ignore siblings when add/remove peer from group

Signed-off-by: Dmitri Dolguikh <dmitri.external@netbird.io>

README.md

@@ -33,7 +33,7 @@
   <br/>
   <br/>
   <strong>
-    🚀 <a href="https://netbird.io/careers">We are hiring! Join us at https://netbird.io/careers</a>
+    🚀 <a href="https://careers.netbird.io">We are hiring! Join us at careers.netbird.io</a>
   </strong>
 </p>
 

client/internal/dns/mgmt/mgmt.go

@@ -51,20 +51,13 @@ type cachedRecord struct {
 }
 
 // Resolver caches critical NetBird infrastructure domains.
-// records, refreshing, failedResolves, mgmtDomain and serverDomains are all
-// guarded by mutex.
+// records, refreshing, 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
@@ -83,10 +76,9 @@ 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),
-		failedResolves: make(map[domain.Domain]time.Time),
-		cacheTTL:       resolveCacheTTL(),
+		records:    make(map[dns.Question]*cachedRecord),
+		refreshing: make(map[dns.Question]*atomic.Bool),
+		cacheTTL:   resolveCacheTTL(),
 	}
 }
 
@@ -181,9 +173,7 @@ 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. 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.
+// entry for that qtype.
 func (m *Resolver) AddDomain(ctx context.Context, d domain.Domain) error {
 	dnsName := strings.ToLower(dns.Fqdn(d.PunycodeString()))
 
@@ -213,10 +203,6 @@ 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
 }
 
@@ -476,7 +462,6 @@ 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
@@ -520,7 +505,6 @@ 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)
@@ -593,85 +577,13 @@ func (m *Resolver) isManagementDomain(domain domain.Domain) bool {
 	return m.mgmtDomain != nil && domain == *m.mgmtDomain
 }
 
-// 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.
+// addNewDomains resolves and caches all domains from the 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 _, 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)
+		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())
 		}
 	}
 }

client/internal/dns/mgmt/mgmt_refresh_test.go

@@ -21,7 +21,6 @@ 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()
@@ -31,7 +30,6 @@ func newFakeChain() *fakeChain {
 	return &fakeChain{
 		calls:   map[string]int{},
 		answers: map[string][]dns.RR{},
-		qErr:    map[string]error{},
 		hasRoot: true,
 	}
 }
@@ -49,9 +47,6 @@ 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()
 
@@ -80,12 +75,6 @@ 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

@@ -1,183 +0,0 @@
-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")
-}

management/server/affected_peers_coverage_test.go

@@ -41,7 +41,7 @@ func TestAffectedPeers_DependencyCoverageMatrix(t *testing.T) {
 				_, err := s.manager.SavePolicy(ctx, s.accountID, userID, peerToResourcePolicyByGroup(s.sourceGroupID, s.resourceGroupID), true)
 				require.NoError(t, err)
 				return affectedpeers.Change{ChangedPeerIDs: []string{s.routerPeerID}},
-					[]string{s.sourcePeerID}, []string{s.unrelatedPeerID}
+					[]string{s.sourcePeerID, s.routerPeerID}, []string{s.unrelatedPeerID}
 			},
 		},
 		{
@@ -106,12 +106,8 @@ func TestAffectedPeers_DependencyCoverageMatrix(t *testing.T) {
 			change, mustContain, mustExclude := r.build(t, s, ctx)
 			affected := resolveAffected(t, s.manager.Store, s.accountID, change)
 
-			for _, id := range mustContain {
-				assert.Contains(t, affected, id, "expected peer to be affected")
-			}
-			for _, id := range mustExclude {
-				assert.NotContains(t, affected, id, "peer must not be affected")
-			}
+			assert.ElementsMatch(t, affected, mustContain, "expected peer to be affected")
+			assert.NotContains(t, affected, mustExclude, "peer must not be affected")
 		})
 	}
 }

management/server/affected_peers_test.go

@@ -96,33 +96,54 @@ func affectedGroupID(i int) string   { return fmt.Sprintf("affected-grp-%d", i)
 func affectedGroupName(i int) string { return fmt.Sprintf("AffectedGroup%d", i) }
 
 func TestCollectGroupChange_PolicyLinked(t *testing.T) {
-	manager, s, accountID, _, groupIDs := setupAffectedPeersTest(t)
+	manager, s, accountID, peerIDs, groupIDs := setupAffectedPeersTest(t)
 	ctx := context.Background()
 
 	_, err := manager.SavePolicy(ctx, accountID, userID, &types.Policy{
 		Enabled: true,
 		Rules: []*types.PolicyRule{
 			{
-				Enabled:       true,
-				Sources:       []string{groupIDs[0]},
-				Destinations:  []string{groupIDs[1]},
-				Bidirectional: true,
-				Action:        types.PolicyTrafficActionAccept,
+				Enabled:             true,
+				Sources:             []string{groupIDs[0]},
+				Destinations:        []string{groupIDs[1]},
+				SourceResource:      types.Resource{ID: peerIDs[0], Type: types.ResourceTypePeer},
+				DestinationResource: types.Resource{ID: peerIDs[1], Type: types.ResourceTypePeer},
+				Bidirectional:       true,
+				Action:              types.PolicyTrafficActionAccept,
+			},
+			{
+				Enabled:             true,
+				Sources:             []string{groupIDs[0]},
+				Destinations:        []string{groupIDs[1]},
+				SourceResource:      types.Resource{ID: peerIDs[2], Type: types.ResourceTypeHost},
+				DestinationResource: types.Resource{ID: peerIDs[3], Type: types.ResourceTypeHost},
+				Bidirectional:       true,
+				Action:              types.PolicyTrafficActionAccept,
+			},
+			{
+				Enabled:             true,
+				Sources:             []string{groupIDs[0]},
+				Destinations:        []string{groupIDs[1]},
+				SourceResource:      types.Resource{ID: "", Type: types.ResourceTypePeer},
+				DestinationResource: types.Resource{ID: "", Type: types.ResourceTypePeer},
+				Bidirectional:       true,
+				Action:              types.PolicyTrafficActionAccept,
 			},
 		},
 	}, true)
 	require.NoError(t, err)
 
-	groups, _ := collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[0]})
-	assert.Contains(t, groups, groupIDs[0])
-	assert.Contains(t, groups, groupIDs[1])
+	groups, directPeers := collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[0]})
+	assert.ElementsMatch(t, groups, []string{groupIDs[0], groupIDs[1]})
+	assert.ElementsMatch(t, directPeers, []string{peerIDs[1]})
 
-	groups, _ = collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[1]})
-	assert.Contains(t, groups, groupIDs[0])
-	assert.Contains(t, groups, groupIDs[1])
+	groups, directPeers = collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[1]})
+	assert.ElementsMatch(t, groups, []string{groupIDs[0], groupIDs[1]})
+	assert.ElementsMatch(t, directPeers, []string{peerIDs[0]})
 
-	groups, _ = collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[2]})
+	groups, directPeers = collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[2]})
 	assert.Empty(t, groups)
+	assert.Empty(t, directPeers)
 }
 
 func TestCollectGroupChange_PolicyWithDirectPeerResource(t *testing.T) {
@@ -133,20 +154,44 @@ func TestCollectGroupChange_PolicyWithDirectPeerResource(t *testing.T) {
 		Enabled: true,
 		Rules: []*types.PolicyRule{
 			{
-				Enabled:        true,
-				Sources:        []string{groupIDs[0]},
-				SourceResource: types.Resource{ID: peerIDs[3], Type: types.ResourceTypePeer},
-				Destinations:   []string{groupIDs[1]},
-				Action:         types.PolicyTrafficActionAccept,
+				Enabled:             true,
+				Sources:             []string{groupIDs[0]},
+				SourceResource:      types.Resource{ID: peerIDs[3], Type: types.ResourceTypePeer},
+				DestinationResource: types.Resource{ID: peerIDs[4], Type: types.ResourceTypePeer},
+				Destinations:        []string{groupIDs[1]},
+				Action:              types.PolicyTrafficActionAccept,
+			},
+			{
+				Enabled:             true,
+				Sources:             []string{groupIDs[0]},
+				SourceResource:      types.Resource{ID: peerIDs[1], Type: types.ResourceTypeHost},
+				DestinationResource: types.Resource{ID: peerIDs[2], Type: types.ResourceTypeHost},
+				Destinations:        []string{groupIDs[1]},
+				Action:              types.PolicyTrafficActionAccept,
+			},
+			{
+				Enabled:             true,
+				Sources:             []string{groupIDs[0]},
+				SourceResource:      types.Resource{ID: "", Type: types.ResourceTypePeer},
+				DestinationResource: types.Resource{ID: "", Type: types.ResourceTypePeer},
+				Destinations:        []string{groupIDs[1]},
+				Action:              types.PolicyTrafficActionAccept,
 			},
 		},
 	}, true)
 	require.NoError(t, err)
 
