peerzone.test", handler: shared, priority: PriorityLocal},
+	})
+
+	require.True(t, chainHasPattern(server, "userzone.test.", PriorityLocal),
+		"userzone.test should be registered after the first update")
+	require.True(t, chainHasPattern(server, "peerzone.test.", PriorityLocal),
+		"peerzone.test should be registered after the first update")
+
+	// Remove one zone, keep the other.
+	server.updateMux([]handlerWrapper{
+		{domain: "peerzone.test", handler: shared, priority: PriorityLocal},
+	})
+
+	assert.True(t, chainHasPattern(server, "peerzone.test.", PriorityLocal),
+		"peerzone.test should remain after removing userzone.test")
+	assert.False(t, chainHasPattern(server, "userzone.test.", PriorityLocal),
+		"userzone.test handler must be deregistered, not leaked in the chain")
+}
+
+// TestDefaultServer_UpdateMux_PreservesLocalResolver verifies that updateMux
+// does not tear down the shared local resolver during reconfiguration. The
+// resolver is a process-lifetime singleton reused across config updates;
+// Stop() cancels its lookup context (breaking external CNAME-target
+// resolution) and clears its records. updateMux must deregister its chain
+// entries without stopping it. Records surviving a teardown update is the
+// observable proxy: Stop() would have cleared them.
+func TestDefaultServer_UpdateMux_PreservesLocalResolver(t *testing.T) {
+	resolver := local.NewResolver()
+	require.NoError(t, resolver.RegisterRecord(nbdns.SimpleRecord{
+		Name:  "peer.netbird.cloud.",
+		Type:  int(dns.TypeA),
+		Class: nbdns.DefaultClass,
+		TTL:   300,
+		RData: "10.0.0.1",
+	}))
+
+	server := &DefaultServer{
+		handlerChain:  NewHandlerChain(),
+		service:       &mockService{},
+		localResolver: resolver,
+	}
+
+	server.updateMux([]handlerWrapper{
+		{domain: "netbird.cloud", handler: resolver, priority: PriorityLocal},
+	})
+
+	// Remove the zone. The resolver must survive so its records and lookup
+	// context stay intact for the next registration.
+	server.updateMux(nil)
+
+	var response *dns.Msg
+	resolver.ServeDNS(&test.MockResponseWriter{
+		WriteMsgFunc: func(m *dns.Msg) error {
+			response = m
+			return nil
+		},
+	}, &dns.Msg{Question: []dns.Question{{Name: "peer.netbird.cloud.", Qtype: dns.TypeA, Qclass: dns.ClassINET}}})
+
+	require.NotNil(t, response, "local resolver should answer after teardown")
+	assert.Equal(t, dns.RcodeSuccess, response.Rcode,
+		"local resolver records must survive teardown; updateMux must not Stop() the shared resolver")
+	assert.NotEmpty(t, response.Answer, "answer should contain the surviving record")
+}
+
 func TestExtraDomains(t *testing.T) {
 	tests := []struct {
 		name                string
@@ -2049,7 +1674,6 @@ func TestBuildUpstreamHandler_MergesGroupsPerDomain(t *testing.T) {
 		localResolver: local.NewResolver(),
 		handlerChain:  NewHandlerChain(),
 		hostManager:   &noopHostConfigurator{},
-		dnsMuxMap:     make(registeredHandlerMap),
 	}
 
 	groups := []*nbdns.NameServerGroup{
@@ -2207,7 +1831,7 @@ func TestEvaluateNSGroupHealth(t *testing.T) {
 	}
 }
 
-// healthStubHandler is a minimal dnsMuxMap entry that exposes a fixed
+// healthStubHandler is a minimal dnsMuxHandlers entry that exposes a fixed
 // UpstreamHealth snapshot, letting tests drive recomputeNSGroupStates
 // without spinning up real handlers.
 type healthStubHandler struct {
@@ -2283,12 +1907,11 @@ func newProjTestFixture(t *testing.T) *projTestFixture {
 		ctx:              context.Background(),
 		wgInterface:      &mocWGIface{},
 		statusRecorder:   recorder,
-		dnsMuxMap:        make(registeredHandlerMap),
 		selectedRoutes:   func() route.HAMap { return fx.selected },
 		activeRoutes:     func() route.HAMap { return fx.active },
 		warningDelayBase: defaultWarningDelayBase,
 	}
-	fx.server.dnsMuxMap["example.com"] = handlerWrapper{domain: "example.com", handler: fx.stub, priority: PriorityUpstream}
+	fx.server.dnsMuxHandlers = []handlerWrapper{{domain: "example.com", handler: fx.stub, priority: PriorityUpstream}}
 
 	fx.server.mux.Lock()
 	fx.server.updateNSGroupStates([]*nbdns.NameServerGroup{fx.group})
@@ -2395,7 +2018,6 @@ func TestProjection_OverlayAddrNoRouteDelaysWarning(t *testing.T) {
 		ctx:              context.Background(),
 		wgInterface:      &mocWGIface{},
 		statusRecorder:   recorder,
-		dnsMuxMap:        make(registeredHandlerMap),
 		selectedRoutes:   func() route.HAMap { return nil },
 		activeRoutes:     func() route.HAMap { return nil },
 		warningDelayBase: 50 * time.Millisecond,
@@ -2407,7 +2029,7 @@ func TestProjection_OverlayAddrNoRouteDelaysWarning(t *testing.T) {
 	stub := &healthStubHandler{health: map[netip.AddrPort]UpstreamHealth{
 		overlayPeer: {LastFail: time.Now(), LastErr: "timeout"},
 	}}
-	server.dnsMuxMap["example.com"] = handlerWrapper{domain: "example.com", handler: stub, priority: PriorityUpstream}
+	server.dnsMuxHandlers = []handlerWrapper{{domain: "example.com", handler: stub, priority: PriorityUpstream}}
 
 	server.mux.Lock()
 	server.updateNSGroupStates([]*nbdns.NameServerGroup{group})
@@ -2444,7 +2066,6 @@ func TestProjection_StopClearsHealthState(t *testing.T) {
 		service:           NewServiceViaMemory(wgIface),
 		hostManager:       &noopHostConfigurator{},
 		extraDomains:      map[domain.Domain]int{},
-		dnsMuxMap:         make(registeredHandlerMap),
 		statusRecorder:    peer.NewRecorder("mgm"),
 		selectedRoutes:    func() route.HAMap { return nil },
 		activeRoutes:      func() route.HAMap { return nil },
@@ -2459,7 +2080,7 @@ func TestProjection_StopClearsHealthState(t *testing.T) {
 		NameServers: []nbdns.NameServer{{IP: srv.Addr(), NSType: nbdns.UDPNameServerType, Port: int(srv.Port())}},
 	}
 	stub := &healthStubHandler{health: map[netip.AddrPort]UpstreamHealth{srv: {LastOk: time.Now()}}}
-	server.dnsMuxMap["example.com"] = handlerWrapper{domain: "example.com", handler: stub, priority: PriorityUpstream}
+	server.dnsMuxHandlers = []handlerWrapper{{domain: "example.com", handler: stub, priority: PriorityUpstream}}
 
 	server.mux.Lock()
 	server.updateNSGroupStates([]*nbdns.NameServerGroup{group})
@@ -2484,6 +2105,32 @@ func TestProjection_StopClearsHealthState(t *testing.T) {
 // rule 3: startup failures while the peer is handshaking, then the peer
 // comes up and a query succeeds before the grace window elapses. No
 // warning should ever have fired, and no recovery either.
+func TestWarningDelayBaseFromEnv(t *testing.T) {
+	tests := []struct {
+		name string
+		set  bool
+		val  string
+		want time.Duration
+	}{
+		{name: "unset uses default", set: false, want: defaultWarningDelayBase},
+		{name: "valid override", set: true, val: "90s", want: 90 * time.Second},
+		{name: "valid minutes", set: true, val: "2m", want: 2 * time.Minute},
+		{name: "invalid falls back", set: true, val: "notaduration", want: defaultWarningDelayBase},
+		{name: "zero falls back", set: true, val: "0s", want: defaultWarningDelayBase},
+		{name: "negative falls back", set: true, val: "-30s", want: defaultWarningDelayBase},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Setenv(envWarningDelay, tc.val)
+			if !tc.set {
+				os.Unsetenv(envWarningDelay)
+			}
+			assert.Equal(t, tc.want, warningDelayBaseFromEnv(), "grace window base")
+		})
+	}
+}
+
 func TestProjection_OverlayRecoversDuringGrace(t *testing.T) {
 	fx := newProjTestFixture(t)
 	fx.server.warningDelayBase = 200 * time.Millisecond
@@ -2595,7 +2242,6 @@ func TestProjection_MixedGroupEmitsImmediately(t *testing.T) {
 	server := &DefaultServer{
 		ctx:              context.Background(),
 		statusRecorder:   recorder,
-		dnsMuxMap:        make(registeredHandlerMap),
 		selectedRoutes:   func() route.HAMap { return overlayMap },
 		activeRoutes:     func() route.HAMap { return nil },
 		warningDelayBase: time.Hour,
@@ -2613,7 +2259,7 @@ func TestProjection_MixedGroupEmitsImmediately(t *testing.T) {
 			overlay: {LastFail: time.Now(), LastErr: "timeout"},
 		},
 	}
-	server.dnsMuxMap["example.com"] = handlerWrapper{domain: "example.com", handler: stub, priority: PriorityUpstream}
+	server.dnsMuxHandlers = []handlerWrapper{{domain: "example.com", handler: stub, priority: PriorityUpstream}}
 
 	server.mux.Lock()
 	server.updateNSGroupStates([]*nbdns.NameServerGroup{group})
@@ -2640,7 +2286,6 @@ func TestDNSLoopPrevention(t *testing.T) {
 		localResolver: local.NewResolver(),
 		handlerChain:  NewHandlerChain(),
 		hostManager:   &noopHostConfigurator{},
-		dnsMuxMap:     make(registeredHandlerMap),
 	}
 
 	tests := []struct {

client/internal/dns/service_listener.go

@@ -292,18 +292,16 @@ func (s *serviceViaListener) generateFreePort() (uint16, error) {
 		return customPort, nil
 	}
 
-	udpAddr := net.UDPAddrFromAddrPort(netip.MustParseAddrPort("0.0.0.0:0"))
-	probeListener, err := net.ListenUDP("udp", udpAddr)
+	probeListener, err := net.ListenUDP("udp4", &net.UDPAddr{})
 	if err != nil {
 		log.Debugf("failed to bind random port for DNS: %s", err)
 		return 0, err
 	}
 
-	addrPort := netip.MustParseAddrPort(probeListener.LocalAddr().String()) // might panic if address is incorrect
-	err = probeListener.Close()
-	if err != nil {
+	port := uint16(probeListener.LocalAddr().(*net.UDPAddr).Port)
+	if err = probeListener.Close(); err != nil {
 		log.Debugf("failed to free up DNS port: %s", err)
 		return 0, err
 	}
-	return addrPort.Port(), nil
+	return port, nil
 }

client/internal/dns/unclean_shutdown_windows.go

@@ -5,9 +5,8 @@ import (
 )
 
 type ShutdownState struct {
-	Guid           string
-	GPO            bool
-	NRPTEntryCount int
+	Guid string
+	GPO  bool
 }
 
 func (s *ShutdownState) Name() string {
@@ -16,9 +15,8 @@ func (s *ShutdownState) Name() string {
 
 func (s *ShutdownState) Cleanup() error {
 	manager := &registryConfigurator{
-		guid:           s.Guid,
-		gpo:            s.GPO,
-		nrptEntryCount: s.NRPTEntryCount,
+		guid: s.Guid,
+		gpo:  s.GPO,
 	}
 
 	if err := manager.restoreUncleanShutdownDNS(); err != nil {

client/internal/dns/upstream.go

@@ -443,29 +443,32 @@ func (u *upstreamResolverBase) queryUpstream(parentCtx context.Context, r *dns.M
 		return raceResult{}, &upstreamFailure{upstream: upstream, reason: "no response"}
 	}
 
+	// A valid response means the upstream is reachable, whatever the Rcode.
+	u.markUpstreamOk(upstream)
+
 	proto := ""
 	if upstreamProto != nil {
 		proto = upstreamProto.protocol
 	}
 
 	if rm.Rcode == dns.RcodeServerFailure || rm.Rcode == dns.RcodeRefused {
+		// SERVFAIL and REFUSED are per-question outcomes (DNSSEC-bogus names,
+		// refused zones, transient recursion errors), not reachability
+		// problems: fail over for a better answer but keep the upstream healthy.
 		if code, ok := nonRetryableEDE(rm); ok {
 			if !hadEdns {
-				stripOPT(rm)
+				resutil.StripOPT(rm)
 			}
-			u.markUpstreamOk(upstream)
 			return raceResult{msg: rm, upstream: upstream, protocol: proto, ede: edeName(code)}, nil
 		}
 		reason := dns.RcodeToString[rm.Rcode]
-		u.markUpstreamFail(upstream, reason)
 		return raceResult{}, &upstreamFailure{upstream: upstream, reason: reason}
 	}
 
 	if !hadEdns {
-		stripOPT(rm)
+		resutil.StripOPT(rm)
 	}
 
-	u.markUpstreamOk(upstream)
 	return raceResult{msg: rm, upstream: upstream, protocol: proto}, nil
 }
 
@@ -520,22 +523,6 @@ func upstreamUDPSize() uint16 {
 	return dns.MinMsgSize
 }
 
-// stripOPT removes any OPT pseudo-RRs from the response's Extra section so
-// the response complies with RFC 6891 when the client did not advertise EDNS0.
-func stripOPT(rm *dns.Msg) {
-	if len(rm.Extra) == 0 {
-		return
-	}
-	out := rm.Extra[:0]
-	for _, rr := range rm.Extra {
-		if _, ok := rr.(*dns.OPT); ok {
-			continue
-		}
-		out = append(out, rr)
-	}
-	rm.Extra = out
-}
-
 func (u *upstreamResolverBase) handleUpstreamError(err error, upstream netip.AddrPort, startTime time.Time) *upstreamFailure {
 	if !errors.Is(err, context.DeadlineExceeded) && !isTimeout(err) {
 		return &upstreamFailure{upstream: upstream, reason: err.Error()}

client/internal/dns/upstream_ios.go

@@ -130,8 +130,3 @@ func GetClientPrivate(iface privateClientIface, upstreamIP netip.Addr, dialTimeo
 	}
 	return client, nil
 }
-
-func getInterfaceIndex(interfaceName string) (int, error) {
-	iface, err := net.InterfaceByName(interfaceName)
-	return iface.Index, err
-}

client/internal/dns/upstream_test.go

@@ -517,6 +517,78 @@ func TestUpstreamResolver_HealthTracking(t *testing.T) {
 	assert.NotContains(t, health, bad, "sibling upstream should not be queried when primary answers")
 }
 
+// TestUpstreamResolver_HealthTracking_ResponseMeansReachable verifies that an
+// upstream which answers with SERVFAIL or REFUSED is recorded as healthy:
+// those are per-question outcomes from a reachable server and must not mark
+// the upstream unhealthy. Only transport failures (timeouts) do.
+func TestUpstreamResolver_HealthTracking_ResponseMeansReachable(t *testing.T) {
+	a := netip.MustParseAddrPort("192.0.2.10:53")
+	b := netip.MustParseAddrPort("192.0.2.11:53")
+	timeoutErr := &net.OpError{Op: "read", Err: fmt.Errorf("i/o timeout")}
+
+	tests := []struct {
+		name        string
+		respA       mockUpstreamResponse
+		respB       mockUpstreamResponse
+		wantHealthy bool
+	}{
+		{
+			name:        "both SERVFAIL are reachable",
+			respA:       mockUpstreamResponse{msg: buildMockResponse(dns.RcodeServerFailure, "")},
+			respB:       mockUpstreamResponse{msg: buildMockResponse(dns.RcodeServerFailure, "")},
+			wantHealthy: true,
+		},
+		{
+			name:        "both REFUSED are reachable",
+			respA:       mockUpstreamResponse{msg: buildMockResponse(dns.RcodeRefused, "")},
+			respB:       mockUpstreamResponse{msg: buildMockResponse(dns.RcodeRefused, "")},
+			wantHealthy: true,
+		},
+		{
+			name:        "timeout marks unhealthy",
+			respA:       mockUpstreamResponse{err: timeoutErr},
+			respB:       mockUpstreamResponse{err: timeoutErr},
+			wantHealthy: false,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			mockClient := &mockUpstreamResolverPerServer{
+				responses: map[string]mockUpstreamResponse{
+					a.String(): tc.respA,
+					b.String(): tc.respB,
+				},
+				rtt: time.Millisecond,
+			}
+
+			ctx, cancel := context.WithCancel(context.Background())
+			defer cancel()
+
+			resolver := &upstreamResolverBase{
+				ctx:             ctx,
+				upstreamClient:  mockClient,
+				upstreamTimeout: UpstreamTimeout,
+			}
+			resolver.addRace([]netip.AddrPort{a, b})
+
+			responseWriter := &test.MockResponseWriter{WriteMsgFunc: func(m *dns.Msg) error { return nil }}
+			resolver.ServeDNS(responseWriter, new(dns.Msg).SetQuestion("example.com.", dns.TypeA))
+
+			health := resolver.UpstreamHealth()
+			require.Contains(t, health, a, "primary upstream should have a health record")
+			if tc.wantHealthy {
+				assert.False(t, health[a].LastOk.IsZero(), "responding upstream should have LastOk set")
+				assert.True(t, health[a].LastFail.IsZero(), "responding upstream should not be marked failed")
+				assert.Empty(t, health[a].LastErr, "responding upstream should have no error")
+			} else {
+				assert.False(t, health[a].LastFail.IsZero(), "timed-out upstream should be marked failed")
+				assert.NotEmpty(t, health[a].LastErr, "timed-out upstream should record an error")
+			}
+		})
+	}
+}
+
 func TestFormatFailures(t *testing.T) {
 	testCases := []struct {
 		name     string
@@ -913,19 +985,6 @@ func TestEDEName(t *testing.T) {
 	assert.Equal(t, "EDE 9999", edeName(9999), "unknown code falls back to numeric")
 }
 
