Add default case

client/grpc/dialer_generic.go

@@ -29,7 +29,9 @@ func WithCustomDialer(_ bool, _ string) grpc.DialOption {
 			// the custom dialer requires root permissions which are not required for use cases run as non-root
 			if currentUser.Uid != "0" {
 				log.Debug("Not running as root, using standard dialer")
-				dialer := &net.Dialer{}
+				dialer := &net.Dialer{
+					Resolver: nbnet.NewResolver(),
+				}
 				return dialer.DialContext(ctx, "tcp", addr)
 			}
 		}

client/internal/stdnet/stdnet.go

@@ -18,6 +18,7 @@ import (
 	"github.com/pion/transport/v3/stdnet"
 
 	"github.com/netbirdio/netbird/client/iface/netstack"
+	nbnet "github.com/netbirdio/netbird/client/net"
 )
 
 const (
@@ -42,6 +43,8 @@ type Net struct {
 
 	// ctx is the context for network operations that supports cancellation
 	ctx context.Context
+
+	resolver *net.Resolver
 }
 
 // NewNetWithDiscover creates a new StdNet instance.
@@ -52,6 +55,7 @@ func NewNetWithDiscover(ctx context.Context, iFaceDiscover ExternalIFaceDiscover
 	n := &Net{
 		interfaceFilter: InterfaceFilter(disallowList),
 		ctx:             ctx,
+		resolver:        nbnet.NewResolver(),
 	}
 	// current ExternalIFaceDiscover implement in android-client https://github.dev/netbirdio/android-client
 	// so in android cli use pionDiscover
@@ -72,6 +76,7 @@ func NewNet(ctx context.Context, disallowList []string) (*Net, error) {
 		iFaceDiscover:   pionDiscover{},
 		interfaceFilter: InterfaceFilter(disallowList),
 		ctx:             ctx,
+		resolver:        nbnet.NewResolver(),
 	}
 	return n, n.UpdateInterfaces()
 }
@@ -110,7 +115,7 @@ func (n *Net) resolveAddr(network, address string) (netip.AddrPort, error) {
 	ctx, cancel := context.WithTimeout(n.ctx, dnsResolveTimeout)
 	defer cancel()
 
-	addrs, err := net.DefaultResolver.LookupNetIP(ctx, ipNet, host)
+	addrs, err := n.resolver.LookupNetIP(ctx, ipNet, host)
 	if err != nil {
 		return netip.AddrPort{}, err
 	}

client/net/dialer.go

@@ -13,7 +13,9 @@ type Dialer struct {
 // NewDialer returns a customized net.Dialer with overridden Control method
 func NewDialer() *Dialer {
 	dialer := &Dialer{
-		Dialer: &net.Dialer{},
+		Dialer: &net.Dialer{
+			Resolver: NewResolver(),
+		},
 	}
 	dialer.init()
 	return dialer

client/net/resolver.go

@@ -0,0 +1,47 @@
+package net
+
+import (
+	"net"
+	"os"
+	"runtime"
+	"strings"
+
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	// EnvResolver is the environment variable to control DNS resolver behavior
+	// Values: "system" (use system resolver), "go" (use pure Go resolver), empty (auto-detect)
+	EnvResolver = "NB_DNS_RESOLVER"
+)
+
+// NewResolver creates a DNS resolver with appropriate settings based on platform and configuration.
+// On Darwin (macOS), it defaults to the pure Go resolver to avoid getaddrinfo hangs after sleep/wake.
+// This is particularly important for connections using this package's Dialer, which bypasses the NetBird
+// overlay network for control plane traffic. Since these connections target external infrastructure
+// (management, signal, relay servers), it is safe to ignore split DNS configurations that would
+// normally be provided by the system resolver.
+// On other platforms, it uses the system resolver (cgo).
+// This behavior can be overridden using the NB_DNS_RESOLVER environment variable or GODEBUG.
+func NewResolver() *net.Resolver {
+	if resolver := os.Getenv(EnvResolver); resolver != "" {
+		switch strings.ToLower(resolver) {
+		case "system":
+			return net.DefaultResolver
+		case "go":
+			return &net.Resolver{
+				PreferGo: true,
+			}
+		default:
+			log.Debugf("Invalid %s value: %s, using platform defaults", EnvResolver, resolver)
+		}
+	}
+
+	if runtime.GOOS == "darwin" {
+		return &net.Resolver{
+			PreferGo: true,
+		}
+	}
+
+	return net.DefaultResolver
+}