 	groups, directPeers := collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[0]})
-	assert.Contains(t, groups, groupIDs[0])
-	assert.Contains(t, groups, groupIDs[1])
-	assert.Contains(t, directPeers, peerIDs[3])
+	assert.ElementsMatch(t, groups, []string{groupIDs[0], groupIDs[1]})
+	assert.ElementsMatch(t, directPeers, []string{peerIDs[4]})
+
+	groups, directPeers = collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[1]})
+	assert.ElementsMatch(t, groups, []string{groupIDs[0], groupIDs[1]})
+	assert.ElementsMatch(t, directPeers, []string{peerIDs[3]})
+
+	groups, directPeers = collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[2]})
+	assert.Empty(t, groups)
+	assert.Empty(t, directPeers)
 }
 
 func TestCollectGroupChange_PolicyWithNonPeerResource_NoDirectPeers(t *testing.T) {
@@ -168,8 +213,7 @@ func TestCollectGroupChange_PolicyWithNonPeerResource_NoDirectPeers(t *testing.T
 	require.NoError(t, err)
 
 	groups, directPeers := collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[0]})
-	assert.Contains(t, groups, groupIDs[0])
-	assert.Contains(t, groups, groupIDs[1])
+	assert.ElementsMatch(t, groups, []string{groupIDs[0], groupIDs[1]})
 	assert.Empty(t, directPeers, "non-peer resources should not produce direct peer IDs")
 }
 
@@ -373,17 +417,11 @@ func TestCollectGroupChange_MultipleEntities(t *testing.T) {
 	require.NoError(t, err)
 
 	groups, directPeers := collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[0]})
-	assert.Contains(t, groups, groupIDs[0])
-	assert.Contains(t, groups, groupIDs[1])
-	assert.NotContains(t, groups, groupIDs[2])
-	assert.NotContains(t, groups, groupIDs[3])
+	assert.ElementsMatch(t, groups, []string{groupIDs[0], groupIDs[1]})
 	assert.Empty(t, directPeers)
 
 	groups, directPeers = collectGroupChangeAffectedGroups(ctx, s, accountID, []string{groupIDs[3]})
-	assert.Contains(t, groups, groupIDs[2])
-	assert.Contains(t, groups, groupIDs[3])
-	assert.NotContains(t, groups, groupIDs[0])
-	assert.NotContains(t, groups, groupIDs[1])
+	assert.ElementsMatch(t, groups, []string{groupIDs[2], groupIDs[3]})
 	assert.Empty(t, directPeers)
 }
 
@@ -452,8 +490,9 @@ func TestResolveAffectedPeers_PolicyBetweenTwoGroups(t *testing.T) {
 	result = manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[1]})
 	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[1]}, result)
 
+	// peerIDs[2] is unrelated to the route; only its own map can change.
 	result = manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[2]})
-	assert.Empty(t, result)
+	assert.ElementsMatch(t, []string{peerIDs[2]}, result)
 }
 
 func TestResolveAffectedPeers_PolicyThreeGroups(t *testing.T) {
@@ -474,7 +513,7 @@ func TestResolveAffectedPeers_PolicyThreeGroups(t *testing.T) {
 	require.NoError(t, err)
 
 	result := manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[0]})
-	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[1], peerIDs[2]}, result)
+	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[2]}, result)
 }
 
 func TestResolveAffectedPeers_RoutePeerGroups(t *testing.T) {
@@ -506,8 +545,9 @@ func TestResolveAffectedPeers_RoutePeerGroups(t *testing.T) {
 	result = manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[1]})
 	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[1]}, result)
 
+	// peerIDs[2] is in no policy; only its own map can change, so it refreshes itself.
 	result = manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[2]})
-	assert.Empty(t, result)
+	assert.ElementsMatch(t, []string{peerIDs[2]}, result)
 }
 
 func TestResolveAffectedPeers_RouteWithDirectPeer(t *testing.T) {
@@ -564,9 +604,9 @@ func TestResolveAffectedPeers_RouteWithAccessControlGroups(t *testing.T) {
 	result := manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[2]})
 	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[1], peerIDs[2]}, result)
 
-	// peer3 is unrelated
+	// peer3 is unrelated to the route; only its own map can change.
 	result = manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[3]})
-	assert.Empty(t, result)
+	assert.ElementsMatch(t, []string{peerIDs[3]}, result)
 }
 
 func TestResolveAffectedPeers_NetworkRouter(t *testing.T) {
@@ -659,9 +699,13 @@ func TestResolveAffectedPeers_PeerInMultipleGroups(t *testing.T) {
 	}, true)
 	require.NoError(t, err)
 
-	// peer0 is in group0 AND group1, so both policies apply
+	// peer0 is in group0 AND group1, so both policies apply. A peer change folds
+	// only the changed peer plus the opposite side of each rule: group2 (peer2) via
+	// the group0 policy and group3 (peer3) via the group1 policy. peer1, a co-member
+	// of group1, is a sibling of the changed peer and must NOT refresh.
 	result := manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[0]})
-	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[1], peerIDs[2], peerIDs[3]}, result)
+	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[2], peerIDs[3]}, result)
+	assert.NotContains(t, result, peerIDs[1], "co-member of the changed peer's group must not refresh")
 }
 
 func TestResolveAffectedPeers_MultipleChangedPeers(t *testing.T) {
@@ -697,7 +741,7 @@ func TestResolveAffectedPeers_MultipleChangedPeers(t *testing.T) {
 	require.NoError(t, err)
 
 	result := manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[0], peerIDs[2]})
-	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[1], peerIDs[2], peerIDs[3]}, result)
+	assert.ElementsMatch(t, []string{peerIDs[0], peerIDs[2], peerIDs[1], peerIDs[3]}, result)
 }
 
 func TestResolveAffectedPeers_SharedGroupAcrossPolicyAndRoute(t *testing.T) {
@@ -854,8 +898,9 @@ func TestAffectedPeers_IsolatedPolicies(t *testing.T) {
 	assert.NotContains(t, result, peerIDs[0])
 	assert.NotContains(t, result, peerIDs[1])
 
+	// peerIDs[4] is in neither isolated policy; only its own map can change.
 	result = manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[4]})
-	assert.Empty(t, result)
+	assert.ElementsMatch(t, []string{peerIDs[4]}, result)
 }
 
 func TestAffectedPeers_IsolatedRouteAndPolicy(t *testing.T) {
@@ -977,12 +1022,13 @@ func TestAffectedPeers_GroupUpdateOnlyAffectsLinkedPeers(t *testing.T) {
 	})
 }
 
-func TestAffectedPeers_UnlinkedGroupChange_NoUpdates(t *testing.T) {
+// A peer in no policy/route refreshes only itself — no other peer is affected.
+func TestAffectedPeers_UnlinkedPeerChange_RefreshesSelfOnly(t *testing.T) {
 	manager, s, accountID, peerIDs, _ := setupAffectedPeersTest(t)
 	ctx := context.Background()
 
 	result := manager.resolveAffectedPeersForPeerChanges(ctx, s, accountID, []string{peerIDs[0]})
-	assert.Empty(t, result)
+	assert.ElementsMatch(t, []string{peerIDs[0]}, result)
 }
 