-func TestStripOPT(t *testing.T) {
-	rm := &dns.Msg{
-		Extra: []dns.RR{
-			&dns.OPT{Hdr: dns.RR_Header{Name: ".", Rrtype: dns.TypeOPT}},
-			&dns.A{Hdr: dns.RR_Header{Name: "x.", Rrtype: dns.TypeA}, A: net.IPv4(1, 2, 3, 4)},
-		},
-	}
-	stripOPT(rm)
-	assert.Len(t, rm.Extra, 1, "OPT should be removed, A kept")
-	_, isOPT := rm.Extra[0].(*dns.OPT)
-	assert.False(t, isOPT, "remaining record must not be OPT")
-}
-
 func TestUpstreamResolver_NonRetryableEDEShortCircuits(t *testing.T) {
 	upstream1 := netip.MustParseAddrPort("192.0.2.1:53")
 	upstream2 := netip.MustParseAddrPort("192.0.2.2:53")

client/internal/dns_peer_activator.go

@@ -0,0 +1,76 @@
+package internal
+
+import (
+	"context"
+	"net/netip"
+	"time"
+
+	"github.com/netbirdio/netbird/client/internal/peer"
+	"github.com/netbirdio/netbird/client/internal/peerstore"
+)
+
+const dnsActivationPollInterval = 50 * time.Millisecond
+
+// dnsPeerActivator wakes lazy-connection peers from the DNS resolution path. It
+// implements dns/local.PeerActivator. DNS queries run on their own goroutines,
+// so it only touches state that is safe for concurrent use — ConnMgr.ActivatePeer,
+// peerstore.Store and peer.Status — and never takes the engine's syncMsgMux,
+// keeping DNS resolution from contending with network-map processing.
+type dnsPeerActivator struct {
+	connMgr   *ConnMgr
+	peerStore *peerstore.Store
+	status    *peer.Status
+	// ctx is the engine's long-lived context. The connection dial is tied to it
+	// (not the per-query DNS wait budget) so a handshake that outlasts the wait
+	// still completes in the background rather than being cancelled at the deadline.
+	ctx context.Context
+}
+
+// ActivatePeersByIP triggers wake-up for the peer(s) owning addrs and waits
+// until one is connected or ctx (the per-query DNS wait budget) expires.
+// Activation itself is tied to the engine's long-lived context so the dial
+// survives a wait that times out. Unknown or already-connected addresses are
+// skipped, so the steady-state (warm) path adds no latency.
+func (a *dnsPeerActivator) ActivatePeersByIP(ctx context.Context, addrs []netip.Addr) {
+	if a == nil || a.connMgr == nil {
+		return
+	}
+
+	var pending []string
+	for _, addr := range addrs {
+		ip := addr.String()
+		st, ok := a.status.PeerStateByIP(ip)
+		if !ok || st.ConnStatus == peer.StatusConnected {
+			continue
+		}
+		conn, ok := a.peerStore.PeerConn(st.PubKey)
+		if !ok {
+			continue
+		}
+		a.connMgr.ActivatePeer(a.ctx, conn)
+		pending = append(pending, ip)
+	}
+
+	if len(pending) == 0 {
+		return
+	}
+	a.waitConnected(ctx, pending)
+}
+
+// waitConnected blocks until any of ips reports a connected peer or ctx expires.
+func (a *dnsPeerActivator) waitConnected(ctx context.Context, ips []string) {
+	ticker := time.NewTicker(dnsActivationPollInterval)
+	defer ticker.Stop()
+	for {
+		for _, ip := range ips {
+			if st, ok := a.status.PeerStateByIP(ip); ok && st.ConnStatus == peer.StatusConnected {
+				return
+			}
+		}
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+		}
+	}
+}

client/internal/dns_peer_activator_test.go

@@ -0,0 +1,129 @@
+package internal
+
+import (
+	"context"
+	"net/netip"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/client/internal/peer"
+	"github.com/netbirdio/netbird/client/internal/peerstore"
+)
+
+func newTestPeerConn(t *testing.T, key string) *peer.Conn {
+	t.Helper()
+	conn, err := peer.NewConn(peer.ConnConfig{
+		Key:      key,
+		LocalKey: "local",
+		WgConfig: peer.WgConfig{
+			AllowedIps: []netip.Prefix{netip.MustParsePrefix("100.64.0.1/32")},
+		},
+	}, peer.ServiceDependencies{})
+	require.NoError(t, err)
+	return conn
+}
+
+func newTestDNSPeerActivator(t *testing.T) (*dnsPeerActivator, *peer.Status, *peerstore.Store) {
+	t.Helper()
+	status := peer.NewRecorder("https://mgm")
+	store := peerstore.NewConnStore()
+	// ConnMgr without Start: the lazy manager is nil, so ActivatePeer is a
+	// no-op — these tests exercise the activator's skip/wait logic.
+	connMgr := NewConnMgr(&EngineConfig{}, status, store, nil)
+	return &dnsPeerActivator{
+		connMgr:   connMgr,
+		peerStore: store,
+		status:    status,
+		ctx:       context.Background(),
+	}, status, store
+}
+
+func TestDNSPeerActivator_NilSafe(t *testing.T) {
+	var a *dnsPeerActivator
+	a.ActivatePeersByIP(context.Background(), []netip.Addr{netip.MustParseAddr("100.64.0.1")})
+}
+
+// TestDNSPeerActivator_SkipsUnknownAndConnectedPeers verifies the steady-state
+// (warm) path adds no latency: already-connected and unknown addresses never
+// enter the wait loop.
+func TestDNSPeerActivator_SkipsUnknownAndConnectedPeers(t *testing.T) {
+	a, status, store := newTestDNSPeerActivator(t)
+
+	require.NoError(t, status.AddPeer("peerA", "a.netbird.cloud", "100.64.0.1", "fd00::1"))
+	require.NoError(t, status.UpdatePeerState(peer.State{PubKey: "peerA", ConnStatus: peer.StatusConnected}))
+	store.AddPeerConn("peerA", newTestPeerConn(t, "peerA"))
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	start := time.Now()
+	a.ActivatePeersByIP(ctx, []netip.Addr{
+		netip.MustParseAddr("100.64.0.1"),  // known, connected -> skipped
+		netip.MustParseAddr("fd00::1"),     // known via IPv6, connected -> skipped
+		netip.MustParseAddr("100.64.0.99"), // unknown -> skipped
+	})
+	require.Less(t, time.Since(start), time.Second, "no pending peer must mean no wait")
+}
+
+// TestDNSPeerActivator_WaitsForPendingPeerToConnect verifies the wait loop
+// returns as soon as a pending peer reports connected, well before the
+// per-query budget expires.
+func TestDNSPeerActivator_WaitsForPendingPeerToConnect(t *testing.T) {
+	a, status, store := newTestDNSPeerActivator(t)
+
+	require.NoError(t, status.AddPeer("peerA", "a.netbird.cloud", "100.64.0.1", ""))
+	store.AddPeerConn("peerA", newTestPeerConn(t, "peerA"))
+
+	go func() {
+		time.Sleep(150 * time.Millisecond)
+		_ = status.UpdatePeerState(peer.State{PubKey: "peerA", ConnStatus: peer.StatusConnected})
+	}()
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	start := time.Now()
+	a.ActivatePeersByIP(ctx, []netip.Addr{netip.MustParseAddr("100.64.0.1")})
+	elapsed := time.Since(start)
+
+	require.GreaterOrEqual(t, elapsed, 100*time.Millisecond, "must wait for the pending peer")
+	require.Less(t, elapsed, 5*time.Second, "must return on connect, not at the deadline")
+}
+
+// TestDNSPeerActivator_ReturnsAtBudgetWhenPeerStaysIdle verifies a peer that
+// never connects releases the DNS response at the per-query budget instead of
+// blocking it indefinitely.
+func TestDNSPeerActivator_ReturnsAtBudgetWhenPeerStaysIdle(t *testing.T) {
+	a, status, store := newTestDNSPeerActivator(t)
+
+	require.NoError(t, status.AddPeer("peerA", "a.netbird.cloud", "100.64.0.1", ""))
+	store.AddPeerConn("peerA", newTestPeerConn(t, "peerA"))
+
+	ctx, cancel := context.WithTimeout(context.Background(), 300*time.Millisecond)
+	defer cancel()
+
+	start := time.Now()
+	a.ActivatePeersByIP(ctx, []netip.Addr{netip.MustParseAddr("100.64.0.1")})
+	elapsed := time.Since(start)
+
+	require.GreaterOrEqual(t, elapsed, 250*time.Millisecond, "must wait out the budget for a pending peer")
+	require.Less(t, elapsed, 5*time.Second, "must not block past the budget")
+}
+
+// TestDNSPeerActivator_NoWaitWithoutPeerConn verifies a known-but-idle peer
+// with no connection object in the store is not waited on: there is nothing to
+// activate, so waiting could only ever time out.
+func TestDNSPeerActivator_NoWaitWithoutPeerConn(t *testing.T) {
+	a, status, _ := newTestDNSPeerActivator(t)
+
+	require.NoError(t, status.AddPeer("peerA", "a.netbird.cloud", "100.64.0.1", ""))
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	start := time.Now()
+	a.ActivatePeersByIP(ctx, []netip.Addr{netip.MustParseAddr("100.64.0.1")})
+	require.Less(t, time.Since(start), time.Second, "peer without a conn must not be waited on")
+}

client/internal/dnsfwd/forwarder.go

@@ -26,8 +26,23 @@ import (
 const errResolveFailed = "failed to resolve query for domain=%s: %v"
 const upstreamTimeout = 15 * time.Second
 
+// EDE info codes the forwarder emits on upstream failures so the querying
+// client can see the reason without inspecting this peer's logs. They live in
+// the RFC 8914 Private Use range (49152-65535); the Go resolver never exposes a
+// real upstream EDE here, so these cannot collide with a genuine code.
+const (
+	edeNetbirdUpstreamTimeout uint16 = 49152
+	edeNetbirdUpstreamFailure uint16 = 49153
+)
+
 type resolver interface {
 	LookupNetIP(ctx context.Context, network, host string) ([]netip.Addr, error)
+	LookupMX(ctx context.Context, name string) ([]*net.MX, error)
+	LookupTXT(ctx context.Context, name string) ([]string, error)
+	LookupNS(ctx context.Context, name string) ([]*net.NS, error)
+	LookupSRV(ctx context.Context, service, proto, name string) (string, []*net.SRV, error)
+	LookupCNAME(ctx context.Context, host string) (string, error)
+	LookupAddr(ctx context.Context, addr string) ([]string, error)
 }
 
 type firewaller interface {
@@ -201,12 +216,6 @@ func (f *DNSForwarder) handleDNSQuery(logger *log.Entry, w dns.ResponseWriter, q
 		qname, dns.TypeToString[question.Qtype], dns.ClassToString[question.Qclass])
 
 	resp := query.SetReply(query)
-	network := resutil.NetworkForQtype(question.Qtype)
-	if network == "" {
-		resp.Rcode = dns.RcodeNotImplemented
-		f.writeResponse(logger, w, resp, qname, startTime)
-		return
-	}
 
 	mostSpecificResId, matchingEntries := f.getMatchingEntries(strings.TrimSuffix(qname, "."))
 	if mostSpecificResId == "" {
@@ -218,9 +227,46 @@ func (f *DNSForwarder) handleDNSQuery(logger *log.Entry, w dns.ResponseWriter, q
 	ctx, cancel := context.WithTimeout(context.Background(), upstreamTimeout)
 	defer cancel()
 
+	reqHasEdns := query.IsEdns0() != nil
+
+	switch question.Qtype {
+	case dns.TypeA, dns.TypeAAAA:
+		f.handleAddressQuery(ctx, logger, w, resp, mostSpecificResId, matchingEntries, reqHasEdns, startTime)
+	case dns.TypeMX, dns.TypeTXT, dns.TypeNS, dns.TypeSRV, dns.TypeCNAME, dns.TypePTR:
+		f.handleRecordQuery(ctx, logger, w, resp, startTime)
+	default:
+		// The domain is routed here, so any other type is answered NODATA
+		// (NOERROR, empty answer) rather than falling back to a resolver that
+		// would poison the name with NXDOMAIN. The Extended DNS Error lets a
+		// client tell this capability-driven NODATA apart from an
+		// authoritative one. The OPT pseudo-record must not appear unless the
+		// query advertised EDNS0.
+		if reqHasEdns {
+			attachEDE(resp, dns.ExtendedErrorCodeNotSupported, "netbird forwarder: unsupported query type")
+		}
+		f.writeResponse(logger, w, resp, qname, startTime)
+	}
+}
+
+// handleAddressQuery resolves A/AAAA queries, programs the firewall sets and
+// resolved-IP state, and caches the answer for resilience on upstream failure.
+func (f *DNSForwarder) handleAddressQuery(
+	ctx context.Context,
+	logger *log.Entry,
+	w dns.ResponseWriter,
+	resp *dns.Msg,
+	mostSpecificResId route.ResID,
+	matchingEntries []*ForwarderEntry,
+	reqHasEdns bool,
+	startTime time.Time,
+) {
+	question := resp.Question[0]
+	qname := strings.ToLower(question.Name)
+
+	network := resutil.NetworkForQtype(question.Qtype)
 	result := resutil.LookupIP(ctx, f.resolver, network, qname, question.Qtype)
 	if result.Err != nil {
-		f.handleDNSError(ctx, logger, w, question, resp, qname, result, startTime)
+		f.handleDNSError(ctx, logger, w, question, resp, qname, result, reqHasEdns, startTime)
 		return
 	}
 
@@ -231,6 +277,25 @@ func (f *DNSForwarder) handleDNSQuery(logger *log.Entry, w dns.ResponseWriter, q
 	f.writeResponse(logger, w, resp, qname, startTime)
 }
 
+// handleRecordQuery resolves non-address record types (MX, TXT, NS, SRV,
+// CNAME, PTR) through the host resolver. Missing records are answered NODATA so
+// the routed name is never poisoned with NXDOMAIN.
+func (f *DNSForwarder) handleRecordQuery(
+	ctx context.Context,
+	logger *log.Entry,
+	w dns.ResponseWriter,
+	resp *dns.Msg,
+	startTime time.Time,
+) {
+	question := resp.Question[0]
+	qname := strings.ToLower(question.Name)
+
+	records, rcode := resutil.LookupRecords(ctx, f.resolver, qname, question.Qtype, f.ttl)
+	resp.Rcode = rcode
+	resp.Answer = append(resp.Answer, records...)
+	f.writeResponse(logger, w, resp, qname, startTime)
+}
+
 func (f *DNSForwarder) writeResponse(logger *log.Entry, w dns.ResponseWriter, resp *dns.Msg, qname string, startTime time.Time) {
 	if err := w.WriteMsg(resp); err != nil {
 		logger.Errorf("failed to write DNS response: %v", err)
@@ -333,6 +398,7 @@ func (f *DNSForwarder) handleDNSError(
 	resp *dns.Msg,
 	domain string,
 	result resutil.LookupResult,
+	reqHasEdns bool,
 	startTime time.Time,
 ) {
 	qType := question.Qtype
@@ -374,6 +440,10 @@ func (f *DNSForwarder) handleDNSError(
 		logger.Warnf(errResolveFailed, domain, result.Err)
 	}
 
+	if reqHasEdns {
+		attachEDE(resp, edeCodeFor(dnsErr), edeText(dnsErr))
+	}
+
 	f.writeResponse(logger, w, resp, domain, startTime)
 }
 
@@ -414,3 +484,33 @@ func (f *DNSForwarder) getMatchingEntries(domain string) (route.ResID, []*Forwar
 
 	return selectedResId, matches
 }
+
+// edeCodeFor maps an upstream lookup error to the NetBird EDE info code.
+func edeCodeFor(dnsErr *net.DNSError) uint16 {
+	if dnsErr != nil && dnsErr.IsTimeout {
+		return edeNetbirdUpstreamTimeout
+	}
+	return edeNetbirdUpstreamFailure
+}
+
+// edeText builds the EDE extra-text describing the class of upstream failure.
+// It deliberately omits the upstream server address, which may be an internal
+// resolver and is exposed to any client permitted to use the route; the full
+// detail stays in the forwarder's local log.
+func edeText(dnsErr *net.DNSError) string {
+	if dnsErr != nil && dnsErr.IsTimeout {
+		return "netbird forwarder: upstream timeout"
+	}
+	return "netbird forwarder: upstream failure"
+}
+
+// attachEDE adds an Extended DNS Error (RFC 8914) option to the response,
+// creating the OPT pseudo-record if the response does not already carry one.
+func attachEDE(resp *dns.Msg, code uint16, text string) {
+	opt := resp.IsEdns0()
+	if opt == nil {
+		resp.SetEdns0(dns.DefaultMsgSize, false)
+		opt = resp.IsEdns0()
+	}
+	opt.Option = append(opt.Option, &dns.EDNS0_EDE{InfoCode: code, ExtraText: text})
+}

client/internal/dnsfwd/forwarder_test.go

@@ -16,6 +16,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	firewall "github.com/netbirdio/netbird/client/firewall/manager"
+	"github.com/netbirdio/netbird/client/internal/dns/resutil"
 	"github.com/netbirdio/netbird/client/internal/dns/test"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/route"
@@ -132,6 +133,41 @@ func (m *MockResolver) LookupNetIP(ctx context.Context, network, host string) ([
 	return args.Get(0).([]netip.Addr), args.Error(1)
 }
 
+func (m *MockResolver) LookupMX(ctx context.Context, name string) ([]*net.MX, error) {
+	args := m.Called(ctx, name)
+	recs, _ := args.Get(0).([]*net.MX)
+	return recs, args.Error(1)
+}
+
+func (m *MockResolver) LookupTXT(ctx context.Context, name string) ([]string, error) {
+	args := m.Called(ctx, name)
+	recs, _ := args.Get(0).([]string)
+	return recs, args.Error(1)
+}
+
+func (m *MockResolver) LookupNS(ctx context.Context, name string) ([]*net.NS, error) {
+	args := m.Called(ctx, name)
+	recs, _ := args.Get(0).([]*net.NS)
+	return recs, args.Error(1)
+}
+
+func (m *MockResolver) LookupSRV(ctx context.Context, service, proto, name string) (string, []*net.SRV, error) {
+	args := m.Called(ctx, service, proto, name)
+	recs, _ := args.Get(1).([]*net.SRV)
+	return args.String(0), recs, args.Error(2)
+}
+
+func (m *MockResolver) LookupCNAME(ctx context.Context, host string) (string, error) {
+	args := m.Called(ctx, host)
+	return args.String(0), args.Error(1)
+}
+
+func (m *MockResolver) LookupAddr(ctx context.Context, addr string) ([]string, error) {
+	args := m.Called(ctx, addr)
+	recs, _ := args.Get(0).([]string)
+	return recs, args.Error(1)
+}
+
 func TestDNSForwarder_SubdomainAccessLogic(t *testing.T) {
 	tests := []struct {
 		name             string
@@ -544,12 +580,15 @@ func TestDNSForwarder_MultipleIPsInSingleUpdate(t *testing.T) {
 }
 
 func TestDNSForwarder_ResponseCodes(t *testing.T) {
+	// A type with no net.Resolver Lookup method (CAA) must answer NODATA
+	// (NOERROR, empty) rather than NXDOMAIN/NOTIMP to avoid poisoning the name.
 	tests := []struct {
 		name         string
 		queryType    uint16
 		queryDomain  string
 		configured   string
 		expectedCode int
+		expectEDE    bool
 		description  string
 	}{
 		{
@@ -561,28 +600,13 @@ func TestDNSForwarder_ResponseCodes(t *testing.T) {
 			description:  "RFC compliant REFUSED for unauthorized queries",
 		},
 		{
-			name:         "unsupported query type returns NOTIMP",
-			queryType:    dns.TypeMX,
+			name:         "unsupported query type returns NODATA",
+			queryType:    dns.TypeCAA,
 			queryDomain:  "example.com",
 			configured:   "example.com",
-			expectedCode: dns.RcodeNotImplemented,
-			description:  "RFC compliant NOTIMP for unsupported types",
-		},
-		{
-			name:         "CNAME query returns NOTIMP",
-			queryType:    dns.TypeCNAME,
-			queryDomain:  "example.com",
-			configured:   "example.com",
-			expectedCode: dns.RcodeNotImplemented,
-			description:  "CNAME queries not supported",
-		},
-		{
-			name:         "TXT query returns NOTIMP",
-			queryType:    dns.TypeTXT,
-			queryDomain:  "example.com",
-			configured:   "example.com",
-			expectedCode: dns.RcodeNotImplemented,
-			description:  "TXT queries not supported",
+			expectedCode: dns.RcodeSuccess,
+			expectEDE:    true,
+			description:  "Unsupported types answer NODATA, not NXDOMAIN/NOTIMP",
 		},
 	}
 
@@ -598,6 +622,7 @@ func TestDNSForwarder_ResponseCodes(t *testing.T) {
 
 			query := &dns.Msg{}
 			query.SetQuestion(dns.Fqdn(tt.queryDomain), tt.queryType)
+			query.SetEdns0(dns.DefaultMsgSize, false)
 