 // TestAffectedPeers_PolicyChange_UnrelatedPeerNoUpdate verifies that creating/deleting a

management/server/affectedpeers/resolver.go

@@ -61,7 +61,8 @@ func Load(ctx context.Context, s store.Store, accountID string, c Change) (*Snap
 // loadCollections reads the policy/route/nameserver/dns/router/resource/proxy
 // collections a Change can touch, gated to what the walk needs.
 func (snap *Snapshot) loadCollections(ctx context.Context, s store.Store, accountID string, c Change) error {
-	hasGroupOrPeerChange := len(c.ChangedGroupIDs) > 0 || len(c.ChangedPeerIDs) > 0 || len(c.Resources) > 0
+	// LinkGroups drive the same policy/route/dns walk as a changed group or peer.
+	hasGroupOrPeerChange := len(c.ChangedGroupIDs) > 0 || len(c.ChangedPeerIDs) > 0 || len(c.LinkGroups) > 0 || len(c.Resources) > 0
 	hasNetworkObject := len(c.Routers) > 0 || len(c.Resources) > 0 || len(c.Networks) > 0
 	// the resource<->router bridge can fire for any of these
 	needsRoutersResources := hasGroupOrPeerChange || len(c.PostureCheckIDs) > 0 || len(c.Policies) > 0 || hasNetworkObject
@@ -76,7 +77,7 @@ func (snap *Snapshot) loadCollections(ctx context.Context, s store.Store, accoun
 			return err
 		}
 	}
-	if len(c.ChangedGroupIDs) > 0 || len(c.ChangedPeerIDs) > 0 {
+	if len(c.ChangedGroupIDs) > 0 || len(c.ChangedPeerIDs) > 0 || len(c.LinkGroups) > 0 {
 		if err := snap.loadDNS(ctx, s, accountID); err != nil {
 			return err
 		}
@@ -174,6 +175,24 @@ type Change struct {
 	// folded in — but only when the group is linked (an unlinked group has no map
 	// impact), matching how current members are handled.
 	RemovedPeersByGroup map[string][]string
+
+	// OutputPeerIDs are peers folded straight into the result without seeding their
+	// group memberships into the walk. Use for the peer whose group membership changed:
+	// the peer itself must refresh, but its OTHER groups did not change, so they must
+	// not be walked. Contrast ChangedPeerIDs, which seeds ALL of the peer's groups
+	// (correct when the peer's own attributes changed, e.g. IP/status).
+	OutputPeerIDs []string
+
+	// LinkGroups are groups used ONLY to match policies/routes/routers and walk to the
+	// OPPOSITE side — they are never expanded to their own members. Use this when a
+	// peer's group membership changed: pass the peer in ChangedPeerIDs and its
+	// group(s) here. The opposite side of the policies the group participates in
+	// refreshes, but the group's other members (siblings) do not — nothing changed for
+	// them. For an intra-group policy (A→A) the opposite side IS the group, so its
+	// members still refresh via the opposite-side fold, exactly when they genuinely
+	// gain/lose the changed peer. Unlike ChangedGroupIDs, a LinkGroup is not added to
+	// the output, so a one-sided membership change never wakes the whole group.
+	LinkGroups []string
 }
 
 func (c Change) isEmpty() bool {
@@ -186,7 +205,9 @@ func (c Change) isEmpty() bool {
 		len(c.Networks) == 0 &&
 		len(c.PostureCheckIDs) == 0 &&
 		len(c.DistributionGroupIDs) == 0 &&
-		len(c.RemovedPeersByGroup) == 0
+		len(c.RemovedPeersByGroup) == 0 &&
+		len(c.LinkGroups) == 0 &&
+		len(c.OutputPeerIDs) == 0
 }
 
 // Expand returns the deduplicated affected peer IDs from the preloaded Snapshot,
@@ -197,8 +218,8 @@ func (snap *Snapshot) Expand(ctx context.Context, accountID string, c Change) []
 		return nil
 	}
 	r := newResolver(ctx, snap, accountID, c)
-	log.WithContext(ctx).Tracef("affectedpeers expand start: account=%s changedGroups=%v changedPeers=%v policies=%d routes=%d routers=%d resources=%d networks=%d postureChecks=%v distributionGroups=%v",
-		accountID, c.ChangedGroupIDs, c.ChangedPeerIDs, len(c.Policies), len(c.Routes), len(c.Routers), len(c.Resources), len(c.Networks), c.PostureCheckIDs, c.DistributionGroupIDs)
+	log.WithContext(ctx).Tracef("affectedpeers expand start: account=%s changedGroups=%v changedPeers=%v linkGroups=%v policies=%d routes=%d routers=%d resources=%d networks=%d postureChecks=%v distributionGroups=%v",
+		accountID, c.ChangedGroupIDs, c.ChangedPeerIDs, c.LinkGroups, len(c.Policies), len(c.Routes), len(c.Routers), len(c.Resources), len(c.Networks), c.PostureCheckIDs, c.DistributionGroupIDs)
 	r.walk()
 	return r.expand()
 }
@@ -216,57 +237,84 @@ func Collect(ctx context.Context, s store.Store, accountID string, c Change) (gr
 	}
 	r := newResolver(ctx, snap, accountID, c)
 	r.walk()
-	return setToSlice(r.groupSet), setToSlice(r.peerSet)
+	return setToSlice(r.affectedGroups), setToSlice(r.affectedPeers)
 }
 
 func newResolver(ctx context.Context, snap *Snapshot, accountID string, c Change) *resolver {
 	r := &resolver{
-		ctx:             ctx,
-		snap:            snap,
-		accountID:       accountID,
-		change:          c,
-		changedGroupSet: toSet(c.ChangedGroupIDs),
-		changedPeerSet:  toSet(c.ChangedPeerIDs),
-		groupSet:        make(map[string]struct{}),
-		peerSet:         make(map[string]struct{}),
-		networkIDs:      make(map[string]struct{}),
+		ctx:            ctx,
+		snap:           snap,
+		accountID:      accountID,
+		change:         c,
+		linkGroups:     toSet(c.ChangedGroupIDs),
+		outputGroups:   toSet(c.ChangedGroupIDs),
+		changedPeers:   toSet(c.ChangedPeerIDs),
+		affectedGroups: make(map[string]struct{}),
+		affectedPeers:  make(map[string]struct{}),
 	}
+	// LinkGroups match policies/routes to find the opposite side but are NOT output:
+	// they go into linkGroups only, never outputGroups, so their members never fold in.
+	addAll(r.linkGroups, c.LinkGroups)
 	// Resolve each changed peer to its groups here so callers pass only ChangedPeerIDs.
 	r.seedChangedGroupsFromPeers()
-	r.matchedPolicies = append(r.matchedPolicies, c.Policies...)
 	return r
 }
 
-// seedChangedGroupsFromPeers adds each changed peer's groups to changedGroupSet so
+// seedChangedGroupsFromPeers adds each changed peer's groups to linkGroups so
 // the group-driven walkers fire for memberships, not just direct peer references.
+// These seeded groups are for MATCHING only — folding the changed entity's own
+// side is gated on outputGroups (the caller-reported groups), so a seeded group
+// never folds its whole membership; only the changed peer itself folds in.
 func (r *resolver) seedChangedGroupsFromPeers() {
-	if len(r.changedPeerSet) == 0 {
+	if len(r.changedPeers) == 0 {
 		return
 	}
 	for groupID, members := range r.snap.groupPeers {
-		for pID := range r.changedPeerSet {
+		for pID := range r.changedPeers {
 			if _, ok := members[pID]; ok {
-				r.changedGroupSet[groupID] = struct{}{}
+				r.linkGroups[groupID] = struct{}{}
 				break
 			}
 		}
 	}
 }
 
+// policySide selects which side of a policy rule to walk.
+type policySide int
+
+const (
+	sideSource policySide = iota
+	sideDestination
+)
+
+func (s policySide) opposite() policySide {
+	if s == sideSource {
+		return sideDestination
+	}
+	return sideSource
+}
+
+// walk resolves affected peers in two buckets, by how far each change propagates.
+//
+// BOTH-SIDES — the rule itself changed (an explicit policy edit, or a policy whose
+// posture check changed). Source AND destination refresh, so each such policy is
+// walked on both sides.
+//
+// OPPOSITE-SIDE — an endpoint moved but no rule changed. For each policy the change
+// touches we fold only the side AWAY from the change:
+//   - a changed peer/group sits ON a policy side -> fold the opposite side;
+//   - a changed router/resource/network sits on a NETWORK -> fold the SOURCE side of
+//     the policies whose destination reaches it (and the routers it implies).
+//
+// Routes, nameserver groups, DNS and embedded-proxy services distribute to their own
+// member peers, outside the policy graph, and are folded here too.
 func (r *resolver) walk() {
-	r.collectFromExplicitPolicies()
-	r.collectFromExplicitRoutes(r.change.Routes)
-	r.collectFromExplicitRouters(r.change.Routers)
-	r.collectFromExplicitResources(r.change.Resources)
-	r.collectFromExplicitNetworks(r.change.Networks)
-	r.collectFromPostureChecks(r.change.PostureCheckIDs)
+	for _, policy := range r.bothSidesPolicies() {
+		r.foldPolicySide(policy, sideSource)
+		r.foldPolicySide(policy, sideDestination)
+	}
 
-	// Distribution groups (nameserver/DNS) affect only their member peers: fold them
-	// straight into groupSet so expand() maps them to members, without the policy/
-	// route walk that changedGroupSet would trigger.
-	addAll(r.groupSet, r.change.DistributionGroupIDs)
-
-	if len(r.changedGroupSet) > 0 || len(r.changedPeerSet) > 0 {
+	if len(r.linkGroups) > 0 || len(r.changedPeers) > 0 {
 		r.collectFromPolicies()
 		r.collectFromRoutes()
 		r.collectFromNameServers()
@@ -275,7 +323,31 @@ func (r *resolver) walk() {
 		r.collectFromProxyServices()
 	}
 
-	r.collectResourceRouterBridge()
+	r.collectFromChangedRoutes(r.change.Routes)
+	r.collectFromChangedRouters(r.change.Routers)
+	r.collectFromChangedResources(r.change.Resources)
+	r.collectFromChangedNetworks(r.change.Networks)
+
+	// The explicitly changed peers always refresh their own maps. OnPeersUpdated only
+	// refreshes the resolver's output (it ignores the separately-passed changed peers),
+	// so the changed peer reaches its own new map only via here. An offline/deleted
+	// peer in the set is filtered downstream (filterConnectedAffectedPeers).
+	addAll(r.affectedPeers, setToSlice(r.changedPeers))
+	// OutputPeerIDs refresh themselves too, but unlike changedPeers their group
+	// memberships were not seeded into the walk (only the changed group was).
+	addAll(r.affectedPeers, r.change.OutputPeerIDs)
+
+	// Distribution groups (nameserver/DNS) affect only their member peers: fold them
+	// straight into affectedGroups so expand() maps them to members, without the
+	// policy/route walk that linkGroups would trigger.
+	addAll(r.affectedGroups, r.change.DistributionGroupIDs)
+}
+
+// bothSidesPolicies are the policies whose rule changed: the explicitly edited ones
+// plus those gated by a changed posture check. walk folds both their sides.
+func (r *resolver) bothSidesPolicies() []*types.Policy {
+	policies := append([]*types.Policy(nil), r.change.Policies...)
+	return r.appendPoliciesForPostureChecks(policies, r.change.PostureCheckIDs)
 }
 
 type resolver struct {
@@ -284,14 +356,25 @@ type resolver struct {
 	accountID string
 	change    Change
 
-	changedGroupSet map[string]struct{}
-	changedPeerSet  map[string]struct{}
+	// Inputs — what changed. Set once at construction, read-only during the walk
+	// (except linkGroups, which collectFromExplicitResources also seeds).
+	//
+	// linkGroups is the MATCH set: caller-changed groups ∪ the groups of changed
+	// peers ∪ changed-resource groups. A rule/route/router matches the change when
+	// one of its groups is here — used only to find the opposite side to fold.
+	//
+	// outputGroups is the FOLD-WHOLE-GROUP set: ONLY Change.ChangedGroupIDs. When a
+	// matched group is here, its whole membership is affected. A peer-seeded group
+	// is in linkGroups but NOT outputGroups, so it folds only the changed peer
+	// (changedPeers), never its siblings.
+	linkGroups   map[string]struct{}
+	outputGroups map[string]struct{}
+	changedPeers map[string]struct{}
 
-	groupSet map[string]struct{}
-	peerSet  map[string]struct{}
-
-	matchedPolicies []*types.Policy
-	networkIDs      map[string]struct{}
+	// Outputs — the answer. The only sets the walk accumulates into. affectedGroups
+	// is expanded to its member peers in expand().
+	affectedGroups map[string]struct{}
+	affectedPeers  map[string]struct{}
 }
 
 func (r *resolver) policies() []*types.Policy { return r.snap.policies }
@@ -301,10 +384,10 @@ func (r *resolver) networkResources() []*resourceTypes.NetworkResource { return
 func (r *resolver) networkRouters() []*routerTypes.NetworkRouter { return r.snap.routers }
 
 // peerIDsForGroups maps a group set to its member peer IDs via the preloaded index.
-func (r *resolver) peerIDsForGroups(groupSet map[string]struct{}) []string {
+func (r *resolver) peerIDsForGroups(groups map[string]struct{}) []string {
 	seen := make(map[string]struct{})
 	var ids []string
-	for gID := range groupSet {
+	for gID := range groups {
 		for pID := range r.snap.groupPeers[gID] {
 			if _, ok := seen[pID]; ok {
 				continue
@@ -317,25 +400,25 @@ func (r *resolver) peerIDsForGroups(groupSet map[string]struct{}) []string {
 }
 
 func (r *resolver) expand() []string {
-	peerIDs := r.peerIDsForGroups(r.groupSet)
+	peerIDs := r.peerIDsForGroups(r.affectedGroups)
 
 	log.WithContext(r.ctx).Tracef("affectedpeers expand: account=%s affectedGroups=%v -> %d group-member peers; direct peers=%v",
-		r.accountID, setToSlice(r.groupSet), len(peerIDs), setToSlice(r.peerSet))
+		r.accountID, setToSlice(r.affectedGroups), len(peerIDs), setToSlice(r.affectedPeers))
 
 	seen := make(map[string]struct{}, len(peerIDs))
 	for _, id := range peerIDs {
 		seen[id] = struct{}{}
 	}
-	for id := range r.peerSet {
+	for id := range r.affectedPeers {
 		if _, ok := seen[id]; !ok {
 			peerIDs = append(peerIDs, id)
 			seen[id] = struct{}{}
 		}
 	}
 
-	// Fold in removed peers only when their group is linked (in groupSet).
+	// Fold in removed peers only when their group is linked (in affectedGroups).
 	for groupID, removed := range r.change.RemovedPeersByGroup {
-		if _, linked := r.groupSet[groupID]; !linked {
+		if _, linked := r.affectedGroups[groupID]; !linked {
 			continue
 		}
 		for _, id := range removed {
@@ -351,169 +434,300 @@ func (r *resolver) expand() []string {
 	return peerIDs
 }
 
-func (r *resolver) collectFromExplicitPolicies() {
-	for _, policy := range r.matchedPolicies {
-		if policy == nil {
-			continue
-		}
-		log.WithContext(r.ctx).Tracef("collectFromExplicitPolicies: changed policy %s (%s) -> folding rule groups %v + direct peers",
-			policy.ID, policy.Name, policy.RuleGroups())
-		addAll(r.groupSet, policy.RuleGroups())
-		collectPolicyDirectPeers(policy, r.peerSet)
+// ruleSideGroups / ruleSideResource return the groups and the resource on the given
+// side of a rule.
+func ruleSideGroups(rule *types.PolicyRule, side policySide) []string {
+	if side == sideDestination {
+		return rule.Destinations
 	}
+	return rule.Sources
 }
 