 			// Capture the written response
 			var writtenResp *dns.Msg
@@ -613,6 +638,288 @@ func TestDNSForwarder_ResponseCodes(t *testing.T) {
 			// Check the response written to the writer
 			require.NotNil(t, writtenResp, "Expected response to be written")
 			assert.Equal(t, tt.expectedCode, writtenResp.Rcode, tt.description)
+			assert.Empty(t, writtenResp.Answer, "Non-address response should carry no answers")
+
+			if tt.expectEDE {
+				require.NotNil(t, writtenResp.IsEdns0(), "EDNS0 client should get an OPT in the reply")
+				assert.True(t, hasEDE(writtenResp, dns.ExtendedErrorCodeNotSupported),
+					"unsupported type NODATA should carry EDE Not Supported")
+			}
+		})
+	}
+}
+
+func hasEDE(m *dns.Msg, code uint16) bool {
+	opt := m.IsEdns0()
+	if opt == nil {
+		return false
+	}
+	for _, o := range opt.Option {
+		if ede, ok := o.(*dns.EDNS0_EDE); ok && ede.InfoCode == code {
+			return true
+		}
+	}
+	return false
+}
+
+func TestDNSForwarder_RecordQueries(t *testing.T) {
+	notFound := &net.DNSError{IsNotFound: true, Name: "example.com"}
+
+	t.Run("MX records are forwarded", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "example.com")
+
+		mockResolver.On("LookupMX", mock.Anything, "example.com.").
+			Return([]*net.MX{{Host: "mail.example.com.", Pref: 10}}, nil).Once()
+
+		resp := runRecordQuery(t, forwarder, "example.com", dns.TypeMX)
+		require.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		require.Len(t, resp.Answer, 1)
+		mx, ok := resp.Answer[0].(*dns.MX)
+		require.True(t, ok, "answer should be an MX record")
+		assert.Equal(t, uint16(10), mx.Preference)
+		assert.Equal(t, "mail.example.com.", mx.Mx)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("missing MX is NODATA not NXDOMAIN", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "example.com")
+
+		// A not-found cannot prove the name is absent (it may exist with only
+		// other record types), so it must answer NODATA, never NXDOMAIN.
+		mockResolver.On("LookupMX", mock.Anything, "example.com.").
+			Return(nil, notFound).Once()
+
+		resp := runRecordQuery(t, forwarder, "example.com", dns.TypeMX)
+		assert.Equal(t, dns.RcodeSuccess, resp.Rcode, "missing record must be NODATA")
+		assert.Empty(t, resp.Answer)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("NS records are forwarded", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "example.com")
+
+		mockResolver.On("LookupNS", mock.Anything, "example.com.").
+			Return([]*net.NS{{Host: "ns1.example.com."}}, nil).Once()
+
+		resp := runRecordQuery(t, forwarder, "example.com", dns.TypeNS)
+		require.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		require.Len(t, resp.Answer, 1)
+		ns, ok := resp.Answer[0].(*dns.NS)
+		require.True(t, ok, "answer should be an NS record")
+		assert.Equal(t, "ns1.example.com.", ns.Ns)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("missing NS is NODATA", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "example.com")
+
+		mockResolver.On("LookupNS", mock.Anything, "example.com.").
+			Return(nil, notFound).Once()
+
+		resp := runRecordQuery(t, forwarder, "example.com", dns.TypeNS)
+		assert.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		assert.Empty(t, resp.Answer)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("SRV records are forwarded", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "_sip._tcp.example.com")
+
+		mockResolver.On("LookupSRV", mock.Anything, "", "", "_sip._tcp.example.com.").
+			Return("", []*net.SRV{{Target: "sip.example.com.", Port: 5060, Priority: 10, Weight: 5}}, nil).Once()
+
+		resp := runRecordQuery(t, forwarder, "_sip._tcp.example.com", dns.TypeSRV)
+		require.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		require.Len(t, resp.Answer, 1)
+		srv, ok := resp.Answer[0].(*dns.SRV)
+		require.True(t, ok, "answer should be an SRV record")
+		assert.Equal(t, "sip.example.com.", srv.Target)
+		assert.Equal(t, uint16(5060), srv.Port)
+		assert.Equal(t, uint16(10), srv.Priority)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("missing SRV is NODATA", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "_sip._tcp.example.com")
+
+		mockResolver.On("LookupSRV", mock.Anything, "", "", "_sip._tcp.example.com.").
+			Return("", nil, notFound).Once()
+
+		resp := runRecordQuery(t, forwarder, "_sip._tcp.example.com", dns.TypeSRV)
+		assert.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		assert.Empty(t, resp.Answer)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("TXT records are forwarded", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "example.com")
+
+		mockResolver.On("LookupTXT", mock.Anything, "example.com.").
+			Return([]string{"v=spf1 -all"}, nil).Once()
+
+		resp := runRecordQuery(t, forwarder, "example.com", dns.TypeTXT)
+		require.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		require.Len(t, resp.Answer, 1)
+		txt, ok := resp.Answer[0].(*dns.TXT)
+		require.True(t, ok, "answer should be a TXT record")
+		assert.Equal(t, []string{"v=spf1 -all"}, txt.Txt)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("CNAME record is forwarded", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "www.example.com")
+
+		mockResolver.On("LookupCNAME", mock.Anything, "www.example.com.").
+			Return("target.example.com.", nil).Once()
+
+		resp := runRecordQuery(t, forwarder, "www.example.com", dns.TypeCNAME)
+		require.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		require.Len(t, resp.Answer, 1)
+		cname, ok := resp.Answer[0].(*dns.CNAME)
+		require.True(t, ok, "answer should be a CNAME record")
+		assert.Equal(t, "target.example.com.", cname.Target)
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("CNAME equal to the name is NODATA", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "example.com")
+
+		// No CNAME exists: LookupCNAME echoes the queried name back.
+		mockResolver.On("LookupCNAME", mock.Anything, "example.com.").
+			Return("example.com.", nil).Once()
+
+		resp := runRecordQuery(t, forwarder, "example.com", dns.TypeCNAME)
+		assert.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		assert.Empty(t, resp.Answer, "self-referential CNAME means no CNAME record")
+		mockResolver.AssertExpectations(t)
+	})
+
+	t.Run("PTR record is forwarded", func(t *testing.T) {
+		mockResolver := &MockResolver{}
+		forwarder := newRecordTestForwarder(t, mockResolver, "*.in-addr.arpa")
+
+		// The reverse name is parsed back to the address LookupAddr expects.
+		mockResolver.On("LookupAddr", mock.Anything, "1.2.3.4").
+			Return([]string{"host.example.com."}, nil).Once()
+
+		resp := runRecordQuery(t, forwarder, "4.3.2.1.in-addr.arpa", dns.TypePTR)
+		require.Equal(t, dns.RcodeSuccess, resp.Rcode)
+		require.Len(t, resp.Answer, 1)
+		ptr, ok := resp.Answer[0].(*dns.PTR)
+		require.True(t, ok, "answer should be a PTR record")
+		assert.Equal(t, "host.example.com.", ptr.Ptr)
+		mockResolver.AssertExpectations(t)
+	})
+}
+
+func newRecordTestForwarder(t *testing.T, r resolver, configured string) *DNSForwarder {
+	t.Helper()
+	forwarder := NewDNSForwarder(netip.MustParseAddrPort("127.0.0.1:0"), 300, nil, &peer.Status{}, nil)
+	forwarder.resolver = r
+
+	d, err := domain.FromString(configured)
+	require.NoError(t, err)
+	forwarder.UpdateDomains([]*ForwarderEntry{{Domain: d, ResID: "test-res"}})
+	return forwarder
+}
+
+func runRecordQuery(t *testing.T, forwarder *DNSForwarder, qname string, qtype uint16) *dns.Msg {
+	t.Helper()
+	query := &dns.Msg{}
+	query.SetQuestion(dns.Fqdn(qname), qtype)
+
+	mockWriter := &test.MockResponseWriter{}
+	forwarder.handleDNSQuery(log.NewEntry(log.StandardLogger()), mockWriter, query, time.Now())
+
+	resp := mockWriter.GetLastResponse()
+	require.NotNil(t, resp, "expected response to be written")
+	return resp
+}
+
+func TestDNSForwarder_UpstreamFailureEDE(t *testing.T) {
+	tests := []struct {
+		name        string
+		lookupErr   error
+		reqEdns     bool
+		wantEDE     bool
+		wantCode    uint16
+		wantTextHas string
+	}{
+		{
+			name:        "timeout with edns0",
+			lookupErr:   &net.DNSError{Err: "i/o timeout", Server: "10.0.0.53:53", IsTimeout: true},
+			reqEdns:     true,
+			wantEDE:     true,
+			wantCode:    edeNetbirdUpstreamTimeout,
+			wantTextHas: "netbird forwarder: upstream timeout",
+		},
+		{
+			name:        "server failure with edns0",
+			lookupErr:   &net.DNSError{Err: "server misbehaving", Server: "10.0.0.53:53"},
+			reqEdns:     true,
+			wantEDE:     true,
+			wantCode:    edeNetbirdUpstreamFailure,
+			wantTextHas: "netbird forwarder: upstream failure",
+		},
+		{
+			name:      "no edns0 in request omits ede",
+			lookupErr: &net.DNSError{Err: "server misbehaving", Server: "10.0.0.53:53"},
+			reqEdns:   false,
+			wantEDE:   false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			mockResolver := &MockResolver{}
+			forwarder := NewDNSForwarder(netip.MustParseAddrPort("127.0.0.1:0"), 300, nil, &peer.Status{}, nil)
+			forwarder.resolver = mockResolver
+
+			d, err := domain.FromString("example.com")
+			require.NoError(t, err)
+			forwarder.UpdateDomains([]*ForwarderEntry{{Domain: d, ResID: "test-res"}})
+
+			mockResolver.On("LookupNetIP", mock.Anything, "ip4", "example.com.").
+				Return([]netip.Addr(nil), tt.lookupErr).Once()
+
+			query := &dns.Msg{}
+			query.SetQuestion("example.com.", dns.TypeA)
+			if tt.reqEdns {
+				query.SetEdns0(dns.DefaultMsgSize, false)
+			}
+
+			var writtenResp *dns.Msg
+			mockWriter := &test.MockResponseWriter{
+				WriteMsgFunc: func(m *dns.Msg) error {
+					writtenResp = m
+					return nil
+				},
+			}
+
+			forwarder.handleDNSQuery(log.NewEntry(log.StandardLogger()), mockWriter, query, time.Now())
+			mockResolver.AssertExpectations(t)
+
+			require.NotNil(t, writtenResp, "expected a response")
+			assert.Equal(t, dns.RcodeServerFailure, writtenResp.Rcode, "upstream failure must be SERVFAIL")
+
+			ede, ok := resutil.ExtractEDE(writtenResp)
+			if !tt.wantEDE {
+				assert.False(t, ok, "response must not carry EDE")
+				return
+			}
+			require.True(t, ok, "response must carry EDE")
+			assert.Equal(t, tt.wantCode, ede.InfoCode, "EDE info code")
+			assert.Contains(t, ede.ExtraText, tt.wantTextHas, "EDE extra-text")
+			assert.NotContains(t, ede.ExtraText, "10.0.0.53", "must not leak upstream server address")
 		})
 	}
 }

client/internal/dnsfwd/manager.go

@@ -101,7 +101,7 @@ func (m *Manager) Start(fwdEntries []*ForwarderEntry) error {
 	m.dnsForwarder = NewDNSForwarder(listenAddress, dnsTTL, m.firewall, m.statusRecorder, m.wgIface)
 
 	go func() {
-		if err := m.dnsForwarder.Listen(fwdEntries); err != nil {
+		if err := m.dnsForwarder.Listen(fwdEntries); err != nil { //nolint:staticcheck
 			// todo handle close error if it is exists
 			log.Errorf("failed to start DNS forwarder, err: %v", err)
 		}

client/internal/ebpf/ebpf/src/dns_fwd.c

@@ -52,11 +52,14 @@ int xdp_dns_fwd(struct iphdr  *ip, struct udphdr *udp) {
 
     if (udp->dest == GENERAL_DNS_PORT && ip->daddr == dns_ip) {
         udp->dest = dns_port;
+        // Clear the now-stale checksum; zero means "not computed" for IPv4.
+        udp->check = 0;
         return XDP_PASS;
     }
 
     if (udp->source == dns_port && ip->saddr == dns_ip) {
         udp->source = GENERAL_DNS_PORT;
+        udp->check = 0;
         return XDP_PASS;
     }
 

client/internal/ebpf/ebpf/src/wg_proxy.c

@@ -50,5 +50,11 @@ int xdp_wg_proxy(struct iphdr  *ip, struct udphdr *udp) {
     __be16 new_dst_port = htons(proxy_port);
     udp->dest = new_dst_port;
     udp->source = new_src_port;
+
+    // The ports are covered by the UDP checksum. This is an IPv4 loopback hop
+    // and the payload is already integrity-protected, so clear the checksum (a
+    // zero UDP checksum means "not computed" for IPv4) rather than leave a
+    // stale value the kernel would drop as UDP_CSUM.
+    udp->check = 0;
 	return XDP_PASS;
 }

client/internal/engine_authsession.go

@@ -0,0 +1,108 @@
+package internal
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	"google.golang.org/protobuf/types/known/timestamppb"
+
+	"github.com/netbirdio/netbird/client/internal/auth/sessionwatch"
+	cProto "github.com/netbirdio/netbird/client/proto"
+	"github.com/netbirdio/netbird/client/system"
+)
+
+// ApplySessionDeadline propagates the absolute SSO session deadline carried on
+// LoginResponse / SyncResponse to both the watcher (for the edge-triggered
+// warning) and the status recorder (for the SubscribeStatus / Status RPC
+// snapshot the UI consumes).
+//
+// The wire field is 3-state:
+//   - nil                        → snapshot carries no info; keep the
+//     previously-anchored deadline (no-op)
+//   - explicit zero (s=0, n=0)   → peer is not SSO-registered or expiry is
+//     disabled; clear both sinks
+//   - valid timestamp            → new deadline; arm watcher, expose on
+//     status recorder
+//
+// Deadline sanity-checks live in sessionwatch.Watcher.Update. Any rejected
+// value is treated as a clear on both sinks: the alternative — leaving the
+// previously-known deadline in place — risks the UI confidently displaying
+// a stale "expires in X" while the server has actually invalidated it.
+func (e *Engine) ApplySessionDeadline(ts *timestamppb.Timestamp) {
+	if ts == nil {
+		return
+	}
+	var deadline time.Time
+	// Explicit zero (seconds=0 AND nanos=0) is the sentinel for "disabled".
+	// Everything else flows through Watcher.Update, whose sanity-checks
+	// reject out-of-range / pre-epoch / far-future / too-stale values and
+	// clear on rejection.
+	if ts.GetSeconds() != 0 || ts.GetNanos() != 0 {
+		deadline = ts.AsTime().UTC()
+	}
+	if e.sessionWatcher == nil {
+		return
+	}
+	// Watcher.Update owns the propagation to the status recorder (the
+	// SubscribeStatus / Status snapshot the UI reads): a set writes the
+	// deadline, a clear or a sanity-check rejection writes the zero value.
+	// Keeping a single writer is what stops the recorder from drifting out
+	// of sync with the warning timers.
+	if err := e.sessionWatcher.Update(deadline); err != nil {
+		log.Errorf("auth session deadline rejected: %v, clearing", err)
+		e.statusRecorder.PublishEvent(
+			cProto.SystemEvent_ERROR,
+			cProto.SystemEvent_AUTHENTICATION,
+			"session deadline rejected",
+			"",
+			map[string]string{sessionwatch.MetaSessionDeadlineRejected: err.Error()},
+		)
+	}
+}
+
+// DismissSessionWarning records the user's "Dismiss" click on the
+// T-WarningLead interactive notification and suppresses the upcoming
+// T-FinalWarningLead fallback for the current deadline. No-op when the
+// watcher is not running or holds no deadline.
+func (e *Engine) DismissSessionWarning() {
+	if e.sessionWatcher == nil {
+		return
+	}
+	e.sessionWatcher.Dismiss()
+}
+
+// ExtendAuthSession asks the management server to refresh the SSO session
+// expiry deadline using the supplied JWT, then mirrors the new deadline into
+// the daemon's state. The tunnel is untouched; no resync, no reconnect.
+//
+// Returns the new absolute UTC deadline (or zero time when the server
+// reports the peer is not eligible for extension).
+func (e *Engine) ExtendAuthSession(ctx context.Context, jwtToken string) (time.Time, error) {
+	if jwtToken == "" {
+		return time.Time{}, errors.New("jwt token is required")
+	}
+	if e.mgmClient == nil {
+		return time.Time{}, errors.New("management client is not initialised")
+	}
+
+	info, err := system.GetInfoWithChecks(ctx, e.checks)
+	if err != nil {
+		log.Warnf("failed to collect system info for session extend: %v", err)
+		info = system.GetInfo(ctx)
+	}
+
+	resp, err := e.mgmClient.ExtendAuthSession(info, jwtToken)
+	if err != nil {
+		return time.Time{}, fmt.Errorf("extend auth session on management: %w", err)
+	}
+
+	e.ApplySessionDeadline(resp.GetSessionExpiresAt())
+
+	if resp.GetSessionExpiresAt().IsValid() {
+		return resp.GetSessionExpiresAt().AsTime().UTC(), nil
+	}
+	return time.Time{}, nil
+}

client/internal/engine_lazy_exclude_test.go

@@ -0,0 +1,87 @@
+package internal
+
+import (
+	"net/netip"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	firewallManager "github.com/netbirdio/netbird/client/firewall/manager"
+	"github.com/netbirdio/netbird/client/internal/peer"
+	"github.com/netbirdio/netbird/client/internal/peerstore"
+	mgmProto "github.com/netbirdio/netbird/shared/management/proto"
+)
+
+func TestPrefixesContain(t *testing.T) {
+	tests := []struct {
+		name     string
+		prefixes []string
+		addr     string
+		want     bool
+	}{
+		{name: "own overlay /32 matches", prefixes: []string{"100.110.8.145/32"}, addr: "100.110.8.145", want: true},
+		{name: "addr inside routed subnet", prefixes: []string{"10.121.0.0/16"}, addr: "10.121.208.4", want: true},
+		{name: "addr outside subnet", prefixes: []string{"10.121.0.0/16"}, addr: "10.122.0.1", want: false},
+		{name: "different /32", prefixes: []string{"100.110.8.145/32"}, addr: "100.110.8.146", want: false},
+		{name: "ipv6 /128 matches", prefixes: []string{"fd00::1/128"}, addr: "fd00::1", want: true},
+		{name: "no prefixes", prefixes: nil, addr: "10.121.208.4", want: false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			prefixes := make([]netip.Prefix, 0, len(tt.prefixes))
+			for _, p := range tt.prefixes {
+				prefixes = append(prefixes, netip.MustParsePrefix(p))
+			}
+			require.Equal(t, tt.want, prefixesContain(prefixes, netip.MustParseAddr(tt.addr)))
+		})
+	}
+}
+
+// TestToExcludedLazyPeers_ForwardTarget guards a regression: the forward-target
+// peer (the peer routing a ForwardRule.TranslatedAddress) must be excluded from
+// lazy connections, matched via the peer's already-parsed AllowedIPs.
+func TestToExcludedLazyPeers_ForwardTarget(t *testing.T) {
+	const targetPeerKey = "cccccccccccccccccccccccccccccccccccccccccc0="
+	const otherPeerKey = "dddddddddddddddddddddddddddddddddddddddddd0="
+
+	store := peerstore.NewConnStore()
+	store.AddPeerConn(targetPeerKey, newTestConn(t, targetPeerKey, "100.110.8.145/32"))
+	store.AddPeerConn(otherPeerKey, newTestConn(t, otherPeerKey, "100.110.9.10/32"))
+
+	e := &Engine{peerStore: store}
+
+	peers := []*mgmProto.RemotePeerConfig{
+		{WgPubKey: targetPeerKey, AllowedIps: []string{"100.110.8.145/32"}},
+		{WgPubKey: otherPeerKey, AllowedIps: []string{"100.110.9.10/32"}},
+	}
+	rules := []firewallManager.ForwardRule{
+		{TranslatedAddress: netip.MustParseAddr("100.110.8.145")},
+	}
+
+	excluded := e.toExcludedLazyPeers(rules, peers)
+
+	require.True(t, excluded[targetPeerKey], "forward-target peer must be excluded from lazy connections")
+	require.False(t, excluded[otherPeerKey], "non-target peer must not be excluded")
+	require.Len(t, excluded, 1)
+}
+
+func TestToExcludedLazyPeers_NoRules(t *testing.T) {
+	e := &Engine{peerStore: peerstore.NewConnStore()}
+
+	peers := []*mgmProto.RemotePeerConfig{
+		{WgPubKey: "peer-a", AllowedIps: []string{"100.110.8.145/32"}},
+	}
+
+	require.Empty(t, e.toExcludedLazyPeers(nil, peers))
+}
+
+func newTestConn(t *testing.T, key, allowedIP string) *peer.Conn {
+	t.Helper()
+	conn, err := peer.NewConn(peer.ConnConfig{
+		Key:      key,
+		WgConfig: peer.WgConfig{AllowedIps: []netip.Prefix{netip.MustParsePrefix(allowedIP)}},
+	}, peer.ServiceDependencies{})
+	require.NoError(t, err)
+	return conn
+}

client/internal/engine_privileged_test.go

@@ -0,0 +1,565 @@
+//go:build privileged
+
+package internal
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"go.uber.org/mock/gomock"
+	"github.com/google/uuid"
+	log "github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/otel"
+	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/keepalive"
+
+	"github.com/netbirdio/netbird/client/iface"
+	"github.com/netbirdio/netbird/client/iface/device"
+	"github.com/netbirdio/netbird/client/iface/wgaddr"
+	"github.com/netbirdio/netbird/client/internal/dns"
+	"github.com/netbirdio/netbird/client/internal/peer"
+	nbssh "github.com/netbirdio/netbird/client/ssh"
+	"github.com/netbirdio/netbird/client/system"
+	nbdns "github.com/netbirdio/netbird/dns"
+	"github.com/netbirdio/netbird/management/internals/controllers/network_map/controller"
+	"github.com/netbirdio/netbird/management/internals/controllers/network_map/update_channel"
+	"github.com/netbirdio/netbird/management/internals/modules/peers"
+	"github.com/netbirdio/netbird/management/internals/modules/peers/ephemeral/manager"
+	"github.com/netbirdio/netbird/management/internals/server/config"
+	nbgrpc "github.com/netbirdio/netbird/management/internals/shared/grpc"
+	"github.com/netbirdio/netbird/management/server"
+	"github.com/netbirdio/netbird/management/server/activity"
+	nbcache "github.com/netbirdio/netbird/management/server/cache"
+	"github.com/netbirdio/netbird/management/server/groups"
+	"github.com/netbirdio/netbird/management/server/integrations/integrated_validator/validator"
+	"github.com/netbirdio/netbird/management/server/integrations/port_forwarding"
+	"github.com/netbirdio/netbird/management/server/job"
+	"github.com/netbirdio/netbird/management/server/permissions"
+	"github.com/netbirdio/netbird/management/server/settings"
+	"github.com/netbirdio/netbird/management/server/store"
+	"github.com/netbirdio/netbird/management/server/telemetry"
+	"github.com/netbirdio/netbird/management/server/types"
+	mgmt "github.com/netbirdio/netbird/shared/management/client"
+	mgmtProto "github.com/netbirdio/netbird/shared/management/proto"
+	relayClient "github.com/netbirdio/netbird/shared/relay/client"
+	signal "github.com/netbirdio/netbird/shared/signal/client"
+	"github.com/netbirdio/netbird/shared/signal/proto"
+	signalServer "github.com/netbirdio/netbird/signal/server"
+	"github.com/netbirdio/netbird/util"
+)
+
+func TestEngine_SSH(t *testing.T) {
+	key, err := wgtypes.GeneratePrivateKey()
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+
+	sshKey, err := nbssh.GeneratePrivateKey(nbssh.ED25519)
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+
+	ctx, cancel := context.WithCancel(CtxInitState(context.Background()))
+	defer cancel()
+
+	relayMgr := relayClient.NewManager(ctx, nil, key.PublicKey().String(), iface.DefaultMTU)
+	engine := NewEngine(
+		ctx, cancel,
+		&EngineConfig{
+			WgIfaceName:      "utun101",
+			WgAddr:           wgaddr.MustParseWGAddress("100.64.0.1/24"),
+			WgPrivateKey:     key,
+			WgPort:           33100,
+			ServerSSHAllowed: true,
+			MTU:              iface.DefaultMTU,
+			SSHKey:           sshKey,
+		},
+		EngineServices{
+			SignalClient:   &signal.MockClient{},
+			MgmClient:      &mgmt.MockClient{},
+			RelayManager:   relayMgr,
+			StatusRecorder: peer.NewRecorder("https://mgm"),
+		},
+		MobileDependency{},
+	)
+
+	engine.dnsServer = &dns.MockServer{
+		UpdateDNSServerFunc: func(serial uint64, update nbdns.Config) error { return nil },
+	}
+
+	err = engine.Start(nil, nil)
+	require.NoError(t, err)
+
+	defer func() {
+		err := engine.Stop()
+		if err != nil {
+			return
+		}
+	}()
+
+	peerWithSSH := &mgmtProto.RemotePeerConfig{
+		WgPubKey:   "MNHf3Ma6z6mdLbriAJbqhX7+nM/B71lgw2+91q3LfhU=",
+		AllowedIps: []string{"100.64.0.21/24"},
+		SshConfig: &mgmtProto.SSHConfig{
+			SshPubKey: []byte("ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIFATYCqaQw/9id1Qkq3n16JYhDhXraI6Pc1fgB8ynEfQ"),
+		},
+	}
+
+	// SSH server is not enabled so SSH config of a remote peer should be ignored
+	networkMap := &mgmtProto.NetworkMap{
+		Serial:             6,
+		PeerConfig:         nil,
+		RemotePeers:        []*mgmtProto.RemotePeerConfig{peerWithSSH},
+		RemotePeersIsEmpty: false,
+	}
+
+	err = engine.updateNetworkMap(networkMap)
+	require.NoError(t, err)
+
+	assert.Nil(t, engine.sshServer)
+
+	// SSH server is enabled, therefore SSH config should be applied
+	networkMap = &mgmtProto.NetworkMap{
+		Serial: 7,
+		PeerConfig: &mgmtProto.PeerConfig{Address: "100.64.0.1/24",
+			SshConfig: &mgmtProto.SSHConfig{
+				SshEnabled: true,
+				JwtConfig: &mgmtProto.JWTConfig{
+					Issuer:       "test-issuer",
+					Audience:     "test-audience",
+					KeysLocation: "test-keys",
+					MaxTokenAge:  3600,
+				},
+			}},
+		RemotePeers:        []*mgmtProto.RemotePeerConfig{peerWithSSH},
+		RemotePeersIsEmpty: false,
+	}
+
+	err = engine.updateNetworkMap(networkMap)
+	require.NoError(t, err)
+
+	time.Sleep(250 * time.Millisecond)
+	assert.NotNil(t, engine.sshServer)
+
+	// now remove peer
+	networkMap = &mgmtProto.NetworkMap{
+		Serial:             8,
+		RemotePeers:        []*mgmtProto.RemotePeerConfig{},
+		RemotePeersIsEmpty: false,
+	}
+
+	err = engine.updateNetworkMap(networkMap)
+	require.NoError(t, err)
+
+	// time.Sleep(250 * time.Millisecond)
+	assert.NotNil(t, engine.sshServer)
+
+	// now disable SSH server
+	networkMap = &mgmtProto.NetworkMap{
+		Serial: 9,
+		PeerConfig: &mgmtProto.PeerConfig{Address: "100.64.0.1/24",
+			SshConfig: &mgmtProto.SSHConfig{SshEnabled: false}},
+		RemotePeers:        []*mgmtProto.RemotePeerConfig{peerWithSSH},
+		RemotePeersIsEmpty: false,
+	}
+
+	err = engine.updateNetworkMap(networkMap)
+	require.NoError(t, err)
+
+	assert.Nil(t, engine.sshServer)
+}
+
+func TestEngine_Sync(t *testing.T) {
+	key, err := wgtypes.GeneratePrivateKey()
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+
+	ctx, cancel := context.WithCancel(CtxInitState(context.Background()))
+	defer cancel()
+
+	// feed updates to Engine via mocked Management client
+	updates := make(chan *mgmtProto.SyncResponse)
+	defer close(updates)
+	syncFunc := func(ctx context.Context, info *system.Info, msgHandler func(msg *mgmtProto.SyncResponse) error) error {
+		for msg := range updates {
+			err := msgHandler(msg)
+			if err != nil {
+				t.Fatal(err)
+			}
+		}
+		return nil
+	}
+	relayMgr := relayClient.NewManager(ctx, nil, key.PublicKey().String(), iface.DefaultMTU)
+	engine := NewEngine(ctx, cancel, &EngineConfig{
+		WgIfaceName:  "utun103",
+		WgAddr:       wgaddr.MustParseWGAddress("100.64.0.1/24"),
+		WgPrivateKey: key,
+		WgPort:       33100,
+		MTU:          iface.DefaultMTU,
+	}, EngineServices{
+		SignalClient:   &signal.MockClient{},
+		MgmClient:      &mgmt.MockClient{SyncFunc: syncFunc},
+		RelayManager:   relayMgr,
+		StatusRecorder: peer.NewRecorder("https://mgm"),
+	}, MobileDependency{})
+	engine.ctx = ctx
+
+	engine.dnsServer = &dns.MockServer{
+		UpdateDNSServerFunc: func(serial uint64, update nbdns.Config) error { return nil },
+	}
+
+	defer func() {
+		err := engine.Stop()
+		if err != nil {
+			return
+		}
+	}()
+
+	err = engine.Start(nil, nil)
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+
+	peer1 := &mgmtProto.RemotePeerConfig{
+		WgPubKey:   "RRHf3Ma6z6mdLbriAJbqhX7+nM/B71lgw2+91q3LfhU=",
+		AllowedIps: []string{"100.64.0.10/24"},
+	}
+	peer2 := &mgmtProto.RemotePeerConfig{
+		WgPubKey:   "LLHf3Ma6z6mdLbriAJbqhX9+nM/B71lgw2+91q3LlhU=",
+		AllowedIps: []string{"100.64.0.11/24"},
+	}
+	peer3 := &mgmtProto.RemotePeerConfig{
+		WgPubKey:   "GGHf3Ma6z6mdLbriAJbqhX9+nM/B71lgw2+91q3LlhU=",
+		AllowedIps: []string{"100.64.0.12/24"},
+	}
+	// 1st update with just 1 peer and serial larger than the current serial of the engine => apply update
+	updates <- &mgmtProto.SyncResponse{
+		NetworkMap: &mgmtProto.NetworkMap{
+			Serial:             10,
+			PeerConfig:         nil,
+			RemotePeers:        []*mgmtProto.RemotePeerConfig{peer1, peer2, peer3},
+			RemotePeersIsEmpty: false,
+		},
+	}
+
+	timeout := time.After(time.Second * 2)
+	for {
+		select {
+		case <-timeout:
+			t.Fatalf("timeout while waiting for test to finish")
+			return
+		default:
+		}
+
+		if getPeers(engine) == 3 && engine.networkSerial == 10 {
+			break
+		}
+	}
+}
+
+func TestEngine_MultiplePeers(t *testing.T) {
+	// log.SetLevel(log.DebugLevel)
+
+	ctx, cancel := context.WithCancel(CtxInitState(context.Background()))
+	defer cancel()
+
+	sigServer, signalAddr, err := startSignal(t)
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+	defer sigServer.Stop()
+	mgmtServer, mgmtAddr, err := startManagement(t, t.TempDir(), "../testdata/store.sql")
+	if err != nil {
+		t.Fatal(err)
+		return
+	}
+	defer mgmtServer.GracefulStop()
+
+	setupKey := "A2C8E62B-38F5-4553-B31E-DD66C696CEBB"
+
+	mu := sync.Mutex{}
+	engines := []*Engine{}
+	numPeers := 10
+	wg := sync.WaitGroup{}
+	wg.Add(numPeers)
+	// create and start peers
+	for i := 0; i < numPeers; i++ {
+		j := i
+		go func() {
+			engine, err := createEngine(ctx, cancel, setupKey, j, mgmtAddr, signalAddr)
+			if err != nil {
+				wg.Done()
+				t.Errorf("unable to create the engine for peer %d with error %v", j, err)
+				return
+			}
+			engine.dnsServer = &dns.MockServer{}
+			mu.Lock()
+			defer mu.Unlock()
+			guid := fmt.Sprintf("{%s}", uuid.New().String())
+			device.CustomWindowsGUIDString = strings.ToLower(guid)
+			err = engine.Start(nil, nil)
+			if err != nil {
+				t.Errorf("unable to start engine for peer %d with error %v", j, err)
+				wg.Done()
+				return
+			}
+			engines = append(engines, engine)
+			wg.Done()
+		}()
+	}
+
+	// wait until all have been created and started
+	wg.Wait()
+	if len(engines) != numPeers {
+		t.Fatal("not all peers were started")
+	}
+	// check whether all the peer have expected peers connected
+
+	expectedConnected := numPeers * (numPeers - 1)
+
+	// adjust according to timeouts
+	timeout := 50 * time.Second
+	timeoutChan := time.After(timeout)
+	ticker := time.NewTicker(time.Second)
+	defer ticker.Stop()
+loop:
+	for {
+		select {
+		case <-timeoutChan:
+			t.Fatalf("waiting for expected connections timeout after %s", timeout.String())
+			break loop
+		case <-ticker.C:
+			totalConnected := 0
+			for _, engine := range engines {
+				totalConnected += getConnectedPeers(engine)
+			}
+			if totalConnected == expectedConnected {
+				log.Infof("total connected=%d", totalConnected)
+				break loop
+			}
+			log.Infof("total connected=%d", totalConnected)
+		}
+	}
+	// cleanup test
+	for n, peerEngine := range engines {
+		t.Logf("stopping peer with interface %s from multipeer test, loopIndex %d", peerEngine.wgInterface.Name(), n)
+		errStop := peerEngine.mgmClient.Close()
+		if errStop != nil {
+			log.Infoln("got error trying to close management clients from engine: ", errStop)
+		}
+		errStop = peerEngine.Stop()
+		if errStop != nil {
+			log.Infoln("got error trying to close testing peers engine: ", errStop)
+		}
+	}
+}
+
+var (
+	kaep = keepalive.EnforcementPolicy{
+		MinTime:             15 * time.Second,
+		PermitWithoutStream: true,
+	}
+
+	kasp = keepalive.ServerParameters{
+		MaxConnectionIdle:     15 * time.Second,
+		MaxConnectionAgeGrace: 5 * time.Second,
+		Time:                  5 * time.Second,
+		Timeout:               2 * time.Second,
+	}
+)
+
+func createEngine(ctx context.Context, cancel context.CancelFunc, setupKey string, i int, mgmtAddr string, signalAddr string) (*Engine, error) {
+	key, err := wgtypes.GeneratePrivateKey()
+	if err != nil {
+		return nil, err
+	}
+	mgmtClient, err := mgmt.NewClient(ctx, mgmtAddr, key, false)
+	if err != nil {
+		return nil, err
+	}
+	signalClient, err := signal.NewClient(ctx, signalAddr, key, false)
+	if err != nil {
+		return nil, err
+	}
+
+	info := system.GetInfo(ctx)
+	resp, err := mgmtClient.Register(setupKey, "", info, nil, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var ifaceName string
+	if runtime.GOOS == "darwin" {
+		ifaceName = fmt.Sprintf("utun1%d", i)
+	} else {
+		ifaceName = fmt.Sprintf("wt%d", i)
+	}
+
+	wgPort := 33100 + i
+	conf := &EngineConfig{
+		WgIfaceName:  ifaceName,
+		WgAddr:       wgaddr.MustParseWGAddress(resp.PeerConfig.Address),
+		WgPrivateKey: key,
+		WgPort:       wgPort,
+		MTU:          iface.DefaultMTU,
+	}
+
+	relayMgr := relayClient.NewManager(ctx, nil, key.PublicKey().String(), iface.DefaultMTU)
+	e, err := NewEngine(ctx, cancel, conf, EngineServices{
+		SignalClient:   signalClient,
+		MgmClient:      mgmtClient,
+		RelayManager:   relayMgr,
+		StatusRecorder: peer.NewRecorder("https://mgm"),
+	}, MobileDependency{}), nil
+	e.ctx = ctx
+	return e, err
+}
+
+func startSignal(t *testing.T) (*grpc.Server, string, error) {
+	t.Helper()
+
+	s := grpc.NewServer(grpc.KeepaliveEnforcementPolicy(kaep), grpc.KeepaliveParams(kasp))
+
+	lis, err := net.Listen("tcp", "localhost:0")
+	if err != nil {
+		log.Fatalf("failed to listen: %v", err)
+	}
+
+	srv, err := signalServer.NewServer(context.Background(), otel.Meter(""))
+	require.NoError(t, err)
+	proto.RegisterSignalExchangeServer(s, srv)
+
+	go func() {
+		if err = s.Serve(lis); err != nil {
+			log.Fatalf("failed to serve: %v", err)
+		}
+	}()
+
+	return s, lis.Addr().String(), nil
+}
+
+func startManagement(t *testing.T, dataDir, testFile string) (*grpc.Server, string, error) {
+	t.Helper()
+
+	config := &config.Config{
+		Stuns:      []*config.Host{},
+		TURNConfig: &config.TURNConfig{},
+		Relay: &config.Relay{
+			Addresses:      []string{"127.0.0.1:1234"},
+			CredentialsTTL: util.Duration{Duration: time.Hour},
+			Secret:         "222222222222222222",
+		},
+		Signal: &config.Host{
+			Proto: "http",
+			URI:   "localhost:10000",
+		},
+		Datadir:    dataDir,
+		HttpConfig: nil,
+	}
+
+	lis, err := net.Listen("tcp", "localhost:0")
+	if err != nil {
+		return nil, "", err
+	}
+	s := grpc.NewServer(grpc.KeepaliveEnforcementPolicy(kaep), grpc.KeepaliveParams(kasp))
+
+	store, cleanUp, err := store.NewTestStoreFromSQL(context.Background(), testFile, config.Datadir)
+	if err != nil {
+		return nil, "", err
+	}
+	t.Cleanup(cleanUp)
+
+	eventStore := &activity.InMemoryEventStore{}
+	if err != nil {
+		return nil, "", err
+	}
+
+	permissionsManager := permissions.NewManager(store)
+	peersManager := peers.NewManager(store, permissionsManager)
+	jobManager := job.NewJobManager(nil, store, peersManager)
+
+	cacheStore, err := nbcache.NewStore(context.Background(), 100*time.Millisecond, 300*time.Millisecond, 100)
+	if err != nil {
+		return nil, "", err
+	}
+
+	ia, _ := validator.NewIntegratedValidator(context.Background(), peersManager, nil, eventStore, cacheStore)
+
+	metrics, err := telemetry.NewDefaultAppMetrics(context.Background())
+	require.NoError(t, err)
+
+	ctrl := gomock.NewController(t)
+	t.Cleanup(ctrl.Finish)
+	settingsMockManager := settings.NewMockManager(ctrl)
+	settingsMockManager.EXPECT().
+		GetSettings(gomock.Any(), gomock.Any(), gomock.Any()).
+		Return(&types.Settings{}, nil).
+		AnyTimes()
+	settingsMockManager.EXPECT().
+		GetExtraSettings(gomock.Any(), gomock.Any()).
+		Return(&types.ExtraSettings{}, nil).
+		AnyTimes()
+
+	groupsManager := groups.NewManagerMock()
+
+	updateManager := update_channel.NewPeersUpdateManager(metrics)
+	requestBuffer := server.NewAccountRequestBuffer(context.Background(), store)
+	networkMapController := controller.NewController(context.Background(), store, metrics, updateManager, requestBuffer, server.MockIntegratedValidator{}, settingsMockManager, "netbird.selfhosted", port_forwarding.NewControllerMock(), manager.NewEphemeralManager(store, peersManager), config)
+	accountManager, err := server.BuildManager(context.Background(), config, store, networkMapController, jobManager, nil, "", eventStore, nil, false, ia, metrics, port_forwarding.NewControllerMock(), settingsMockManager, permissionsManager, false, cacheStore)
+	if err != nil {
+		return nil, "", err
+	}
+
+	secretsManager, err := nbgrpc.NewTimeBasedAuthSecretsManager(updateManager, config.TURNConfig, config.Relay, settingsMockManager, groupsManager)
+	if err != nil {
+		return nil, "", err
+	}
+	mgmtServer, err := nbgrpc.NewServer(config, accountManager, settingsMockManager, jobManager, secretsManager, nil, nil, &server.MockIntegratedValidator{}, networkMapController, nil, nil)
+	if err != nil {
+		return nil, "", err
+	}
+	mgmtProto.RegisterManagementServiceServer(s, mgmtServer)
+	go func() {
+		if err = s.Serve(lis); err != nil {
+			log.Fatalf("failed to serve: %v", err)
+		}
+	}()
+
+	return s, lis.Addr().String(), nil
+}
+
+// getConnectedPeers returns a connection Status or nil if peer connection wasn't found
+func getConnectedPeers(e *Engine) int {
+	e.syncMsgMux.Lock()
+	defer e.syncMsgMux.Unlock()
+	i := 0
+	for _, id := range e.peerStore.PeersPubKey() {
+		conn, _ := e.peerStore.PeerConn(id)
+		if conn.IsConnected() {
+			i++
+		}
+	}
+	return i
+}
+
+func getPeers(e *Engine) int {
+	e.syncMsgMux.Lock()
+	defer e.syncMsgMux.Unlock()
+
+	return len(e.peerStore.PeersPubKey())
+}