-func (r *resolver) collectFromExplicitRoutes(routes []*route.Route) {
-	for _, rt := range routes {
-		if rt == nil {
-			continue
-		}
-		log.WithContext(r.ctx).Tracef("collectFromExplicitRoutes: changed route %s -> folding groups=%v peerGroups=%v accessControlGroups=%v peer=%q",
-			rt.ID, rt.Groups, rt.PeerGroups, rt.AccessControlGroups, rt.Peer)
-		addAll(r.groupSet, rt.Groups, rt.PeerGroups, rt.AccessControlGroups)
-		if rt.Peer != "" {
-			r.peerSet[rt.Peer] = struct{}{}
-		}
+func ruleSideResource(rule *types.PolicyRule, side policySide) types.Resource {
+	if side == sideDestination {
+		return rule.DestinationResource
 	}
+	return rule.SourceResource
 }
 
-// collectFromExplicitRouters folds changed routers' peers and marks their networks
-// for the bridge. Passing the old router keeps a repointed router's previous peers
-// affected without a post-commit read.
-func (r *resolver) collectFromExplicitRouters(routers []*routerTypes.NetworkRouter) {
-	for _, router := range routers {
-		if router == nil {
-			continue
-		}
-		log.WithContext(r.ctx).Tracef("collectFromExplicitRouters: changed router %s on network %s -> folding peerGroups=%v peer=%q and marking network for source bridge",
-			router.ID, router.NetworkID, router.PeerGroups, router.Peer)
-		addAll(r.groupSet, router.PeerGroups)
-		if router.Peer != "" {
-			r.peerSet[router.Peer] = struct{}{}
-		}
-		if router.NetworkID != "" {
-			r.networkIDs[router.NetworkID] = struct{}{}
-		}
-	}
-}
-
-// collectFromExplicitResources marks changed resources' networks for the bridge and
-// treats their group IDs as changed, so policies targeting the resource via a
-// now-detached (old) group still refresh.
-func (r *resolver) collectFromExplicitResources(resources []*resourceTypes.NetworkResource) {
-	for _, resource := range resources {
-		if resource == nil {
-			continue
-		}
-		log.WithContext(r.ctx).Tracef("collectFromExplicitResources: changed resource %s on network %s -> marking network for bridge and treating groups %v as changed",
-			resource.ID, resource.NetworkID, resource.GroupIDs)
-		addAll(r.changedGroupSet, resource.GroupIDs)
-		if resource.NetworkID != "" {
-			r.networkIDs[resource.NetworkID] = struct{}{}
-		}
-	}
-}
-
-// collectFromExplicitNetworks marks changed networks for the bridge. A network has
-// no groups/peers of its own.
-func (r *resolver) collectFromExplicitNetworks(networks []*networkTypes.Network) {
-	for _, network := range networks {
-		if network == nil {
-			continue
-		}
-		log.WithContext(r.ctx).Tracef("collectFromExplicitNetworks: changed network %s -> marking for bridge", network.ID)
-		if network.ID != "" {
-			r.networkIDs[network.ID] = struct{}{}
-		}
-	}
-}
-
-func (r *resolver) collectFromPostureChecks(postureCheckIDs []string) {
-	if len(postureCheckIDs) == 0 {
+// foldPolicySide folds one side of a policy down to affected peers: its groups
+// (resolved to members in expand) and its direct peer. When the side is the
+// DESTINATION and references a network resource (directly or via a destination
+// group's resources), it also folds the routers that serve that resource's network
+// — a destination resource is reached through its routers. A resource on the SOURCE
+// side routes to nobody (GetPoliciesForNetworkResource matches destinations only),
+// so the router hop is destination-only.
+func (r *resolver) foldPolicySide(policy *types.Policy, side policySide) {
+	if policy == nil {
 		return
 	}
+	for _, rule := range policy.Rules {
+		addAll(r.affectedGroups, ruleSideGroups(rule, side))
+		res := ruleSideResource(rule, side)
+		if res.Type == types.ResourceTypePeer && res.ID != "" {
+			r.affectedPeers[res.ID] = struct{}{}
+		}
+	}
+	if side == sideDestination {
+		r.foldRoutersForResources(r.policyDestinationResourceIDs(policy))
+	}
+}
+
+// appendPoliciesForPostureChecks appends every policy that references a changed
+// posture check (a rule change, so walk both sides).
+func (r *resolver) appendPoliciesForPostureChecks(policies []*types.Policy, postureCheckIDs []string) []*types.Policy {
+	if len(postureCheckIDs) == 0 {
+		return policies
+	}
 	ids := toSet(postureCheckIDs)
 	for _, policy := range r.policies() {
 		if !policyReferencesPostureChecks(policy, ids) {
 			continue
 		}
-		log.WithContext(r.ctx).Tracef("collectFromPostureChecks: policy %s (%s) references changed posture checks %v -> folding rule groups %v + direct peers",
-			policy.ID, policy.Name, postureCheckIDs, policy.RuleGroups())
-		addAll(r.groupSet, policy.RuleGroups())
-		collectPolicyDirectPeers(policy, r.peerSet)
-		r.matchedPolicies = append(r.matchedPolicies, policy)
+		log.WithContext(r.ctx).Tracef("appendPoliciesForPostureChecks: policy %s (%s) references changed posture checks %v -> both-sides policy",
+			policy.ID, policy.Name, postureCheckIDs)
+		policies = append(policies, policy)
+	}
+	return policies
+}
+
+// collectFromPolicies folds, for every policy whose rule a changed group or peer
+// touches, only the OPPOSITE side (down to peers, incl. destination routers), plus
+// the changed entity's own side: the changed group's whole membership when the
+// group itself changed (outputGroups), or the changed peer alone when matched via a
+// peer-seeded group (never its co-members).
+func (r *resolver) collectFromPolicies() {
+	for _, policy := range r.policies() {
+		for _, rule := range policy.Rules {
+			r.foldRuleSideIfChanged(policy, rule, sideSource)
+			r.foldRuleSideIfChanged(policy, rule, sideDestination)
+		}
 	}
 }
 
-func (r *resolver) collectFromPolicies() {
-	for _, policy := range r.policies() {
-		matchedByGroup := policyReferencesGroups(policy, r.changedGroupSet)
-		matchedByPeer := len(r.changedPeerSet) > 0 && policyReferencesDirectPeers(policy, r.changedPeerSet)
-		if !matchedByGroup && !matchedByPeer {
+// foldRuleSideIfChanged: when a changed group or direct peer sits on `side` of the
+// rule, fold the opposite side fully (groups/peers + destination routers) and fold
+// the changed entity's own side (the whole changed group, or the changed peer alone).
+func (r *resolver) foldRuleSideIfChanged(policy *types.Policy, rule *types.PolicyRule, side policySide) {
+	nearGroups := ruleSideGroups(rule, side)
+	nearResource := ruleSideResource(rule, side)
+
+	matchedByGroup := anyInSet(nearGroups, r.linkGroups)
+	matchedByPeer := isDirectPeerInSet(nearResource, r.changedPeers)
+	if !matchedByGroup && !matchedByPeer {
+		return
+	}
+
+	// Opposite side, fully down to peers (a destination opposite also folds routers).
+	r.foldPolicySideForRule(policy, rule, side.opposite())
+
+	// Own side: fold the whole changed group's members only when the group itself
+	// changed (outputGroups). A peer-seeded or link-only group is not folded here —
+	// its siblings never refresh. The changed peers themselves are folded once, after
+	// the walk (see walk()).
+	for _, gID := range nearGroups {
+		if _, ok := r.outputGroups[gID]; ok {
+			r.affectedGroups[gID] = struct{}{}
+		}
+	}
+
+	// When the changed side IS a destination, the resources it targets are reached
+	// through their network's routers, so those routers refresh too (e.g. attaching a
+	// resource to a destination group, or a changed destination group/resource).
+	if side == sideDestination {
+		r.foldRoutersForResources(r.ruleDestinationResourceIDs(rule))
+	}
+}
+
+// foldPolicySideForRule folds one side of a single rule (groups + direct peer), and
+// for a destination side the routers of that rule's destination resources.
+func (r *resolver) foldPolicySideForRule(policy *types.Policy, rule *types.PolicyRule, side policySide) {
+	addAll(r.affectedGroups, ruleSideGroups(rule, side))
+	res := ruleSideResource(rule, side)
+	if res.Type == types.ResourceTypePeer && res.ID != "" {
+		r.affectedPeers[res.ID] = struct{}{}
+	}
+	if side == sideDestination {
+		r.foldRoutersForResources(r.ruleDestinationResourceIDs(rule))
+	}
+}
+
+// collectFromChangedRoutes folds an explicitly changed route's own groups and peer.
+func (r *resolver) collectFromChangedRoutes(routes []*route.Route) {
+	for _, rt := range routes {
+		if rt == nil {
 			continue
 		}
-		log.WithContext(r.ctx).Tracef("collectFromPolicies: policy %s (%s) matched (byGroup=%t byPeer=%t) -> folding rule groups %v + direct peers",
-			policy.ID, policy.Name, matchedByGroup, matchedByPeer, policy.RuleGroups())
-		addAll(r.groupSet, policy.RuleGroups())
-		collectPolicyDirectPeers(policy, r.peerSet)
-		r.matchedPolicies = append(r.matchedPolicies, policy)
+		log.WithContext(r.ctx).Tracef("collectFromChangedRoutes: changed route %s -> folding groups=%v peerGroups=%v accessControlGroups=%v peer=%q",
+			rt.ID, rt.Groups, rt.PeerGroups, rt.AccessControlGroups, rt.Peer)
+		addAll(r.affectedGroups, rt.Groups, rt.PeerGroups, rt.AccessControlGroups)
+		if rt.Peer != "" {
+			r.affectedPeers[rt.Peer] = struct{}{}
+		}
+	}
+}
+
+// collectFromChangedRouters: a changed router refreshes its OWN backing peer/groups
+// (the changed entity) and the SOURCE side of every policy reaching a resource on
+// its network (the router serves the whole network). Sibling routers on the network
+// are independent and are NOT folded. Passing the old router state keeps a repointed
+// router's previous backing affected without a post-commit read.
+func (r *resolver) collectFromChangedRouters(routers []*routerTypes.NetworkRouter) {
+	for _, router := range routers {
+		if router == nil {
+			continue
+		}
+		log.WithContext(r.ctx).Tracef("collectFromChangedRouters: changed router %s on network %s -> folding its own peerGroups=%v peer=%q + sources reaching network resources",
+			router.ID, router.NetworkID, router.PeerGroups, router.Peer)
+		addAll(r.affectedGroups, router.PeerGroups)
+		if router.Peer != "" {
+			r.affectedPeers[router.Peer] = struct{}{}
+		}
+		if router.NetworkID != "" {
+			r.foldPolicySourcesForResources(r.networkResourceIDs(router.NetworkID))
+		}
+	}
+}
+
+// collectFromChangedResources: a changed resource refreshes the SOURCE side of the
+// policies targeting EXACTLY that resource — directly, or via one of the resource's
+// own groups (old∪new across the change, so a now-detached group's sources still
+// refresh) — plus the routers serving its network (the resource is reached through
+// them). It does not touch sibling resources on the same network.
+func (r *resolver) collectFromChangedResources(resources []*resourceTypes.NetworkResource) {
+	for _, resource := range resources {
+		if resource == nil {
+			continue
+		}
+		log.WithContext(r.ctx).Tracef("collectFromChangedResources: changed resource %s on network %s (groups %v) -> folding sources of policies targeting it + its network's routers",
+			resource.ID, resource.NetworkID, resource.GroupIDs)
+		r.foldPolicySourcesForResource(resource.ID, resource.GroupIDs)
+		if resource.NetworkID != "" {
+			r.foldRoutersOnNetworks(map[string]struct{}{resource.NetworkID: {}})
+		}
+	}
+}
+
+// foldPolicySourcesForResource folds the source side of every policy whose
+// destination is the given resource — referenced directly, or via any of the given
+// groups (the resource's own old∪new groups, which captures a detached group).
+func (r *resolver) foldPolicySourcesForResource(resourceID string, groupIDs []string) {
+	groups := toSet(groupIDs)
+	for _, policy := range r.policies() {
+		if !policyTargetsResourceOrGroups(policy, resourceID, groups) {
+			continue
+		}
+		log.WithContext(r.ctx).Tracef("foldPolicySourcesForResource: policy %s (%s) targets changed resource %s -> folding its source groups/peers", policy.ID, policy.Name, resourceID)
+		collectPolicySources(policy, r.affectedGroups, r.affectedPeers)
+	}
+}
+
+// policyTargetsResourceOrGroups reports whether a policy's destination is the given
+// resource directly, or one of the given destination groups.
+func policyTargetsResourceOrGroups(policy *types.Policy, resourceID string, groups map[string]struct{}) bool {
+	if policy == nil {
+		return false
+	}
+	for _, rule := range policy.Rules {
+		if rule.DestinationResource.Type != types.ResourceTypePeer && rule.DestinationResource.ID == resourceID && resourceID != "" {
+			return true
+		}
+		if anyInSet(rule.Destinations, groups) {
+			return true
+		}
+	}
+	return false
+}
+
+// collectFromChangedNetworks: a changed network refreshes the SOURCE side of the
+// policies reaching any of its resources, plus its routers. A network has no
+// groups/peers of its own.
+func (r *resolver) collectFromChangedNetworks(networks []*networkTypes.Network) {
+	for _, network := range networks {
+		if network == nil || network.ID == "" {
+			continue
+		}
+		log.WithContext(r.ctx).Tracef("collectFromChangedNetworks: changed network %s -> folding sources reaching its resources + its routers", network.ID)
+		resourceIDs := r.networkResourceIDs(network.ID)
+		r.foldPolicySourcesForResources(resourceIDs)
+		r.foldRoutersOnNetworks(map[string]struct{}{network.ID: {}})
+	}
+}
+
+// foldPolicySourcesForResources folds the source groups/peers of every policy whose
+// destination targets one of resourceIDs (directly or via a destination group).
+func (r *resolver) foldPolicySourcesForResources(resourceIDs map[string]struct{}) {
+	if len(resourceIDs) == 0 {
+		return
+	}
+	for _, policy := range r.policies() {
+		if r.policyTargetsResources(policy, resourceIDs) {
+			log.WithContext(r.ctx).Tracef("foldPolicySourcesForResources: policy %s (%s) targets a changed resource -> folding its source groups/peers", policy.ID, policy.Name)
+			collectPolicySources(policy, r.affectedGroups, r.affectedPeers)
+		}
 	}
 }
 
 func (r *resolver) collectFromRoutes() {
 	for _, rt := range r.snap.routes {
-		matchedByGroup := anyInSet(rt.Groups, r.changedGroupSet) || anyInSet(rt.PeerGroups, r.changedGroupSet) || anyInSet(rt.AccessControlGroups, r.changedGroupSet)
-		matchedByPeer := rt.Peer != "" && len(r.changedPeerSet) > 0 && isInSet(rt.Peer, r.changedPeerSet)
+		matchedByGroup := anyInSet(rt.Groups, r.linkGroups) || anyInSet(rt.PeerGroups, r.linkGroups) || anyInSet(rt.AccessControlGroups, r.linkGroups)
+		matchedByPeer := rt.Peer != "" && len(r.changedPeers) > 0 && isInSet(rt.Peer, r.changedPeers)
 		if !matchedByGroup && !matchedByPeer {
 			continue
 		}
 		log.WithContext(r.ctx).Tracef("collectFromRoutes: route %s matched (byGroup=%t byPeer=%t) -> folding groups=%v peerGroups=%v accessControlGroups=%v peer=%q",
 			rt.ID, matchedByGroup, matchedByPeer, rt.Groups, rt.PeerGroups, rt.AccessControlGroups, rt.Peer)
-		addAll(r.groupSet, rt.Groups, rt.PeerGroups, rt.AccessControlGroups)
+		addAll(r.affectedGroups, rt.Groups, rt.PeerGroups, rt.AccessControlGroups)
 		if rt.Peer != "" {
-			r.peerSet[rt.Peer] = struct{}{}
+			r.affectedPeers[rt.Peer] = struct{}{}
 		}
 	}
 }
 