client/internal/engine_session_deadline_test.go

@@ -0,0 +1,88 @@
+package internal
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+	"google.golang.org/protobuf/types/known/timestamppb"
+
+	"github.com/netbirdio/netbird/client/internal/auth/sessionwatch"
+	"github.com/netbirdio/netbird/client/internal/peer"
+)
+
+// TestApplySessionDeadline_ThreeState pins down the 3-state semantics of the
+// wire field carried on LoginResponse / SyncResponse:
+//
+//   - nil pointer            → no info; previously-anchored deadline survives
+//   - explicit zero value    → "expiry disabled" sentinel; both sinks cleared
+//   - valid future timestamp → new deadline propagated to both sinks
+func TestApplySessionDeadline_ThreeState(t *testing.T) {
+	newEngine := func() *Engine {
+		recorder := peer.NewRecorder("")
+		return &Engine{
+			statusRecorder: recorder,
+			sessionWatcher: sessionwatch.New(recorder),
+		}
+	}
+
+	t.Run("valid timestamp sets deadline on both sinks", func(t *testing.T) {
+		e := newEngine()
+		deadline := time.Now().Add(time.Hour).UTC().Truncate(time.Second)
+
+		e.ApplySessionDeadline(timestamppb.New(deadline))
+
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().Equal(deadline),
+			"status recorder should hold the new deadline")
+	})
+
+	t.Run("nil is a no-op and preserves previous deadline", func(t *testing.T) {
+		e := newEngine()
+		seeded := time.Now().Add(time.Hour).UTC().Truncate(time.Second)
+		e.ApplySessionDeadline(timestamppb.New(seeded))
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().Equal(seeded))
+
+		e.ApplySessionDeadline(nil)
+
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().Equal(seeded),
+			"nil snapshot must not disturb the existing deadline")
+	})
+
+	t.Run("explicit zero clears a previously-anchored deadline", func(t *testing.T) {
+		e := newEngine()
+		seeded := time.Now().Add(time.Hour).UTC().Truncate(time.Second)
+		e.ApplySessionDeadline(timestamppb.New(seeded))
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().Equal(seeded))
+
+		// Explicit zero Timestamp{} (seconds=0, nanos=0) is the
+		// "expiry disabled / not SSO" sentinel.
+		e.ApplySessionDeadline(&timestamppb.Timestamp{})
+
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().IsZero(),
+			"explicit zero sentinel must clear the deadline")
+	})
+
+	t.Run("invalid timestamp clears the deadline", func(t *testing.T) {
+		e := newEngine()
+		seeded := time.Now().Add(time.Hour).UTC().Truncate(time.Second)
+		e.ApplySessionDeadline(timestamppb.New(seeded))
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().Equal(seeded))
+
+		// Out-of-range nanos → IsValid()==false; same-meaning as the
+		// disabled sentinel for downstream sinks.
+		e.ApplySessionDeadline(&timestamppb.Timestamp{Seconds: 1, Nanos: -1})
+
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().IsZero(),
+			"invalid timestamp must clear the deadline")
+	})
+
+	t.Run("recently expired timestamp stays visible as expired", func(t *testing.T) {
+		e := newEngine()
+		expired := time.Now().Add(-5 * time.Minute).UTC().Truncate(time.Second)
+
+		e.ApplySessionDeadline(timestamppb.New(expired))
+
+		require.True(t, e.statusRecorder.GetSessionExpiresAt().Equal(expired),
+			"recently-expired deadline must stay on the recorder so consumers render it as expired")
+	})
+}

client/internal/engine_sessionwatch.go

@@ -0,0 +1,16 @@
+//go:build !js
+
+package internal
+
+import (
+	"github.com/netbirdio/netbird/client/internal/auth/sessionwatch"
+	"github.com/netbirdio/netbird/client/internal/peer"
+)
+
+// newSessionWatcher returns the real SSO session expiry watcher for every
+// non-wasm build. The js/wasm build gets a no-op stub from
+// engine_sessionwatch_js.go so the sessionwatch package (and its timer
+// machinery) never links into the wasm binary.
+func newSessionWatcher(recorder *peer.Status) sessionDeadlineWatcher {
+	return sessionwatch.New(recorder)
+}

client/internal/engine_sessionwatch_js.go

@@ -0,0 +1,44 @@
+//go:build js
+
+package internal
+
+import (
+	"time"
+
+	"github.com/netbirdio/netbird/client/internal/peer"
+)
+
+// noopSessionWatcher is the js/wasm stand-in for sessionwatch.Watcher. The
+// wasm client never runs the engine's session-warning flow (the interactive
+// T-WarningLead notification and the T-FinalWarningLead fallback dialog live
+// in the desktop UI), so linking the full sessionwatch package (timers, event
+// composition) would only bloat the binary.
+//
+// It still mirrors the deadline into the status recorder so the SubscribeStatus
+// / Status snapshot the UI consumes stays correct — only the timer-driven
+// warnings are dropped.
+type noopSessionWatcher struct {
+	recorder *peer.Status
+}
+
+func newSessionWatcher(recorder *peer.Status) sessionDeadlineWatcher {
+	return noopSessionWatcher{recorder: recorder}
+}
+
+// Update mirrors the real watcher's recorder propagation without the timers or
+// sanity-check sentinels: a valid deadline is exposed on the status snapshot,
+// the zero time clears it.
+func (w noopSessionWatcher) Update(deadline time.Time) error {
+	if w.recorder != nil {
+		w.recorder.SetSessionExpiresAt(deadline)
+	}
+	return nil
+}
+
+func (noopSessionWatcher) Dismiss() {
+	// No-op: only suppresses the timer-driven final-warning, which this stub never arms.
+}
+
+func (noopSessionWatcher) Close() {
+	// No-op: no timers to stop and no state to unwind; the recorder is cleared via Update(zero).
+}

client/internal/engine_test.go

@@ -6,37 +6,18 @@ import (
 	"net"
 	"net/netip"
 	"os"
-	"runtime"
 	"strings"
 	"sync"
 	"testing"
 	"time"
 
-	"github.com/golang/mock/gomock"
-	"github.com/google/uuid"
-	log "github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
-	"go.opentelemetry.io/otel"
 	wgdevice "golang.zx2c4.com/wireguard/device"
 	"golang.zx2c4.com/wireguard/tun/netstack"
 	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
-	"google.golang.org/grpc"
-	"google.golang.org/grpc/keepalive"
 
 	"github.com/netbirdio/netbird/client/internal/stdnet"
-	"github.com/netbirdio/netbird/management/server/job"
-
-	"github.com/netbirdio/netbird/management/server/integrations/integrated_validator/validator"
-
-	"github.com/netbirdio/netbird/management/internals/controllers/network_map/controller"
-	"github.com/netbirdio/netbird/management/internals/controllers/network_map/update_channel"
-	"github.com/netbirdio/netbird/management/internals/modules/peers"
-	"github.com/netbirdio/netbird/management/internals/modules/peers/ephemeral/manager"
-	nbgrpc "github.com/netbirdio/netbird/management/internals/shared/grpc"
-
-	"github.com/netbirdio/netbird/management/internals/server/config"
-	"github.com/netbirdio/netbird/management/server/groups"
 
 	"github.com/netbirdio/netbird/client/iface"
 	"github.com/netbirdio/netbird/client/iface/configurer"
@@ -50,18 +31,7 @@ import (
 	icemaker "github.com/netbirdio/netbird/client/internal/peer/ice"
 	"github.com/netbirdio/netbird/client/internal/profilemanager"
 	"github.com/netbirdio/netbird/client/internal/routemanager"
-	nbssh "github.com/netbirdio/netbird/client/ssh"
-	"github.com/netbirdio/netbird/client/system"
 	nbdns "github.com/netbirdio/netbird/dns"
-	"github.com/netbirdio/netbird/management/server"
-	"github.com/netbirdio/netbird/management/server/activity"
-	nbcache "github.com/netbirdio/netbird/management/server/cache"
-	"github.com/netbirdio/netbird/management/server/integrations/port_forwarding"
-	"github.com/netbirdio/netbird/management/server/permissions"
-	"github.com/netbirdio/netbird/management/server/settings"
-	"github.com/netbirdio/netbird/management/server/store"
-	"github.com/netbirdio/netbird/management/server/telemetry"
-	"github.com/netbirdio/netbird/management/server/types"
 	"github.com/netbirdio/netbird/monotime"
 	"github.com/netbirdio/netbird/route"
 	mgmt "github.com/netbirdio/netbird/shared/management/client"
@@ -69,25 +39,9 @@ import (
 	"github.com/netbirdio/netbird/shared/netiputil"
 	relayClient "github.com/netbirdio/netbird/shared/relay/client"
 	signal "github.com/netbirdio/netbird/shared/signal/client"
-	"github.com/netbirdio/netbird/shared/signal/proto"
-	signalServer "github.com/netbirdio/netbird/signal/server"
 	"github.com/netbirdio/netbird/util"
 )
 
-var (
-	kaep = keepalive.EnforcementPolicy{
-		MinTime:             15 * time.Second,
-		PermitWithoutStream: true,
-	}
-
-	kasp = keepalive.ServerParameters{
-		MaxConnectionIdle:     15 * time.Second,
-		MaxConnectionAgeGrace: 5 * time.Second,
-		Time:                  5 * time.Second,
-		Timeout:               2 * time.Second,
-	}
-)
-
 type MockWGIface struct {
 	CreateFunc                 func() error
 	CreateOnAndroidFunc        func(routeRange []string, ip string, domains []string) error
@@ -224,6 +178,10 @@ func (m *MockWGIface) LastActivities() map[string]monotime.Time {
 	return nil
 }
 
+func (m *MockWGIface) MTU() uint16 {
+	return 1280
+}
+
 func (m *MockWGIface) SetPresharedKey(peerKey string, psk wgtypes.Key, updateOnly bool) error {
 	return nil
 }
@@ -234,129 +192,6 @@ func TestMain(m *testing.M) {
 	os.Exit(code)
 }
 
-func TestEngine_SSH(t *testing.T) {
-	key, err := wgtypes.GeneratePrivateKey()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-
-	sshKey, err := nbssh.GeneratePrivateKey(nbssh.ED25519)
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	relayMgr := relayClient.NewManager(ctx, nil, key.PublicKey().String(), iface.DefaultMTU)
-	engine := NewEngine(
-		ctx, cancel,
-		&EngineConfig{
-			WgIfaceName:      "utun101",
-			WgAddr:           wgaddr.MustParseWGAddress("100.64.0.1/24"),
-			WgPrivateKey:     key,
-			WgPort:           33100,
-			ServerSSHAllowed: true,
-			MTU:              iface.DefaultMTU,
-			SSHKey:           sshKey,
-		},
-		EngineServices{
-			SignalClient:   &signal.MockClient{},
-			MgmClient:      &mgmt.MockClient{},
-			RelayManager:   relayMgr,
-			StatusRecorder: peer.NewRecorder("https://mgm"),
-		},
-		MobileDependency{},
-	)
-
-	engine.dnsServer = &dns.MockServer{
-		UpdateDNSServerFunc: func(serial uint64, update nbdns.Config) error { return nil },
-	}
-
-	err = engine.Start(nil, nil)
-	require.NoError(t, err)
-
-	defer func() {
-		err := engine.Stop()
-		if err != nil {
-			return
-		}
-	}()
-
-	peerWithSSH := &mgmtProto.RemotePeerConfig{
-		WgPubKey:   "MNHf3Ma6z6mdLbriAJbqhX7+nM/B71lgw2+91q3LfhU=",
-		AllowedIps: []string{"100.64.0.21/24"},
-		SshConfig: &mgmtProto.SSHConfig{
-			SshPubKey: []byte("ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIFATYCqaQw/9id1Qkq3n16JYhDhXraI6Pc1fgB8ynEfQ"),
-		},
-	}
-
-	// SSH server is not enabled so SSH config of a remote peer should be ignored
-	networkMap := &mgmtProto.NetworkMap{
-		Serial:             6,
-		PeerConfig:         nil,
-		RemotePeers:        []*mgmtProto.RemotePeerConfig{peerWithSSH},
-		RemotePeersIsEmpty: false,
-	}
-
-	err = engine.updateNetworkMap(networkMap)
-	require.NoError(t, err)
-
-	assert.Nil(t, engine.sshServer)
-
-	// SSH server is enabled, therefore SSH config should be applied
-	networkMap = &mgmtProto.NetworkMap{
-		Serial: 7,
-		PeerConfig: &mgmtProto.PeerConfig{Address: "100.64.0.1/24",
-			SshConfig: &mgmtProto.SSHConfig{
-				SshEnabled: true,
-				JwtConfig: &mgmtProto.JWTConfig{
-					Issuer:       "test-issuer",
-					Audience:     "test-audience",
-					KeysLocation: "test-keys",
-					MaxTokenAge:  3600,
-				},
-			}},
-		RemotePeers:        []*mgmtProto.RemotePeerConfig{peerWithSSH},
-		RemotePeersIsEmpty: false,
-	}
-
-	err = engine.updateNetworkMap(networkMap)
-	require.NoError(t, err)
-
-	time.Sleep(250 * time.Millisecond)
-	assert.NotNil(t, engine.sshServer)
-
-	// now remove peer
-	networkMap = &mgmtProto.NetworkMap{
-		Serial:             8,
-		RemotePeers:        []*mgmtProto.RemotePeerConfig{},
-		RemotePeersIsEmpty: false,
-	}
-
-	err = engine.updateNetworkMap(networkMap)
-	require.NoError(t, err)
-
-	// time.Sleep(250 * time.Millisecond)
-	assert.NotNil(t, engine.sshServer)
-
-	// now disable SSH server
-	networkMap = &mgmtProto.NetworkMap{
-		Serial: 9,
-		PeerConfig: &mgmtProto.PeerConfig{Address: "100.64.0.1/24",
-			SshConfig: &mgmtProto.SSHConfig{SshEnabled: false}},
-		RemotePeers:        []*mgmtProto.RemotePeerConfig{peerWithSSH},
-		RemotePeersIsEmpty: false,
-	}
-
-	err = engine.updateNetworkMap(networkMap)
-	require.NoError(t, err)
-
-	assert.Nil(t, engine.sshServer)
-}
-
 func TestEngine_SSHUpdateLogic(t *testing.T) {
 	// Test that SSH server start/stop logic works based on config
 	engine := &Engine{
@@ -426,7 +261,7 @@ func TestEngine_UpdateNetworkMap(t *testing.T) {
 		return
 	}
 
-	ctx, cancel := context.WithCancel(context.Background())
+	ctx, cancel := context.WithCancel(CtxInitState(context.Background()))
 	defer cancel()
 
 	relayMgr := relayClient.NewManager(ctx, nil, key.PublicKey().String(), iface.DefaultMTU)
@@ -631,97 +466,6 @@ func TestEngine_UpdateNetworkMap(t *testing.T) {
 	}
 }
 
-func TestEngine_Sync(t *testing.T) {
-	key, err := wgtypes.GeneratePrivateKey()
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	// feed updates to Engine via mocked Management client
-	updates := make(chan *mgmtProto.SyncResponse)
-	defer close(updates)
-	syncFunc := func(ctx context.Context, info *system.Info, msgHandler func(msg *mgmtProto.SyncResponse) error) error {
-		for msg := range updates {
-			err := msgHandler(msg)
-			if err != nil {
-				t.Fatal(err)
-			}
-		}
-		return nil
-	}
-	relayMgr := relayClient.NewManager(ctx, nil, key.PublicKey().String(), iface.DefaultMTU)
-	engine := NewEngine(ctx, cancel, &EngineConfig{
-		WgIfaceName:  "utun103",
-		WgAddr:       wgaddr.MustParseWGAddress("100.64.0.1/24"),
-		WgPrivateKey: key,
-		WgPort:       33100,
-		MTU:          iface.DefaultMTU,
-	}, EngineServices{
-		SignalClient:   &signal.MockClient{},
-		MgmClient:      &mgmt.MockClient{SyncFunc: syncFunc},
-		RelayManager:   relayMgr,
-		StatusRecorder: peer.NewRecorder("https://mgm"),
-	}, MobileDependency{})
-	engine.ctx = ctx
-
-	engine.dnsServer = &dns.MockServer{
-		UpdateDNSServerFunc: func(serial uint64, update nbdns.Config) error { return nil },
-	}
-
-	defer func() {
-		err := engine.Stop()
-		if err != nil {
-			return
-		}
-	}()
-
-	err = engine.Start(nil, nil)
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-
-	peer1 := &mgmtProto.RemotePeerConfig{
-		WgPubKey:   "RRHf3Ma6z6mdLbriAJbqhX7+nM/B71lgw2+91q3LfhU=",
-		AllowedIps: []string{"100.64.0.10/24"},
-	}
-	peer2 := &mgmtProto.RemotePeerConfig{
-		WgPubKey:   "LLHf3Ma6z6mdLbriAJbqhX9+nM/B71lgw2+91q3LlhU=",
-		AllowedIps: []string{"100.64.0.11/24"},
-	}
-	peer3 := &mgmtProto.RemotePeerConfig{
-		WgPubKey:   "GGHf3Ma6z6mdLbriAJbqhX9+nM/B71lgw2+91q3LlhU=",
-		AllowedIps: []string{"100.64.0.12/24"},
-	}
-	// 1st update with just 1 peer and serial larger than the current serial of the engine => apply update
-	updates <- &mgmtProto.SyncResponse{
-		NetworkMap: &mgmtProto.NetworkMap{
-			Serial:             10,
-			PeerConfig:         nil,
-			RemotePeers:        []*mgmtProto.RemotePeerConfig{peer1, peer2, peer3},
-			RemotePeersIsEmpty: false,
-		},
-	}
-
-	timeout := time.After(time.Second * 2)
-	for {
-		select {
-		case <-timeout:
-			t.Fatalf("timeout while waiting for test to finish")
-			return
-		default:
-		}
-
-		if getPeers(engine) == 3 && engine.networkSerial == 10 {
-			break
-		}
-	}
-}
-
 func TestEngine_UpdateNetworkMapWithRoutes(t *testing.T) {
 	testCases := []struct {
 		name                 string
@@ -817,7 +561,7 @@ func TestEngine_UpdateNetworkMapWithRoutes(t *testing.T) {
 				return
 			}
 
-			ctx, cancel := context.WithCancel(context.Background())
+			ctx, cancel := context.WithCancel(CtxInitState(context.Background()))
 			defer cancel()
 
 			wgIfaceName := fmt.Sprintf("utun%d", 104+n)
@@ -1024,7 +768,7 @@ func TestEngine_UpdateNetworkMapWithDNSUpdate(t *testing.T) {
 				return
 			}
 
-			ctx, cancel := context.WithCancel(context.Background())
+			ctx, cancel := context.WithCancel(CtxInitState(context.Background()))
 			defer cancel()
 
 			wgIfaceName := fmt.Sprintf("utun%d", 104+n)
@@ -1105,104 +849,6 @@ func TestEngine_UpdateNetworkMapWithDNSUpdate(t *testing.T) {
 	}
 }
 
-func TestEngine_MultiplePeers(t *testing.T) {
-	// log.SetLevel(log.DebugLevel)
-
-	ctx, cancel := context.WithCancel(CtxInitState(context.Background()))
-	defer cancel()
-
-	sigServer, signalAddr, err := startSignal(t)
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer sigServer.Stop()
-	mgmtServer, mgmtAddr, err := startManagement(t, t.TempDir(), "../testdata/store.sql")
-	if err != nil {
-		t.Fatal(err)
-		return
-	}
-	defer mgmtServer.GracefulStop()
-
-	setupKey := "A2C8E62B-38F5-4553-B31E-DD66C696CEBB"
-
-	mu := sync.Mutex{}
-	engines := []*Engine{}
-	numPeers := 10
-	wg := sync.WaitGroup{}
-	wg.Add(numPeers)
-	// create and start peers
-	for i := 0; i < numPeers; i++ {
-		j := i
-		go func() {
-			engine, err := createEngine(ctx, cancel, setupKey, j, mgmtAddr, signalAddr)
-			if err != nil {
-				wg.Done()
-				t.Errorf("unable to create the engine for peer %d with error %v", j, err)
-				return
-			}
-			engine.dnsServer = &dns.MockServer{}
-			mu.Lock()
-			defer mu.Unlock()
-			guid := fmt.Sprintf("{%s}", uuid.New().String())
-			device.CustomWindowsGUIDString = strings.ToLower(guid)
-			err = engine.Start(nil, nil)
-			if err != nil {
-				t.Errorf("unable to start engine for peer %d with error %v", j, err)
-				wg.Done()
-				return
-			}
-			engines = append(engines, engine)
-			wg.Done()
-		}()
-	}
-
-	// wait until all have been created and started
-	wg.Wait()
-	if len(engines) != numPeers {
-		t.Fatal("not all peers was started")
-	}
-	// check whether all the peer have expected peers connected
-
-	expectedConnected := numPeers * (numPeers - 1)
-
-	// adjust according to timeouts
-	timeout := 50 * time.Second
-	timeoutChan := time.After(timeout)
-	ticker := time.NewTicker(time.Second)
-	defer ticker.Stop()
-loop:
-	for {
-		select {
-		case <-timeoutChan:
-			t.Fatalf("waiting for expected connections timeout after %s", timeout.String())
-			break loop
-		case <-ticker.C:
-			totalConnected := 0
-			for _, engine := range engines {
-				totalConnected += getConnectedPeers(engine)
-			}
-			if totalConnected == expectedConnected {
-				log.Infof("total connected=%d", totalConnected)
-				break loop
-			}
-			log.Infof("total connected=%d", totalConnected)
-		}
-	}
-	// cleanup test
-	for n, peerEngine := range engines {
-		t.Logf("stopping peer with interface %s from multipeer test, loopIndex %d", peerEngine.wgInterface.Name(), n)
-		errStop := peerEngine.mgmClient.Close()
-		if errStop != nil {
-			log.Infoln("got error trying to close management clients from engine: ", errStop)
-		}
-		errStop = peerEngine.Stop()
-		if errStop != nil {
-			log.Infoln("got error trying to close testing peers engine: ", errStop)
-		}
-	}
-}
-
 func Test_ParseNATExternalIPMappings(t *testing.T) {
 	ifaceList, err := net.Interfaces()
 	if err != nil {
@@ -1526,187 +1172,6 @@ func TestCompareNetIPLists(t *testing.T) {
 	}
 }
 