 func (r *resolver) collectFromNameServers() {
-	if len(r.changedGroupSet) == 0 {
+	if len(r.linkGroups) == 0 {
 		return
 	}
 	for _, ns := range r.snap.nsGroups {
-		if anyInSet(ns.Groups, r.changedGroupSet) {
+		if anyInSet(ns.Groups, r.linkGroups) {
 			log.WithContext(r.ctx).Tracef("collectFromNameServers: nameserver group %s references a changed group -> folding its groups %v", ns.ID, ns.Groups)
-			addAll(r.groupSet, ns.Groups)
+			addAll(r.affectedGroups, ns.Groups)
 		}
 	}
 }
 
 func (r *resolver) collectFromDNSSettings() {
-	if len(r.changedGroupSet) == 0 || r.snap.dnsSettings == nil {
+	if len(r.linkGroups) == 0 || r.snap.dnsSettings == nil {
 		return
 	}
 	for _, gID := range r.snap.dnsSettings.DisabledManagementGroups {
-		if _, ok := r.changedGroupSet[gID]; ok {
+		if _, ok := r.linkGroups[gID]; ok {
 			log.WithContext(r.ctx).Tracef("collectFromDNSSettings: changed group %s is in DisabledManagementGroups -> folding it", gID)
-			r.groupSet[gID] = struct{}{}
+			r.affectedGroups[gID] = struct{}{}
 		}
 	}
 }
 
+// collectFromNetworkRouters handles a changed group/peer that BACKS a router (the
+// routing peer set moved): the router's own peers refresh and so do the sources of
+// the policies reaching its network's resources. Sibling routers on the network are
+// independent and are not folded.
 func (r *resolver) collectFromNetworkRouters() {
 	for _, router := range r.networkRouters() {
-		matchedByGroup := anyInSet(router.PeerGroups, r.changedGroupSet)
-		matchedByPeer := router.Peer != "" && len(r.changedPeerSet) > 0 && isInSet(router.Peer, r.changedPeerSet)
+		matchedByGroup := anyInSet(router.PeerGroups, r.linkGroups)
+		matchedByPeer := router.Peer != "" && len(r.changedPeers) > 0 && isInSet(router.Peer, r.changedPeers)
 		if !matchedByGroup && !matchedByPeer {
 			continue
 		}
-		log.WithContext(r.ctx).Tracef("collectFromNetworkRouters: router %s on network %s matched (byGroup=%t byPeer=%t) -> folding peerGroups=%v peer=%q and marking network for source bridge",
+		log.WithContext(r.ctx).Tracef("collectFromNetworkRouters: router %s on network %s matched (byGroup=%t byPeer=%t) -> folding its peerGroups=%v peer=%q + sources reaching network resources",
 			router.ID, router.NetworkID, matchedByGroup, matchedByPeer, router.PeerGroups, router.Peer)
-		addAll(r.groupSet, router.PeerGroups)
+		addAll(r.affectedGroups, router.PeerGroups)
 		if router.Peer != "" {
-			r.peerSet[router.Peer] = struct{}{}
+			r.affectedPeers[router.Peer] = struct{}{}
+		}
+		if router.NetworkID != "" {
+			r.foldPolicySourcesForResources(r.networkResourceIDs(router.NetworkID))
 		}
-		r.networkIDs[router.NetworkID] = struct{}{}
 	}
 }
 
@@ -534,34 +748,34 @@ func (r *resolver) collectFromProxyServices() {
 			continue
 		}
 		matchedByPeer := serviceMatchesChangedPeers(svc, proxyPeers, expanded)
-		matchedByAccessGroup := anyInSet(svc.AccessGroups, r.changedGroupSet)
+		matchedByAccessGroup := anyInSet(svc.AccessGroups, r.linkGroups)
 		if !matchedByPeer && !matchedByAccessGroup {
 			continue
 		}
 		log.WithContext(r.ctx).Tracef("collectFromProxyServices: service %s (cluster=%s) matched (byProxyOrTargetPeer=%t byAccessGroup=%t) -> folding %d proxy peers, peer targets and access groups %v",
 			svc.ID, svc.ProxyCluster, matchedByPeer, matchedByAccessGroup, len(proxyPeers), svc.AccessGroups)
 		for _, pid := range proxyPeers {
-			r.peerSet[pid] = struct{}{}
+			r.affectedPeers[pid] = struct{}{}
 		}
 		for _, target := range svc.Targets {
 			if target.TargetType == rpservice.TargetTypePeer && target.TargetId != "" {
-				r.peerSet[target.TargetId] = struct{}{}
+				r.affectedPeers[target.TargetId] = struct{}{}
 			}
 		}
-		addAll(r.groupSet, svc.AccessGroups)
+		addAll(r.affectedGroups, svc.AccessGroups)
 	}
 }
 
 func (r *resolver) expandChangedPeersWithGroups() map[string]struct{} {
-	if len(r.changedGroupSet) == 0 {
-		return r.changedPeerSet
+	if len(r.linkGroups) == 0 {
+		return r.changedPeers
 	}
-	ids := r.peerIDsForGroups(r.changedGroupSet)
+	ids := r.peerIDsForGroups(r.linkGroups)
 	if len(ids) == 0 {
-		return r.changedPeerSet
+		return r.changedPeers
 	}
-	merged := make(map[string]struct{}, len(r.changedPeerSet)+len(ids))
-	for id := range r.changedPeerSet {
+	merged := make(map[string]struct{}, len(r.changedPeers)+len(ids))
+	for id := range r.changedPeers {
 		merged[id] = struct{}{}
 	}
 	for _, id := range ids {
@@ -570,54 +784,36 @@ func (r *resolver) expandChangedPeersWithGroups() map[string]struct{} {
 	return merged
 }
 
-// collectResourceRouterBridge crosses between source peers and routing peers, which
-// are reachable only via resource -> network -> router, not through the policy's own
-// groups: source -> router (targeted resources' networks), then router -> source.
-func (r *resolver) collectResourceRouterBridge() {
-	r.bridgeSourceToRouters()
-	r.bridgeRoutersToSources()
-}
-
-func (r *resolver) bridgeSourceToRouters() {
-	resourceIDs := r.policyDestinationResourceIDs(r.matchedPolicies...)
+// foldRoutersForResources folds the routers serving the networks of the given
+// resources (a destination resource is reached through its network's routers). It is
+// the resource -> network -> router hop used by foldPolicySide for a destination.
+func (r *resolver) foldRoutersForResources(resourceIDs map[string]struct{}) {
 	if len(resourceIDs) == 0 {
 		return
 	}
-
-	networkIDs := r.resourceNetworkIDs(resourceIDs)
-	log.WithContext(r.ctx).Tracef("bridgeSourceToRouters: targeted resources %v -> networks %v (their routers become affected via the router->source pass)",
-		setToSlice(resourceIDs), setToSlice(networkIDs))
-	for id := range networkIDs {
-		r.networkIDs[id] = struct{}{}
-	}
+	r.foldRoutersOnNetworks(r.resourceNetworkIDs(resourceIDs))
 }
 
-func (r *resolver) bridgeRoutersToSources() {
-	if len(r.networkIDs) == 0 {
-		return
+// ruleDestinationResourceIDs returns the destination resource IDs of a single rule:
+// the direct DestinationResource plus the resources of its destination groups.
+func (r *resolver) ruleDestinationResourceIDs(rule *types.PolicyRule) map[string]struct{} {
+	resourceIDs := make(map[string]struct{})
+	if rule.DestinationResource.Type != types.ResourceTypePeer && rule.DestinationResource.ID != "" {
+		resourceIDs[rule.DestinationResource.ID] = struct{}{}
 	}
+	r.addGroupResourceIDs(toSet(rule.Destinations), resourceIDs)
+	return resourceIDs
+}
 