-func createEngine(ctx context.Context, cancel context.CancelFunc, setupKey string, i int, mgmtAddr string, signalAddr string) (*Engine, error) {
-	key, err := wgtypes.GeneratePrivateKey()
-	if err != nil {
-		return nil, err
-	}
-	mgmtClient, err := mgmt.NewClient(ctx, mgmtAddr, key, false)
-	if err != nil {
-		return nil, err
-	}
-	signalClient, err := signal.NewClient(ctx, signalAddr, key, false)
-	if err != nil {
-		return nil, err
-	}
-
-	info := system.GetInfo(ctx)
-	resp, err := mgmtClient.Register(setupKey, "", info, nil, nil)
-	if err != nil {
-		return nil, err
-	}
-
-	var ifaceName string
-	if runtime.GOOS == "darwin" {
-		ifaceName = fmt.Sprintf("utun1%d", i)
-	} else {
-		ifaceName = fmt.Sprintf("wt%d", i)
-	}
-
-	wgPort := 33100 + i
-	conf := &EngineConfig{
-		WgIfaceName:  ifaceName,
-		WgAddr:       wgaddr.MustParseWGAddress(resp.PeerConfig.Address),
-		WgPrivateKey: key,
-		WgPort:       wgPort,
-		MTU:          iface.DefaultMTU,
-	}
-
-	relayMgr := relayClient.NewManager(ctx, nil, key.PublicKey().String(), iface.DefaultMTU)
-	e, err := NewEngine(ctx, cancel, conf, EngineServices{
-		SignalClient:   signalClient,
-		MgmClient:      mgmtClient,
-		RelayManager:   relayMgr,
-		StatusRecorder: peer.NewRecorder("https://mgm"),
-	}, MobileDependency{}), nil
-	e.ctx = ctx
-	return e, err
-}
-
-func startSignal(t *testing.T) (*grpc.Server, string, error) {
-	t.Helper()
-
-	s := grpc.NewServer(grpc.KeepaliveEnforcementPolicy(kaep), grpc.KeepaliveParams(kasp))
-
-	lis, err := net.Listen("tcp", "localhost:0")
-	if err != nil {
-		log.Fatalf("failed to listen: %v", err)
-	}
-
-	srv, err := signalServer.NewServer(context.Background(), otel.Meter(""))
-	require.NoError(t, err)
-	proto.RegisterSignalExchangeServer(s, srv)
-
-	go func() {
-		if err = s.Serve(lis); err != nil {
-			log.Fatalf("failed to serve: %v", err)
-		}
-	}()
-
-	return s, lis.Addr().String(), nil
-}
-
-func startManagement(t *testing.T, dataDir, testFile string) (*grpc.Server, string, error) {
-	t.Helper()
-
-	config := &config.Config{
-		Stuns:      []*config.Host{},
-		TURNConfig: &config.TURNConfig{},
-		Relay: &config.Relay{
-			Addresses:      []string{"127.0.0.1:1234"},
-			CredentialsTTL: util.Duration{Duration: time.Hour},
-			Secret:         "222222222222222222",
-		},
-		Signal: &config.Host{
-			Proto: "http",
-			URI:   "localhost:10000",
-		},
-		Datadir:    dataDir,
-		HttpConfig: nil,
-	}
-
-	lis, err := net.Listen("tcp", "localhost:0")
-	if err != nil {
-		return nil, "", err
-	}
-	s := grpc.NewServer(grpc.KeepaliveEnforcementPolicy(kaep), grpc.KeepaliveParams(kasp))
-
-	store, cleanUp, err := store.NewTestStoreFromSQL(context.Background(), testFile, config.Datadir)
-	if err != nil {
-		return nil, "", err
-	}
-	t.Cleanup(cleanUp)
-
-	eventStore := &activity.InMemoryEventStore{}
-	if err != nil {
-		return nil, "", err
-	}
-
-	permissionsManager := permissions.NewManager(store)
-	peersManager := peers.NewManager(store, permissionsManager)
-	jobManager := job.NewJobManager(nil, store, peersManager)
-
-	cacheStore, err := nbcache.NewStore(context.Background(), 100*time.Millisecond, 300*time.Millisecond, 100)
-	if err != nil {
-		return nil, "", err
-	}
-
-	ia, _ := validator.NewIntegratedValidator(context.Background(), peersManager, nil, eventStore, cacheStore)
-
-	metrics, err := telemetry.NewDefaultAppMetrics(context.Background())
-	require.NoError(t, err)
-
-	ctrl := gomock.NewController(t)
-	t.Cleanup(ctrl.Finish)
-	settingsMockManager := settings.NewMockManager(ctrl)
-	settingsMockManager.EXPECT().
-		GetSettings(gomock.Any(), gomock.Any(), gomock.Any()).
-		Return(&types.Settings{}, nil).
-		AnyTimes()
-	settingsMockManager.EXPECT().
-		GetExtraSettings(gomock.Any(), gomock.Any()).
-		Return(&types.ExtraSettings{}, nil).
-		AnyTimes()
-
-	groupsManager := groups.NewManagerMock()
-
-	updateManager := update_channel.NewPeersUpdateManager(metrics)
-	requestBuffer := server.NewAccountRequestBuffer(context.Background(), store)
-	networkMapController := controller.NewController(context.Background(), store, metrics, updateManager, requestBuffer, server.MockIntegratedValidator{}, settingsMockManager, "netbird.selfhosted", port_forwarding.NewControllerMock(), manager.NewEphemeralManager(store, peersManager), config)
-	accountManager, err := server.BuildManager(context.Background(), config, store, networkMapController, jobManager, nil, "", eventStore, nil, false, ia, metrics, port_forwarding.NewControllerMock(), settingsMockManager, permissionsManager, false, cacheStore)
-	if err != nil {
-		return nil, "", err
-	}
-
-	secretsManager, err := nbgrpc.NewTimeBasedAuthSecretsManager(updateManager, config.TURNConfig, config.Relay, settingsMockManager, groupsManager)
-	if err != nil {
-		return nil, "", err
-	}
-	mgmtServer, err := nbgrpc.NewServer(config, accountManager, settingsMockManager, jobManager, secretsManager, nil, nil, &server.MockIntegratedValidator{}, networkMapController, nil, nil)
-	if err != nil {
-		return nil, "", err
-	}
-	mgmtProto.RegisterManagementServiceServer(s, mgmtServer)
-	go func() {
-		if err = s.Serve(lis); err != nil {
-			log.Fatalf("failed to serve: %v", err)
-		}
-	}()
-
-	return s, lis.Addr().String(), nil
-}
-
-// getConnectedPeers returns a connection Status or nil if peer connection wasn't found
-func getConnectedPeers(e *Engine) int {
-	e.syncMsgMux.Lock()
-	defer e.syncMsgMux.Unlock()
-	i := 0
-	for _, id := range e.peerStore.PeersPubKey() {
-		conn, _ := e.peerStore.PeerConn(id)
-		if conn.IsConnected() {
-			i++
-		}
-	}
-	return i
-}
-
-func getPeers(e *Engine) int {
-	e.syncMsgMux.Lock()
-	defer e.syncMsgMux.Unlock()
-
-	return len(e.peerStore.PeersPubKey())
-}
-
 func mustEncodePrefix(t *testing.T, p netip.Prefix) []byte {
 	t.Helper()
 	b, err := netiputil.EncodePrefix(p)

client/internal/engine_tunsettings.go

@@ -0,0 +1,20 @@
+package internal
+
+func (e *Engine) TunSettings() ([]string, []string) {
+	e.syncMsgMux.Lock()
+	routeManager := e.routeManager
+	dnsServer := e.dnsServer
+	e.syncMsgMux.Unlock()
+
+	var routes []string
+	if routeManager != nil {
+		routes = routeManager.CurrentRouteRange()
+	}
+
+	var searchDomains []string
+	if dnsServer != nil {
+		searchDomains = dnsServer.SearchDomains()
+	}
+
+	return routes, searchDomains
+}

client/internal/iface_common.go

@@ -44,4 +44,5 @@ type wgIfaceBase interface {
 	FullStats() (*configurer.Stats, error)
 	LastActivities() map[string]monotime.Time
 	SetPresharedKey(peerKey string, psk wgtypes.Key, updateOnly bool) error
+	MTU() uint16
 }

client/internal/ipcauth/creds_stub.go

@@ -0,0 +1,31 @@
+//go:build !linux && !darwin && !freebsd && !windows
+
+package ipcauth
+
+import (
+	"errors"
+	"net"
+
+	"google.golang.org/grpc/credentials"
+)
+
+// errUnsupported is returned on platforms with no local peer-identity
+// primitive, so consumers fail closed instead of guessing an identity.
+var errUnsupported = errors.New("peer identity is not available on this platform")
+
+// NewTransportCredentials returns nil: without a peer-identity primitive the
+// daemon cannot authenticate local callers, and the caller must treat that as
+// "authorization cannot be enforced".
+func NewTransportCredentials() credentials.TransportCredentials {
+	return nil
+}
+
+// PeerIdentity always fails on this platform.
+func PeerIdentity(net.Conn) (Identity, error) {
+	return Identity{}, errUnsupported
+}
+
+// ConnIdentity always fails on this platform.
+func ConnIdentity(net.Conn) (Identity, error) {
+	return Identity{}, errUnsupported
+}

client/internal/ipcauth/creds_unix.go

@@ -0,0 +1,56 @@
+//go:build linux || darwin || freebsd
+
+package ipcauth
+
+import (
+	"context"
+	"net"
+
+	"google.golang.org/grpc/credentials"
+)
+
+// NewTransportCredentials returns gRPC transport credentials that expose the
+// caller's kernel-authenticated identity via IdentityFromContext. It returns
+// nil on platforms that have no peer-identity primitive, which the caller must
+// treat as "authorization cannot be enforced".
+//
+// The handshake exchanges no bytes on the wire, so a client dialing with
+// insecure credentials interoperates with a server using these. That keeps
+// older CLI and UI binaries working against an upgraded daemon.
+func NewTransportCredentials() credentials.TransportCredentials {
+	return unixCreds{}
+}
+
+// ConnIdentity extracts the caller's identity from an accepted local IPC
+// connection. It is shared by the gRPC transport credentials and by the JSON
+// gateway, which reads the identity of its own HTTP clients.
+func ConnIdentity(conn net.Conn) (Identity, error) {
+	return PeerIdentity(conn)
+}
+
+type unixCreds struct{}
+
+func (unixCreds) ClientHandshake(_ context.Context, _ string, conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	return conn, AuthInfo{}, nil
+}
+
+// ServerHandshake extracts the peer identity and fails closed when it cannot
+// be read, so a connection whose caller is unknown never reaches a handler.
+func (unixCreds) ServerHandshake(conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	id, err := ConnIdentity(conn)
+	if err != nil {
+		return nil, nil, err
+	}
+	return conn, AuthInfo{
+		CommonAuthInfo: credentials.CommonAuthInfo{SecurityLevel: credentials.NoSecurity},
+		Identity:       id,
+	}, nil
+}
+
+func (unixCreds) Info() credentials.ProtocolInfo {
+	return credentials.ProtocolInfo{SecurityProtocol: AuthInfo{}.AuthType()}
+}
+
+func (unixCreds) Clone() credentials.TransportCredentials { return unixCreds{} }
+
+func (unixCreds) OverrideServerName(string) error { return nil }

client/internal/ipcauth/creds_windows.go

@@ -0,0 +1,194 @@
+//go:build windows
+
+package ipcauth
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"runtime"
+
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/windows"
+	"google.golang.org/grpc/credentials"
+)
+
+var (
+	modadvapi32                    = windows.NewLazySystemDLL("advapi32.dll")
+	procImpersonateNamedPipeClient = modadvapi32.NewProc("ImpersonateNamedPipeClient")
+)
+
+// DefaultPipeSDDL is the security descriptor for the daemon control pipe.
+//
+//	D:P          protected DACL, no inheritance
+//	(A;;GA;;;SY) allow GENERIC_ALL to LocalSystem (the daemon's service account)
+//	(A;;GA;;;WD) allow GENERIC_ALL to Everyone
+//
+// Any local caller may connect, as with a Unix socket at 0666; what a caller may
+// actually do is decided from its token, not from the DACL. Remote callers are not
+// a concern here: winio.ListenPipe creates the pipe with
+// FILE_PIPE_REJECT_REMOTE_CLIENTS, so NPFS rejects connections from other machines
+// before the descriptor is consulted.
+//
+// A deny ACE on the NETWORK SID would not add anything and would break callers:
+// that SID is present in any network-logon token, which includes OpenSSH and WinRM
+// sessions, so it denies administrators driving the CLI over SSH and denies the
+// daemon itself when started from such a session.
+func DefaultPipeSDDL() string {
+	return "D:P(A;;GA;;;SY)(A;;GA;;;WD)"
+}
+
+// NewTransportCredentials returns gRPC transport credentials that derive the
+// caller's identity from the named-pipe client token.
+//
+// The client must connect at SECURITY_IDENTIFICATION for the daemon to be able
+// to read its token, which is what DialNamedPipe does.
+func NewTransportCredentials() credentials.TransportCredentials {
+	return winpipeCreds{}
+}
+
+// ConnIdentity extracts the caller's identity from an accepted named-pipe
+// connection by impersonating the pipe client and reading its token. It is
+// shared by the gRPC transport credentials and by the JSON gateway, which
+// reads the identity of its own HTTP clients.
+func ConnIdentity(conn net.Conn) (Identity, error) {
+	// go-winio's pipe connection embeds *win32File, which exposes Fd().
+	fdConn, ok := conn.(interface{ Fd() uintptr })
+	if !ok {
+		return Identity{}, fmt.Errorf("connection %T does not expose a pipe handle", conn)
+	}
+	return pipeClientIdentity(windows.Handle(fdConn.Fd()))
+}
+
+type winpipeCreds struct{}
+
+func (winpipeCreds) ClientHandshake(_ context.Context, _ string, conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	return conn, AuthInfo{}, nil
+}
+
+// ServerHandshake extracts the connecting client's identity and fails closed
+// when the handle or token cannot be read, so a connection whose caller is
+// unknown never reaches a handler.
+func (winpipeCreds) ServerHandshake(conn net.Conn) (net.Conn, credentials.AuthInfo, error) {
+	id, err := ConnIdentity(conn)
+	if err != nil {
+		return nil, nil, err
+	}
+	return conn, AuthInfo{
+		CommonAuthInfo: credentials.CommonAuthInfo{SecurityLevel: credentials.NoSecurity},
+		Identity:       id,
+	}, nil
+}
+
+func (winpipeCreds) Info() credentials.ProtocolInfo {
+	return credentials.ProtocolInfo{SecurityProtocol: AuthInfo{}.AuthType()}
+}
+
+func (winpipeCreds) Clone() credentials.TransportCredentials { return winpipeCreds{} }
+
+func (winpipeCreds) OverrideServerName(string) error { return nil }
+
+// pipeClientIdentity reads the connecting client's user SID, usable group
+// SIDs, and elevation state by impersonating the pipe client on this thread
+// and reading the resulting impersonation token.
+func pipeClientIdentity(handle windows.Handle) (id Identity, err error) {
+	// Impersonation is per-thread, so the goroutine must stay on this thread
+	// until RevertToSelf, otherwise an unrelated goroutine could inherit the
+	// impersonated context.
+	runtime.LockOSThread()
+
+	// The thread only goes back to the runtime's pool once it is provably no
+	// longer impersonating the client. If the revert fails, leaving it locked
+	// makes Go terminate it when this goroutine exits, which costs one thread
+	// and keeps a thread running as the client from ever being reused.
+	clean := false
+	defer func() {
+		if clean {
+			runtime.UnlockOSThread()
+		}
+	}()
+
+	if err = impersonateNamedPipeClient(handle); err != nil {
+		clean = true
+		return Identity{}, fmt.Errorf("impersonate named pipe client: %w", err)
+	}
+	defer func() {
+		// Surface the revert failure only when nothing else failed: leaving
+		// the thread impersonated is worse than the original error.
+		revErr := windows.RevertToSelf()
+		if revErr != nil {
+			if err == nil {
+				err = fmt.Errorf("revert impersonation: %w", revErr)
+			}
+			return
+		}
+		clean = true
+	}()
+
+	// openAsSelf=true opens the token with the daemon's own process context
+	// rather than the impersonated client's, so the open cannot fail because
+	// the client lacks access to its own token.
+	var token windows.Token
+	if err = windows.OpenThreadToken(windows.CurrentThread(), windows.TOKEN_QUERY, true, &token); err != nil {
+		return Identity{}, fmt.Errorf("open thread token: %w", err)
+	}
+	defer func() {
+		if cerr := token.Close(); cerr != nil {
+			log.Debugf("close client token: %v", cerr)
+		}
+	}()
+
+	return identityFromToken(token)
+}
+
+// identityFromToken reads the user SID, usable group SIDs and elevation state
+// out of a Windows token.
+func identityFromToken(token windows.Token) (Identity, error) {
+	user, err := token.GetTokenUser()
+	if err != nil {
+		return Identity{}, fmt.Errorf("read token user: %w", err)
+	}
+
+	groups, err := tokenGroupSIDs(token)
+	if err != nil {
+		return Identity{}, err
+	}
+
+	return Identity{
+		SID:      user.User.Sid.String(),
+		Groups:   groups,
+		Elevated: token.IsElevated(),
+	}, nil
+}
+
+// tokenGroupSIDs returns the SIDs of the groups the token can actually
+// exercise. Groups that are disabled or marked deny-only are skipped: a
+// UAC-filtered administrator carries BUILTIN\Administrators as deny-only, and
+// treating that as membership would hand every admin account privilege it
+// cannot currently use.
+func tokenGroupSIDs(token windows.Token) ([]string, error) {
+	tg, err := token.GetTokenGroups()
+	if err != nil {
+		return nil, fmt.Errorf("read token groups: %w", err)
+	}
+
+	var sids []string
+	for _, g := range tg.AllGroups() {
+		if g.Attributes&windows.SE_GROUP_ENABLED == 0 {
+			continue
+		}
+		if g.Attributes&windows.SE_GROUP_USE_FOR_DENY_ONLY != 0 {
+			continue
+		}
+		sids = append(sids, g.Sid.String())
+	}
+	return sids, nil
+}
+
+func impersonateNamedPipeClient(h windows.Handle) error {
+	r, _, e := procImpersonateNamedPipeClient.Call(uintptr(h))
+	if r == 0 {
+		return e
+	}
+	return nil
+}

client/internal/ipcauth/forward.go

@@ -0,0 +1,272 @@
+package ipcauth
+
+import (
+	"context"
+	"crypto/rand"
+	"crypto/subtle"
+	"encoding/hex"
+	"fmt"
+	"slices"
+	"strconv"
+	"strings"
+
+	"google.golang.org/grpc/metadata"
+)
+
+// Metadata keys the local JSON gateway uses to forward the identity of its own
+// HTTP client to the daemon. The gateway runs inside the daemon process and
+// re-dials the daemon over the control socket, so without forwarding every
+// JSON request would appear to come from the daemon itself.
+const (
+	// mdFwd marks a request as forwarded by the JSON gateway. It is always
+	// set, even when the gateway could not read its client's identity, so the
+	// daemon can tell "no identity available" apart from "not forwarded".
+	mdFwd         = "x-netbird-fwd"
+	mdFwdUID      = "x-netbird-fwd-uid"      // Unix user ID
+	mdFwdGID      = "x-netbird-fwd-gid"      // Unix primary group ID
+	mdFwdSID      = "x-netbird-fwd-sid"      // Windows user SID
+	mdFwdGroup    = "x-netbird-fwd-group"    // Windows group SID, repeated
+	mdFwdElevated = "x-netbird-fwd-elevated" // Windows, "1" when elevated
+
+	// mdFwdProof proves the forwarded identity was stamped by this process. The
+	// gateway runs inside the daemon, so a secret held in memory is available to
+	// the only legitimate producer and to nothing else.
+	mdFwdProof = "x-netbird-fwd-proof"
+)
+
+// forwardKeys is every metadata key the gateway sets. An HTTP client must never
+// be able to supply one itself: see IsReservedForwardKey.
+var forwardKeys = []string{mdFwd, mdFwdUID, mdFwdGID, mdFwdSID, mdFwdGroup, mdFwdElevated, mdFwdProof}
+
+// forwardProof authenticates the gateway's forwarding metadata. It is generated
+// once per daemon process and never leaves it: it is not written to disk, not
+// logged, and not sent anywhere except over the daemon's own control socket to
+// itself.
+//
+// Without it, trusting a forwarded identity rests on every layer in front of it
+// stripping incoming forwarding keys, and on each key's value shape being
+// distinguishable from an injected one. A single injected group SID or an
+// injected "elevated" flag has the same shape as a legitimate one, so no
+// cardinality rule can catch it. Requiring the proof means metadata that did not
+// come from this process is refused whatever it contains.
+var forwardProof = mustForwardProof()
+
+func mustForwardProof() string {
+	var buf [32]byte
+	if _, err := rand.Read(buf[:]); err != nil {
+		// Continuing would leave the forwarded path authenticated by a
+		// predictable value, which is worse than not starting.
+		panic(fmt.Sprintf("generate identity forwarding proof: %v", err))
+	}
+	return hex.EncodeToString(buf[:])
+}
+
+// IsReservedForwardKey reports whether a gRPC metadata key belongs to the
+// gateway's identity forwarding, and therefore must be dropped when it arrives
+// from outside.
+//
+// grpc-gateway maps "Grpc-Metadata-<key>" request headers into gRPC metadata and
+// joins them ahead of the values its own annotators add. Without dropping these,
+// an HTTP client could hand the daemon "x-netbird-fwd-uid: 0" and be believed,
+// because the daemon trusts forwarded metadata when the transport peer is the
+// (privileged) gateway.
+func IsReservedForwardKey(key string) bool {
+	key = strings.ToLower(key)
+	return slices.Contains(forwardKeys, key)
+}
+
+// ForwardIdentityMetadata encodes an HTTP client's identity for the JSON
+// gateway to forward to the daemon. When known is false only the marker is
+// set, which makes the daemon treat the caller as unidentified rather than as
+// the daemon itself.
+func ForwardIdentityMetadata(id Identity, known bool) metadata.MD {
+	md := metadata.MD{}
+	md.Set(mdFwd, "1")
+	md.Set(mdFwdProof, forwardProof)
+	if !known {
+		return md
+	}
+
+	if id.IsWindows() {
+		md.Set(mdFwdSID, id.SID)
+		if len(id.Groups) > 0 {
+			md.Set(mdFwdGroup, id.Groups...)
+		}
+		if id.Elevated {
+			md.Set(mdFwdElevated, "1")
+		}
+		return md
+	}
+
+	md.Set(mdFwdUID, strconv.FormatUint(uint64(id.UID), 10))
+	md.Set(mdFwdGID, strconv.FormatUint(uint64(id.GID), 10))
+	return md
+}
+
+// CallerIdentity returns the identity to authorize a request against. For a
+// direct connection that is the transport peer's kernel identity. For a
+// request relayed by the local JSON gateway it is the identity the gateway
+// forwarded, since the transport peer is then the daemon itself.
+//
+// A forwarded identity is only honoured when the transport peer is the daemon's
+// own identity and the metadata carries this process's forwarding proof, so
+// forged forwarding metadata gains a caller nothing. A forwarded request that
+// carries no identity is reported as unidentified, never as the daemon.
+//
+// The second return value is false when no identity could be established, and
+// callers MUST fail closed in that case.
+func CallerIdentity(ctx context.Context) (Identity, bool) {
+	id, ok := IdentityFromContext(ctx)
+	if !ok {
+		return Identity{}, false
+	}
+
+	// A forwarding key that arrives more than once did not come from the gateway
+	// alone, so nothing about the request can be trusted to describe its caller.
+	// Refusing outright matters because the alternative reading, "not forwarded",
+	// would authorize the request as the transport peer, which on the gateway's
+	// connection is the daemon itself.
+	if duplicatedForwardKey(ctx) {
+		return Identity{}, false
+	}
+
+	forwarded := isForwarded(ctx)
+
+	// Our own process on the other end of the socket is the JSON gateway, the only
+	// thing that dials the daemon from inside it. Such a call must carry a
+	// forwarded identity; without one there is no caller to authorize, and
+	// treating it as the daemon would authorize whatever reached the JSON socket.
+	// Only Linux reports the peer PID, so this is a belt on top of the gateway's
+	// interceptor rather than the sole guarantee.
+	if id.PID != 0 && int(id.PID) == selfPID && !forwarded {
+		return Identity{}, false
+	}
+
+	// Only the gateway's own connection may speak for someone else. Being
+	// privileged is not enough and not the point: the gateway runs inside the
+	// daemon, so it dials as the daemon's identity whatever user that is, which
+	// also covers a rootless container.
+	if !forwarded || !IsDaemonSelf(id) {
+		return id, true
+	}
+
+	// Speaking for someone else additionally requires the proof only this process
+	// holds. Refusing is the only safe reading: the transport peer here is the
+	// daemon itself, so falling back to it would authorize the request as the
+	// daemon. This is also what makes the forwarded values trustworthy once
+	// accepted, so they need no shape checks of their own.
+	if !authenticForward(ctx) {
+		return Identity{}, false
+	}
+
+	return forwardedIdentity(ctx)
+}
+
+// duplicatedForwardKey reports whether any forwarding key carries more than one
+// value. The gateway's interceptor sets each key exactly once and replaces what
+// was already there, so a repeat means a second source supplied it.
+func duplicatedForwardKey(ctx context.Context) bool {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		return false
+	}
+	for _, key := range forwardKeys {
+		// Group SIDs are legitimately repeated; the rest identify the caller.
+		if key == mdFwdGroup {
+			continue
+		}
+		if len(md.Get(key)) > 1 {
+			return true
+		}
+	}
+	return false
+}
+
+// authenticForward reports whether the request carries this process's forwarding
+// proof, which only the in-process JSON gateway can supply.
+func authenticForward(ctx context.Context) bool {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		return false
+	}
+	got := mdSingle(md, mdFwdProof)
+	return subtle.ConstantTimeCompare([]byte(got), []byte(forwardProof)) == 1
+}
+
+// isForwarded reports whether the request carries the JSON gateway marker.
+func isForwarded(ctx context.Context) bool {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		return false
+	}
+	return mdSingle(md, mdFwd) != ""
+}
+
+// forwardedIdentity decodes the identity the JSON gateway attached.
+func forwardedIdentity(ctx context.Context) (Identity, bool) {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		return Identity{}, false
+	}
+
+	if sid := mdSingle(md, mdFwdSID); sid != "" {
+		return Identity{
+			SID: sid,
+			// Repeated by design, one value per group, and only reachable once
+			// the forwarding proof has been verified.
+			Groups:   md.Get(mdFwdGroup),
+			Elevated: mdSingle(md, mdFwdElevated) == "1",
+		}, true
+	}
+
+	uid, err := strconv.ParseUint(mdSingle(md, mdFwdUID), 10, 32)
+	if err != nil {
+		return Identity{}, false
+	}
+
+	id := Identity{UID: uint32(uid)}
+	if gid, err := strconv.ParseUint(mdSingle(md, mdFwdGID), 10, 32); err == nil {
+		id.GID = uint32(gid)
+	}
+	return id, true
+}
+
+// mdSingle returns the value of a forwarded key only when exactly one was
+// supplied. The gateway's interceptor sets each key exactly once, so more than one
+// value means something else also supplied it, and the whole identity is treated as
+// unknown rather than picking a winner. Defence in depth behind the gateway's
+// header filter.
+func mdSingle(md metadata.MD, key string) string {
+	if v := md.Get(key); len(v) == 1 {
+		return v[0]
+	}
+	return ""
+}
+
+// WithForwardedIdentity stamps id onto a context's outgoing metadata for the JSON
+// gateway's call to the daemon, replacing any forwarding keys already present so
+// values supplied from outside cannot survive alongside it.
+//
+// This is deliberately not done with runtime.WithMetadata: grpc-gateway skips its
+// annotators entirely when no request header maps to metadata ("if len(pairs) == 0
+// { return ctx, nil, nil }", runtime/context.go), which an HTTP/1.0 request with no
+// Host header over a unix socket achieves. The daemon would then see an unmarked
+// call whose transport peer is the daemon's own identity, and authorize it as the
+// daemon. A client interceptor runs for every RPC regardless of headers.
+func WithForwardedIdentity(ctx context.Context, id Identity, known bool) context.Context {
+	md, ok := metadata.FromOutgoingContext(ctx)
+	if !ok {
+		md = metadata.MD{}
+	} else {
+		md = md.Copy()
+	}
+
+	for _, key := range forwardKeys {
+		delete(md, key)
+	}
+	for key, values := range ForwardIdentityMetadata(id, known) {
+		md[key] = values
+	}
+
+	return metadata.NewOutgoingContext(ctx, md)
+}

client/internal/ipcauth/forward_test.go

@@ -0,0 +1,214 @@
+package ipcauth
+
+import (
+	"context"
+	"testing"
+
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/peer"
+)
+
+// transportCtx builds a request context as the daemon's transport credentials
+// would: the identity of whoever opened the socket, plus whatever metadata the
+// request carried.
+func transportCtx(id Identity, md metadata.MD) context.Context {
+	ctx := peer.NewContext(context.Background(), &peer.Peer{
+		AuthInfo: AuthInfo{
+			CommonAuthInfo: credentials.CommonAuthInfo{SecurityLevel: credentials.NoSecurity},
+			Identity:       id,
+		},
+	})
+	if md != nil {
+		ctx = metadata.NewIncomingContext(ctx, md)
+	}
+	return ctx
+}
+
+var (
+	root       = Identity{UID: 0}
+	unprivUser = Identity{UID: 1000, GID: 1000}
+)
+
+// asDaemon pins which identity counts as this process for the duration of a test.
+// Without it the test binary's own uid decides, which silently changes what
+// "the gateway" means.
+func asDaemon(t *testing.T, id Identity) {
+	t.Helper()
+	prevID, prevKnown, prevDelegate := selfIdentity, selfKnown, selfMayDelegate
+	t.Cleanup(func() { selfIdentity, selfKnown, selfMayDelegate = prevID, prevKnown, prevDelegate })
+	selfIdentity, selfKnown = id, true
+	selfMayDelegate = !id.IsPrivileged()
+}
+
+func TestCallerIdentity_DirectConnections(t *testing.T) {
+	t.Run("no transport credentials is not an identity", func(t *testing.T) {
+		if _, ok := CallerIdentity(context.Background()); ok {
+			t.Fatal("a caller with no credentials must not be identified")
+		}
+	})
+
+	t.Run("a direct caller is its transport identity", func(t *testing.T) {
+		id, ok := CallerIdentity(transportCtx(unprivUser, nil))
+		if !ok || id.UID != 1000 {
+			t.Fatalf("got %v ok=%t, want uid 1000", id, ok)
+		}
+	})
+
+	// The whole point of honouring forwarded metadata only from a privileged
+	// transport peer: an unprivileged caller can set any metadata it likes on its
+	// own connection to the daemon socket.
+	t.Run("an unprivileged caller cannot forge an identity", func(t *testing.T) {
+		asDaemon(t, root)
+		forged := metadata.Pairs(mdFwd, "1", mdFwdUID, "0", mdFwdGID, "0")
+		id, ok := CallerIdentity(transportCtx(unprivUser, forged))
+		if !ok {
+			t.Fatal("caller should still be identified, as itself")
+		}
+		if id.IsPrivileged() || id.UID != 1000 {
+			t.Fatalf("forged metadata was believed: got %v", id)
+		}
+	})
+}
+
+func TestCallerIdentity_GatewayForwarding(t *testing.T) {
+	t.Run("the gateway's client identity is used, not the gateway's own", func(t *testing.T) {
+		asDaemon(t, root)
+		md := ForwardIdentityMetadata(unprivUser, true)
+		id, ok := CallerIdentity(transportCtx(root, md))
+		if !ok {
+			t.Fatal("forwarded identity should be usable")
+		}
+		if id.IsPrivileged() || id.UID != 1000 {
+			t.Fatalf("got %v, want the forwarded uid 1000 and not privileged", id)
+		}
+	})
+
+	t.Run("a privileged gateway client stays privileged", func(t *testing.T) {
+		asDaemon(t, root)
+		md := ForwardIdentityMetadata(root, true)
+		id, ok := CallerIdentity(transportCtx(root, md))
+		if !ok || !id.IsPrivileged() {
+			t.Fatalf("got %v ok=%t, want a privileged identity", id, ok)
+		}
+	})
+
+	// A JSON socket the gateway cannot read peer credentials from (a TCP socket,
+	// say) must not make every request look like the daemon itself.
+	t.Run("an unreadable client identity is unknown, not the daemon", func(t *testing.T) {
+		asDaemon(t, root)
+		md := ForwardIdentityMetadata(Identity{}, false)
+		if _, ok := CallerIdentity(transportCtx(root, md)); ok {
+			t.Fatal("a forwarded request with no identity must not be identified")
+		}
+	})
+
+	// grpc-gateway turns Grpc-Metadata-<key> headers into gRPC metadata and joins
+	// them ahead of its annotators' values. If an HTTP client's header survived
+	// that, this is the shape the daemon would see: the attacker's uid 0 first,
+	// the real uid second. The gateway filters those headers out, and reading a
+	// duplicated key as unknown makes the daemon safe even if it did not.
+	t.Run("a duplicated key from an injected header is not believed", func(t *testing.T) {
+		asDaemon(t, root)
+		md := metadata.MD{}
+		md.Append(mdFwd, "1")
+		md.Append(mdFwdUID, "0")    // injected by the HTTP client
+		md.Append(mdFwdUID, "1000") // appended by the gateway's annotator
+		if id, ok := CallerIdentity(transportCtx(root, md)); ok {
+			t.Fatalf("injected uid was accepted: got %v", id)
+		}
+	})
+
+	t.Run("a duplicated marker is not believed either", func(t *testing.T) {
+		asDaemon(t, root)
+		md := metadata.MD{}
+		md.Append(mdFwd, "1")
+		md.Append(mdFwd, "1")
+		md.Append(mdFwdUID, "1000")
+		// A repeated marker must not be read as "not forwarded": that would
+		// authorize the request as the transport peer, which on the gateway's
+		// connection is the daemon itself.
+		if id, ok := CallerIdentity(transportCtx(root, md)); ok {
+			t.Fatalf("a duplicated marker was believed: got %v", id)
+		}
+	})
+
+	// The layers in front of this (the gateway's header matcher, and its
+	// interceptor replacing every forwarding key) are what keep outside metadata
+	// from arriving at all. The proof is what the daemon can check for itself, and
+	// it is the only defence that works for a value whose legitimate shape is
+	// indistinguishable from an injected one: a lone group SID, or "elevated".
+	t.Run("forwarding metadata without this process's proof is refused", func(t *testing.T) {
+		asDaemon(t, root)
+		for name, md := range map[string]metadata.MD{
+			"no proof":    metadata.Pairs(mdFwd, "1", mdFwdUID, "0"),
+			"wrong proof": metadata.Pairs(mdFwd, "1", mdFwdUID, "0", mdFwdProof, "deadbeef"),
+			"windows identity without a proof": metadata.Pairs(mdFwd, "1",
+				mdFwdSID, "S-1-5-21-1-2-3-1001", mdFwdGroup, sidAdministrators, mdFwdElevated, "1"),
+		} {
+			t.Run(name, func(t *testing.T) {
+				if id, ok := CallerIdentity(transportCtx(root, md)); ok {
+					t.Fatalf("unstamped forwarding metadata was believed: got %v", id)
+				}
+			})
+		}
+	})
+
+	// A caller that reaches the gateway cannot see the proof, so it cannot append
+	// a group of its own to a genuine forwarded identity: doing so would have to
+	// go through the interceptor, which replaces the whole set.
+	t.Run("a group appended to a stamped identity does not survive the interceptor", func(t *testing.T) {
+		asDaemon(t, root)
+		injected := metadata.MD{}
+		injected.Append(mdFwdGroup, sidAdministrators)
+
+		ctx := WithForwardedIdentity(metadata.NewOutgoingContext(context.Background(), injected),
+			Identity{SID: "S-1-5-21-1-2-3-1001"}, true)
+		out, ok := metadata.FromOutgoingContext(ctx)
+		if !ok {
+			t.Fatal("no outgoing metadata")
+		}
+		if groups := out.Get(mdFwdGroup); len(groups) != 0 {
+			t.Fatalf("injected group survived: %v", groups)
+		}
+	})
+}
+
+func TestIsReservedForwardKey(t *testing.T) {
+	for _, key := range forwardKeys {
+		if !IsReservedForwardKey(key) {
+			t.Errorf("%q must be reserved", key)
+		}
+	}
+
+	// grpc-gateway canonicalises header names, so the check has to be
+	// case-insensitive.
+	if !IsReservedForwardKey("X-Netbird-Fwd-Uid") {
+		t.Error("the check must be case-insensitive")
+	}
+
+	for _, key := range []string{"authorization", "x-netbird", "x-netbird-fwd-uid-extra", ""} {
+		if IsReservedForwardKey(key) {
+			t.Errorf("%q must not be reserved", key)
+		}
+	}
+}
+
+func TestForwardIdentityMetadata_AlwaysMarksForwarded(t *testing.T) {
+	for _, tc := range []struct {
+		name  string
+		id    Identity
+		known bool
+	}{
+		{"known unix identity", unprivUser, true},
+		{"unknown identity", Identity{}, false},
+		{"windows identity", Identity{SID: "S-1-5-21-1-2-3-1001", Elevated: true}, true},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			md := ForwardIdentityMetadata(tc.id, tc.known)
+			if got := md.Get(mdFwd); len(got) != 1 || got[0] != "1" {
+				t.Fatalf("marker = %v, want exactly one \"1\"", got)
+			}
+		})
+	}
+}

client/internal/ipcauth/identity.go

@@ -0,0 +1,127 @@
+// Package ipcauth provides the kernel-authenticated identity of a local IPC
+// (gRPC) caller and the transport credentials that surface it into the gRPC
+// context, so the daemon can authorize individual RPCs by caller identity.
+//
+// On Unix the identity is read from the kernel via SO_PEERCRED (Linux) or
+// LOCAL_PEERCRED (Darwin/FreeBSD). On Windows it is derived from the
+// named-pipe client token. Platforms without a peer-identity primitive get no
+// credentials, and every consumer must fail closed when no identity is
+// available.
+package ipcauth
+
+import (
+	"context"
+	"fmt"
+	"slices"
+
+	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/peer"
+)
+
+// Well-known Windows SIDs that identify a fully privileged principal.
+const (
+	sidLocalSystem    = "S-1-5-18"     // NT AUTHORITY\SYSTEM
+	sidLocalService   = "S-1-5-19"     // NT AUTHORITY\LOCAL SERVICE
+	sidNetworkService = "S-1-5-20"     // NT AUTHORITY\NETWORK SERVICE
+	sidAdministrators = "S-1-5-32-544" // BUILTIN\Administrators
+)
+
+// Identity is the kernel-authenticated identity of a local IPC caller. The
+// zero value is not a valid identity: consumers must only use one obtained
+// with a true ok/nil error return.
+type Identity struct {
+	// UID and GID are the caller's Unix user ID and primary group ID. Both are
+	// zero on Windows, where SID is authoritative instead.
+	UID uint32
+	GID uint32
+
+	// SID is the caller's Windows security identifier, empty on Unix.
+	SID string
+
+	// Groups holds the caller's Windows group SIDs, captured from the client
+	// token at handshake time. Only groups that are enabled and not
+	// deny-only are captured, so a group listed here is one the caller can
+	// actually exercise. Empty on Unix.
+	Groups []string
+
+	// Elevated reports whether the Windows client token is elevated (running
+	// as administrator, or an administrator with UAC turned off). Always false
+	// on Unix, where privilege is uid 0.
+	Elevated bool
+
+	// PID is the caller's process ID where the platform reports it (Linux's
+	// SO_PEERCRED), and 0 where it does not. It identifies the daemon's own
+	// process dialling itself, which is what the JSON gateway does, and is never
+	// used to grant anything.
+	PID int32
+}
+
+// IsWindows reports whether this identity is a Windows principal (SID-based)
+// rather than a Unix uid/gid principal.
+func (i Identity) IsWindows() bool {
+	return i.SID != ""
+}
+
+// IsPrivileged reports whether the caller is the platform's administrative
+// principal, which is what the daemon requires for changes that cross the
+// user-to-root boundary.
+//
+// On Windows the decision comes from the caller's token rather than from
+// account names or group RIDs: an elevated token, one of the service accounts
+// the daemon itself may run as, or a token with BUILTIN\Administrators
+// enabled. A UAC-filtered administrator has that group marked deny-only, and
+// deny-only groups are dropped when the identity is captured, so such a
+// caller is correctly reported as unprivileged. Domain group memberships
+// (Domain Admins and friends) are deliberately not consulted: they say
+// nothing about what this token may do on this machine.
+func (i Identity) IsPrivileged() bool {
+	if !i.IsWindows() {
+		return i.UID == 0
+	}
+
+	if i.Elevated {
+		return true
+	}
+
+	switch i.SID {
+	case sidLocalSystem, sidLocalService, sidNetworkService:
+		return true
+	}
+
+	return slices.Contains(i.Groups, sidAdministrators)
+}
+
+// String renders the identity for audit logs and denial messages.
+func (i Identity) String() string {
+	if i.IsWindows() {
+		return fmt.Sprintf("sid=%s elevated=%t", i.SID, i.Elevated)
+	}
+	return fmt.Sprintf("uid=%d gid=%d", i.UID, i.GID)
+}
+
+// AuthInfo carries the peer Identity as a gRPC credentials.AuthInfo so
+// handlers can retrieve it from the request context via IdentityFromContext.
+type AuthInfo struct {
+	credentials.CommonAuthInfo
+	Identity Identity
+}
+
+// AuthType identifies the authentication scheme.
+func (AuthInfo) AuthType() string { return "netbird-ipc-peercred" }
+
+// IdentityFromContext extracts the caller's kernel-authenticated identity from
+// the gRPC peer context. The second return value is false when no IPC
+// transport credentials were negotiated, which happens on a TCP daemon socket
+// and on platforms without a peer-identity primitive. Callers MUST fail closed
+// in that case.
+func IdentityFromContext(ctx context.Context) (Identity, bool) {
+	p, ok := peer.FromContext(ctx)
+	if !ok {
+		return Identity{}, false
+	}
+	info, ok := p.AuthInfo.(AuthInfo)
+	if !ok {
+		return Identity{}, false
+	}
+	return info.Identity, true
+}