-	log.WithContext(r.ctx).Tracef("bridgeRoutersToSources: affected networks %v -> folding their routing peers and the source peers of policies targeting their resources",
-		setToSlice(r.networkIDs))
-
-	r.foldRoutersOnNetworks(r.networkIDs)
-
+// networkResourceIDs returns the IDs of all resources on the given network.
+func (r *resolver) networkResourceIDs(networkID string) map[string]struct{} {
 	resourceIDs := make(map[string]struct{})
 	for _, resource := range r.networkResources() {
-		if _, ok := r.networkIDs[resource.NetworkID]; ok {
+		if resource.NetworkID == networkID {
 			resourceIDs[resource.ID] = struct{}{}
 		}
 	}
-	if len(resourceIDs) == 0 {
-		return
-	}
-
-	for _, policy := range r.policies() {
-		if r.policyTargetsResources(policy, resourceIDs) {
-			log.WithContext(r.ctx).Tracef("bridgeRoutersToSources: policy %s (%s) targets an affected-network resource -> folding its source groups/peers", policy.ID, policy.Name)
-			collectPolicySources(policy, r.groupSet, r.peerSet)
-		}
-	}
+	return resourceIDs
 }
 
 func (r *resolver) foldRoutersOnNetworks(networkIDs map[string]struct{}) {
@@ -627,9 +823,9 @@ func (r *resolver) foldRoutersOnNetworks(networkIDs map[string]struct{}) {
 		}
 		log.WithContext(r.ctx).Tracef("bridgeRoutersToSources: router %s serves affected network %s -> folding peerGroups=%v peer=%q",
 			router.ID, router.NetworkID, router.PeerGroups, router.Peer)
-		addAll(r.groupSet, router.PeerGroups)
+		addAll(r.affectedGroups, router.PeerGroups)
 		if router.Peer != "" {
-			r.peerSet[router.Peer] = struct{}{}
+			r.affectedPeers[router.Peer] = struct{}{}
 		}
 	}
 }
@@ -714,44 +910,26 @@ func (r *resolver) addGroupResourceIDs(groupIDs map[string]struct{}, resourceIDs
 	}
 }
 
-func collectPolicyDirectPeers(policy *types.Policy, peerSet map[string]struct{}) {
+func collectPolicyDirectPeers(policy *types.Policy, peers map[string]struct{}) {
 	for _, rule := range policy.Rules {
 		if rule.SourceResource.Type == types.ResourceTypePeer && rule.SourceResource.ID != "" {
-			peerSet[rule.SourceResource.ID] = struct{}{}
+			peers[rule.SourceResource.ID] = struct{}{}
 		}
 		if rule.DestinationResource.Type == types.ResourceTypePeer && rule.DestinationResource.ID != "" {
-			peerSet[rule.DestinationResource.ID] = struct{}{}
+			peers[rule.DestinationResource.ID] = struct{}{}
 		}
 	}
 }
 
-func collectPolicySources(policy *types.Policy, groupSet, peerSet map[string]struct{}) {
+func collectPolicySources(policy *types.Policy, groups, peers map[string]struct{}) {
 	for _, rule := range policy.Rules {
-		addAll(groupSet, rule.Sources)
+		addAll(groups, rule.Sources)
 		if rule.SourceResource.Type == types.ResourceTypePeer && rule.SourceResource.ID != "" {
-			peerSet[rule.SourceResource.ID] = struct{}{}
+			peers[rule.SourceResource.ID] = struct{}{}
 		}
 	}
 }
 
-func policyReferencesGroups(policy *types.Policy, groupSet map[string]struct{}) bool {
-	for _, rule := range policy.Rules {
-		if anyInSet(rule.Sources, groupSet) || anyInSet(rule.Destinations, groupSet) {
-			return true
-		}
-	}
-	return false
-}
-
-func policyReferencesDirectPeers(policy *types.Policy, changedSet map[string]struct{}) bool {
-	for _, rule := range policy.Rules {
-		if isDirectPeerInSet(rule.SourceResource, changedSet) || isDirectPeerInSet(rule.DestinationResource, changedSet) {
-			return true
-		}
-	}
-	return false
-}
-
 func policyReferencesPostureChecks(policy *types.Policy, ids map[string]struct{}) bool {
 	for _, id := range policy.SourcePostureChecks {
 		if _, ok := ids[id]; ok {

management/server/affectedpeers/resolver_test.go

@@ -80,26 +80,6 @@ func TestChangeIsEmpty(t *testing.T) {
 	assert.False(t, Change{PostureCheckIDs: []string{"pc"}}.isEmpty())
 }
 
-func TestPolicyReferencesGroups(t *testing.T) {
-	policy := &types.Policy{Rules: []*types.PolicyRule{{Sources: []string{"g1", "g2"}, Destinations: []string{"g3"}}}}
-
-	assert.True(t, policyReferencesGroups(policy, map[string]struct{}{"g1": {}}))
-	assert.True(t, policyReferencesGroups(policy, map[string]struct{}{"g3": {}}))
-	assert.False(t, policyReferencesGroups(policy, map[string]struct{}{"g4": {}}))
-	assert.False(t, policyReferencesGroups(policy, map[string]struct{}{}))
-}
-
-func TestPolicyReferencesDirectPeers(t *testing.T) {
-	policy := &types.Policy{Rules: []*types.PolicyRule{{
-		SourceResource:      types.Resource{Type: types.ResourceTypePeer, ID: "p1"},
-		DestinationResource: types.Resource{Type: types.ResourceTypeHost, ID: "r1"},
-	}}}
-
-	assert.True(t, policyReferencesDirectPeers(policy, map[string]struct{}{"p1": {}}))
-	assert.False(t, policyReferencesDirectPeers(policy, map[string]struct{}{"r1": {}}))
-	assert.False(t, policyReferencesDirectPeers(policy, map[string]struct{}{"p2": {}}))
-}
-
 func TestPolicyReferencesPostureChecks(t *testing.T) {
 	policy := &types.Policy{SourcePostureChecks: []string{"pc1", "pc2"}}
 

management/server/group.go

@@ -520,7 +520,12 @@ func collectDeletableGroups(ctx context.Context, transaction store.Store, accoun
 // GroupAddPeer appends peer to the group
 func (am *DefaultAccountManager) GroupAddPeer(ctx context.Context, accountID, groupID, peerID string) error {
 	var snap *affectedpeers.Snapshot
-	change := affectedpeers.Change{ChangedGroupIDs: []string{groupID}}
+	// A membership change affects only the peer itself and the opposite side of THIS
+	// group's policies — not the group's other members, and not the peer's other
+	// groups. LinkGroups walks only this group (matched, not expanded); OutputPeerIDs
+	// refreshes the peer without seeding its other group memberships. For an
+	// intra-group policy the opposite side is the group, so its members still refresh.
+	change := affectedpeers.Change{OutputPeerIDs: []string{peerID}, LinkGroups: []string{groupID}}
 
 	err := am.Store.ExecuteInTransaction(ctx, func(transaction store.Store) error {
 		if err := transaction.AddPeerToGroup(ctx, accountID, peerID, groupID); err != nil {
@@ -586,10 +591,11 @@ func (am *DefaultAccountManager) GroupAddResource(ctx context.Context, accountID
 // GroupDeletePeer removes peer from the group
 func (am *DefaultAccountManager) GroupDeletePeer(ctx context.Context, accountID, groupID, peerID string) error {
 	var snap *affectedpeers.Snapshot
-	change := affectedpeers.Change{
-		ChangedGroupIDs:     []string{groupID},
-		RemovedPeersByGroup: map[string][]string{groupID: {peerID}},
-	}
+	// Same as GroupAddPeer: the removed peer and the opposite side of THIS group's
+	// policies refresh, not the group's other members or the peer's other groups. The
+	// peer is no longer in the group's index, but LinkGroups still drives the
+	// opposite-side walk, and OutputPeerIDs refreshes the removed peer itself.
+	change := affectedpeers.Change{OutputPeerIDs: []string{peerID}, LinkGroups: []string{groupID}}
 
 	err := am.Store.ExecuteInTransaction(ctx, func(transaction store.Store) error {
 		if err := transaction.RemovePeerFromGroup(ctx, peerID, groupID); err != nil {
@@ -600,8 +606,6 @@ func (am *DefaultAccountManager) GroupDeletePeer(ctx context.Context, accountID,
 			return err
 		}
 
-		// The removed peer is carried in change.RemovedPeersByGroup and folded in
-		// only when the group is linked, so loading post-removal is correct.
 		var err error
 		if snap, err = affectedpeers.Load(ctx, transaction, accountID, change); err != nil {
 			return err