client/internal/ipcauth/ownedfile.go

@@ -0,0 +1,63 @@
+package ipcauth
+
+import (
+	"fmt"
+	"os"
+)
+
+// OpenOwnedFile opens path for reading on behalf of the IPC caller identified by
+// id, and fails unless the opened file is a regular file that id owns.
+//
+// It exists for the paths a local caller hands to the daemon over the IPC. The
+// daemon runs as root, so opening such a path unchecked lets any local user read
+// any file through it. Ownership is the invariant that keeps the daemon from
+// reading, with its own privileges, a file the caller could not read itself: a
+// symlink or hard link planted at the path resolves to a file someone else owns
+// and is refused.
+//
+// The check is made against the open descriptor rather than the path, so
+// swapping the path between the check and the read cannot change the answer.
+//
+// A privileged caller is exempt: it can read the file directly, so refusing it
+// here would protect nothing. The regular-file requirement still applies to
+// everyone, since a fifo or device planted at the path is never a log file.
+func OpenOwnedFile(id Identity, path string) (*os.File, error) {
+	f, err := openForRead(path)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := checkOwnership(id, f); err != nil {
+		if cerr := f.Close(); cerr != nil {
+			return nil, fmt.Errorf("%w (close: %v)", err, cerr)
+		}
+		return nil, err
+	}
+
+	return f, nil
+}
+
+func checkOwnership(id Identity, f *os.File) error {
+	info, err := f.Stat()
+	if err != nil {
+		return fmt.Errorf("stat %s: %w", f.Name(), err)
+	}
+
+	if !info.Mode().IsRegular() {
+		return fmt.Errorf("%s is not a regular file", f.Name())
+	}
+
+	if IsPrivilegedCaller(id) {
+		return nil
+	}
+
+	owned, err := fileOwnedBy(id, f)
+	if err != nil {
+		return fmt.Errorf("read owner of %s: %w", f.Name(), err)
+	}
+	if !owned {
+		return fmt.Errorf("%s is not owned by the caller (%s)", f.Name(), id)
+	}
+
+	return nil
+}

client/internal/ipcauth/ownedfile_test.go

@@ -0,0 +1,64 @@
+package ipcauth
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+// otherIdentity is an unprivileged caller that owns nothing the test creates.
+func otherIdentity(t *testing.T) Identity {
+	t.Helper()
+	if runtime.GOOS == "windows" {
+		return Identity{SID: "S-1-5-21-1-2-3-1001"}
+	}
+	return Identity{UID: uint32(os.Geteuid() + 1), GID: uint32(os.Getegid() + 1)}
+}
+
+func TestOpenOwnedFileReadsFileOwnedByCaller(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "gui-client.log")
+	require.NoError(t, os.WriteFile(path, []byte("hello"), 0600))
+
+	id, err := CurrentProcessIdentity()
+	require.NoError(t, err)
+
+	f, err := OpenOwnedFile(id, path)
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = f.Close() })
+
+	content, err := io.ReadAll(f)
+	require.NoError(t, err)
+	require.Equal(t, "hello", string(content))
+}
+
+func TestOpenOwnedFileRefusesFileOwnedByAnother(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "gui-client.log")
+	require.NoError(t, os.WriteFile(path, []byte("secret"), 0600))
+
+	_, err := OpenOwnedFile(otherIdentity(t), path)
+	require.ErrorContains(t, err, "not owned by the caller")
+}
+
+func TestOpenOwnedFileRefusesNonRegularFile(t *testing.T) {
+	dir := t.TempDir()
+
+	// The caller owns the directory, so this is the regular-file requirement
+	// talking, not the ownership check.
+	id, err := CurrentProcessIdentity()
+	require.NoError(t, err)
+
+	_, err = OpenOwnedFile(id, dir)
+	require.ErrorContains(t, err, "not a regular file")
+}
+
+func TestOpenOwnedFileRefusesMissingFile(t *testing.T) {
+	id, err := CurrentProcessIdentity()
+	require.NoError(t, err)
+
+	_, err = OpenOwnedFile(id, filepath.Join(t.TempDir(), "absent.log"))
+	require.Error(t, err)
+}

client/internal/ipcauth/ownedfile_unix.go

@@ -0,0 +1,35 @@
+//go:build !windows
+
+package ipcauth
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+)
+
+// openForRead opens a caller-supplied path without following a symlink at its
+// final component and without blocking: a fifo planted at the path would
+// otherwise stall the open until a writer appears, and the daemon holds a lock
+// while it collects the file.
+func openForRead(path string) (*os.File, error) {
+	f, err := os.OpenFile(path, os.O_RDONLY|syscall.O_NOFOLLOW|syscall.O_NONBLOCK, 0)
+	if err != nil {
+		return nil, fmt.Errorf("open %s: %w", path, err)
+	}
+	return f, nil
+}
+
+func fileOwnedBy(id Identity, f *os.File) (bool, error) {
+	info, err := f.Stat()
+	if err != nil {
+		return false, err
+	}
+
+	stat, ok := info.Sys().(*syscall.Stat_t)
+	if !ok {
+		return false, fmt.Errorf("no owner information in %T", info.Sys())
+	}
+
+	return stat.Uid == id.UID, nil
+}

client/internal/ipcauth/ownedfile_unix_test.go

@@ -0,0 +1,57 @@
+//go:build !windows
+
+package ipcauth
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+	"syscall"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+)
+
+// A symlink is the shape the arbitrary-read attempt takes: the caller owns the
+// link, the file it points at belongs to someone else.
+func TestOpenOwnedFileRefusesSymlink(t *testing.T) {
+	dir := t.TempDir()
+	target := filepath.Join(dir, "target.log")
+	require.NoError(t, os.WriteFile(target, []byte("secret"), 0600))
+
+	link := filepath.Join(dir, "gui-client.log")
+	require.NoError(t, os.Symlink(target, link))
+
+	id, err := CurrentProcessIdentity()
+	require.NoError(t, err)
+
+	_, err = OpenOwnedFile(id, link)
+	// O_NOFOLLOW on a symlink reports ELOOP on Linux/Darwin and EMLINK on FreeBSD.
+	if !errors.Is(err, syscall.ELOOP) && !errors.Is(err, syscall.EMLINK) {
+		t.Fatalf("symlink open: got %v, want ELOOP or EMLINK", err)
+	}
+}
+
+// A fifo would block the open until a writer showed up, stalling the daemon
+// while it holds its lock.
+func TestOpenOwnedFileRefusesFifoWithoutBlocking(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "gui-client.log")
+	require.NoError(t, syscall.Mkfifo(path, 0600))
+
+	id, err := CurrentProcessIdentity()
+	require.NoError(t, err)
+
+	done := make(chan error, 1)
+	go func() {
+		_, err := OpenOwnedFile(id, path)
+		done <- err
+	}()
+
+	select {
+	case err := <-done:
+		require.ErrorContains(t, err, "not a regular file")
+	case <-time.After(5 * time.Second):
+		t.Fatal("opening a fifo blocked")
+	}
+}

client/internal/ipcauth/ownedfile_windows.go

@@ -0,0 +1,59 @@
+//go:build windows
+
+package ipcauth
+
+import (
+	"fmt"
+	"os"
+
+	"golang.org/x/sys/windows"
+)
+
+// openForRead opens a caller-supplied path without following a reparse point at
+// it. FILE_FLAG_OPEN_REPARSE_POINT is the Windows analogue of O_NOFOLLOW: it
+// opens a symlink/junction itself rather than its target, so the regular-file
+// check in checkOwnership refuses a link the caller planted to redirect the
+// read. FILE_FLAG_BACKUP_SEMANTICS lets a directory open too (as os.Open does),
+// so a directory planted at the path is refused as non-regular rather than
+// erroring here. The share mode matches os.Open so a log being written stays
+// openable.
+func openForRead(path string) (*os.File, error) {
+	p, err := windows.UTF16PtrFromString(path)
+	if err != nil {
+		return nil, fmt.Errorf("convert path %s: %w", path, err)
+	}
+
+	handle, err := windows.CreateFile(
+		p,
+		windows.GENERIC_READ,
+		windows.FILE_SHARE_READ|windows.FILE_SHARE_WRITE|windows.FILE_SHARE_DELETE,
+		nil,
+		windows.OPEN_EXISTING,
+		windows.FILE_FLAG_OPEN_REPARSE_POINT|windows.FILE_FLAG_BACKUP_SEMANTICS,
+		0,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("open %s: %w", path, err)
+	}
+
+	return os.NewFile(uintptr(handle), path), nil
+}
+
+// fileOwnedBy compares the file's owner SID with the caller's. Files an elevated
+// process creates are owned by BUILTIN\Administrators rather than by the user,
+// but such a caller is privileged and never reaches this check.
+func fileOwnedBy(id Identity, f *os.File) (bool, error) {
+	// x/sys/windows GetSecurityInfo frees the OS buffer itself and returns a
+	// Go-heap copy, so there is nothing to LocalFree here.
+	sd, err := windows.GetSecurityInfo(windows.Handle(f.Fd()), windows.SE_FILE_OBJECT, windows.OWNER_SECURITY_INFORMATION)
+	if err != nil {
+		return false, fmt.Errorf("read security info: %w", err)
+	}
+
+	owner, _, err := sd.Owner()
+	if err != nil {
+		return false, fmt.Errorf("read owner: %w", err)
+	}
+
+	return id.SID != "" && owner.String() == id.SID, nil
+}

client/internal/ipcauth/ownedfile_windows_test.go

@@ -0,0 +1,78 @@
+//go:build windows
+
+package ipcauth
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"golang.org/x/sys/windows"
+)
+
+// fileOwnerSID reads the owner SID of path the same way OpenOwnedFile does, so
+// the test can construct an Identity that matches (or deliberately does not).
+func fileOwnerSID(t *testing.T, path string) string {
+	t.Helper()
+	f, err := os.Open(path)
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = f.Close() })
+
+	sd, err := windows.GetSecurityInfo(windows.Handle(f.Fd()), windows.SE_FILE_OBJECT, windows.OWNER_SECURITY_INFORMATION)
+	require.NoError(t, err)
+	owner, _, err := sd.Owner()
+	require.NoError(t, err)
+	return owner.String()
+}
+
+// The allow branch of fileOwnedBy is the SID-equality path the legitimate GUI
+// flow depends on. Running elevated, a created file is owned by
+// BUILTIN\Administrators; an Identity carrying that SID with Elevated=false and
+// no groups is unprivileged by IsPrivileged (which reads the token, not the
+// SID's RID), so this exercises the real GetSecurityInfo equality rather than
+// the privileged-caller shortcut.
+func TestOpenOwnedFileWindowsOwnerMatchAllows(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "gui-client.log")
+	require.NoError(t, os.WriteFile(path, []byte("hello"), 0600))
+
+	ownerSID := fileOwnerSID(t, path)
+	id := Identity{SID: ownerSID}
+	require.False(t, id.IsPrivileged(), "identity built from the owner SID must be unprivileged for this to test the match path")
+
+	f, err := OpenOwnedFile(id, path)
+	require.NoError(t, err)
+	_ = f.Close()
+}
+
+func TestOpenOwnedFileWindowsOwnerMismatchRefuses(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "gui-client.log")
+	require.NoError(t, os.WriteFile(path, []byte("secret"), 0600))
+
+	other := Identity{SID: "S-1-5-21-9-9-9-9999"}
+	require.False(t, other.IsPrivileged())
+
+	_, err := OpenOwnedFile(other, path)
+	require.ErrorContains(t, err, "not owned by the caller")
+}
+
+// FILE_FLAG_OPEN_REPARSE_POINT must make OpenOwnedFile refuse a symlink the same
+// way O_NOFOLLOW does on Unix, so a planted link can't redirect the read to
+// another file. Creating a symlink needs a privilege the runner may lack, so the
+// test skips rather than fails when it can't.
+func TestOpenOwnedFileWindowsRefusesSymlink(t *testing.T) {
+	dir := t.TempDir()
+	target := filepath.Join(dir, "target.log")
+	require.NoError(t, os.WriteFile(target, []byte("secret"), 0600))
+
+	link := filepath.Join(dir, "gui-client.log")
+	if err := os.Symlink(target, link); err != nil {
+		t.Skipf("cannot create symlink (privilege not held?): %v", err)
+	}
+
+	id, err := CurrentProcessIdentity()
+	require.NoError(t, err)
+
+	_, err = OpenOwnedFile(id, link)
+	require.Error(t, err, "a symlink must be refused")
+}

client/internal/ipcauth/peercred_bsd.go

@@ -0,0 +1,43 @@
+//go:build darwin || freebsd
+
+package ipcauth
+
+import (
+	"fmt"
+	"net"
+
+	"golang.org/x/sys/unix"
+)
+
+// PeerIdentity reads the kernel-authenticated identity of the process on the
+// other end of a Unix socket via LOCAL_PEERCRED. The xucred is recorded by the
+// kernel at connect() time and carries the peer's uid and its group list, of
+// which the first entry is the primary group.
+func PeerIdentity(conn net.Conn) (Identity, error) {
+	uc, ok := conn.(*net.UnixConn)
+	if !ok {
+		return Identity{}, fmt.Errorf("connection is not a unix socket: %T", conn)
+	}
+
+	raw, err := uc.SyscallConn()
+	if err != nil {
+		return Identity{}, fmt.Errorf("raw conn: %w", err)
+	}
+
+	var cred *unix.Xucred
+	var credErr error
+	if err := raw.Control(func(fd uintptr) {
+		cred, credErr = unix.GetsockoptXucred(int(fd), unix.SOL_LOCAL, unix.LOCAL_PEERCRED)
+	}); err != nil {
+		return Identity{}, fmt.Errorf("control raw conn: %w", err)
+	}
+	if credErr != nil {
+		return Identity{}, fmt.Errorf("read LOCAL_PEERCRED: %w", credErr)
+	}
+
+	id := Identity{UID: cred.Uid}
+	if cred.Ngroups > 0 {
+		id.GID = cred.Groups[0]
+	}
+	return id, nil
+}

client/internal/ipcauth/peercred_linux.go

@@ -0,0 +1,39 @@
+//go:build linux
+
+package ipcauth
+
+import (
+	"fmt"
+	"net"
+
+	"golang.org/x/sys/unix"
+)
+
+// PeerIdentity reads the kernel-authenticated identity of the process on the
+// other end of a Unix socket via SO_PEERCRED. The credentials are recorded by
+// the kernel at connect() time and cannot be changed for the life of the
+// connection, so they are not spoofable by the caller.
+func PeerIdentity(conn net.Conn) (Identity, error) {
+	uc, ok := conn.(*net.UnixConn)
+	if !ok {
+		return Identity{}, fmt.Errorf("connection is not a unix socket: %T", conn)
+	}
+
+	raw, err := uc.SyscallConn()
+	if err != nil {
+		return Identity{}, fmt.Errorf("raw conn: %w", err)
+	}
+
+	var cred *unix.Ucred
+	var credErr error
+	if err := raw.Control(func(fd uintptr) {
+		cred, credErr = unix.GetsockoptUcred(int(fd), unix.SOL_SOCKET, unix.SO_PEERCRED)
+	}); err != nil {
+		return Identity{}, fmt.Errorf("control raw conn: %w", err)
+	}
+	if credErr != nil {
+		return Identity{}, fmt.Errorf("read SO_PEERCRED: %w", credErr)
+	}
+
+	return Identity{UID: cred.Uid, GID: cred.Gid, PID: cred.Pid}, nil
+}

client/internal/ipcauth/pipeserver_windows.go

@@ -0,0 +1,87 @@
+//go:build windows
+
+package ipcauth
+
+import (
+	"fmt"
+	"net"
+
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/sys/windows"
+)
+
+// PipeServerTrusted reports an error unless the pipe behind conn was created by a
+// principal this client may hand secrets to. Clients call it for a pipe whose name
+// carries no guarantee of its own, which is any name outside the
+// ProtectedPrefix\Administrators namespace: that namespace already restricts
+// creation to administrators and LocalSystem, while a plain name can be created by
+// any local user before the daemon gets there.
+//
+// The decision is made from the pipe object's owner, not from the serving process,
+// because a client cannot open a process running as another user at all, and the
+// legitimate case is precisely an unprivileged client talking to a privileged
+// daemon. Trusted owners are the service accounts, BUILTIN\Administrators, and
+// this client's own user, the last of which is the daemon a user runs themselves
+// as in netstack mode. A pipe owned by anyone else gets no setup key, pre-shared
+// key or SSO prompt out of this client.
+func PipeServerTrusted(conn net.Conn) error {
+	// go-winio's pipe connection embeds *win32File, which exposes Fd().
+	fdConn, ok := conn.(interface{ Fd() uintptr })
+	if !ok {
+		return fmt.Errorf("connection %T does not expose a pipe handle", conn)
+	}
+
+	owner, err := pipeOwnerSID(windows.Handle(fdConn.Fd()))
+	if err != nil {
+		return err
+	}
+
+	if !trustedPipeOwner(owner) {
+		return fmt.Errorf("pipe owned by %s, which is neither an administrator nor this user", owner)
+	}
+	return nil
+}
+
+// PipeOwnedBySelf reports whether the pipe behind conn was created by this very
+// user, which is how a client recognises a daemon running as itself. Ownership it
+// cannot read is reported as false.
+func PipeOwnedBySelf(conn net.Conn) bool {
+	fdConn, ok := conn.(interface{ Fd() uintptr })
+	if !ok {
+		return false
+	}
+
+	owner, err := pipeOwnerSID(windows.Handle(fdConn.Fd()))
+	if err != nil {
+		log.Debugf("read daemon pipe owner: %v", err)
+		return false
+	}
+	return selfKnown && selfIdentity.SID != "" && owner == selfIdentity.SID
+}
+
+// pipeOwnerSID reads the owner of the pipe object a client is connected to. The
+// handle was opened with GENERIC_READ, which includes READ_CONTROL, so no extra
+// access is needed.
+func pipeOwnerSID(handle windows.Handle) (string, error) {
+	sd, err := windows.GetSecurityInfo(handle, windows.SE_KERNEL_OBJECT, windows.OWNER_SECURITY_INFORMATION)
+	if err != nil {
+		return "", fmt.Errorf("read pipe security info: %w", err)
+	}
+
+	owner, _, err := sd.Owner()
+	if err != nil {
+		return "", fmt.Errorf("read pipe owner: %w", err)
+	}
+	return owner.String(), nil
+}
+
+// trustedPipeOwner reports whether a pipe's owner is a principal a client may
+// speak to. An elevated process's objects are owned by BUILTIN\Administrators by
+// default, an unelevated one's by the user, which is why both forms appear here.
+func trustedPipeOwner(owner string) bool {
+	switch owner {
+	case sidLocalSystem, sidLocalService, sidNetworkService, sidAdministrators:
+		return true
+	}
+	return selfKnown && selfIdentity.SID != "" && owner == selfIdentity.SID
+}