Add DNS configuration snapshot and per-domain statistics tracking

Some features can only be manipulated via environment variables. With this PR, environment variables can be managed from Android.

client/android/client.go

@@ -4,6 +4,7 @@ package android
 
 import (
 	"context"
+	"os"
 	"slices"
 	"sync"
 
@@ -83,7 +84,8 @@ func NewClient(cfgFile string, androidSDKVersion int, deviceName string, uiVersi
 }
 
 // Run start the internal client. It is a blocker function
-func (c *Client) Run(urlOpener URLOpener, dns *DNSList, dnsReadyListener DnsReadyListener) error {
+func (c *Client) Run(urlOpener URLOpener, dns *DNSList, dnsReadyListener DnsReadyListener, envList *EnvList) error {
+	exportEnvList(envList)
 	cfg, err := profilemanager.UpdateOrCreateConfig(profilemanager.ConfigInput{
 		ConfigPath: c.cfgFile,
 	})
@@ -118,7 +120,8 @@ func (c *Client) Run(urlOpener URLOpener, dns *DNSList, dnsReadyListener DnsRead
 
 // RunWithoutLogin we apply this type of run function when the backed has been started without UI (i.e. after reboot).
 // In this case make no sense handle registration steps.
-func (c *Client) RunWithoutLogin(dns *DNSList, dnsReadyListener DnsReadyListener) error {
+func (c *Client) RunWithoutLogin(dns *DNSList, dnsReadyListener DnsReadyListener, envList *EnvList) error {
+	exportEnvList(envList)
 	cfg, err := profilemanager.UpdateOrCreateConfig(profilemanager.ConfigInput{
 		ConfigPath: c.cfgFile,
 	})
@@ -249,3 +252,14 @@ func (c *Client) SetConnectionListener(listener ConnectionListener) {
 func (c *Client) RemoveConnectionListener() {
 	c.recorder.RemoveConnectionListener()
 }
+
+func exportEnvList(list *EnvList) {
+	if list == nil {
+		return
+	}
+	for k, v := range list.AllItems() {
+		if err := os.Setenv(k, v); err != nil {
+			log.Errorf("could not set env variable %s: %v", k, err)
+		}
+	}
+}

client/android/env_list.go

@@ -0,0 +1,32 @@
+package android
+
+import "github.com/netbirdio/netbird/client/internal/peer"
+
+var (
+	// EnvKeyNBForceRelay Exported for Android java client
+	EnvKeyNBForceRelay = peer.EnvKeyNBForceRelay
+)
+
+// EnvList wraps a Go map for export to Java
+type EnvList struct {
+	data map[string]string
+}
+
+// NewEnvList creates a new EnvList
+func NewEnvList() *EnvList {
+	return &EnvList{data: make(map[string]string)}
+}
+
+// Put adds a key-value pair
+func (el *EnvList) Put(key, value string) {
+	el.data[key] = value
+}
+
+// Get retrieves a value by key
+func (el *EnvList) Get(key string) string {
+	return el.data[key]
+}
+
+func (el *EnvList) AllItems() map[string]string {
+	return el.data
+}

client/cmd/debug.go

@@ -388,12 +388,12 @@ func generateDebugBundle(config *profilemanager.Config, recorder *peer.Status, c
 }
 
 func init() {
-	debugBundleCmd.Flags().Uint32VarP(&logFileCount, "log-file-count", "C", 1, "Number of rotated log files to include in debug bundle")
+	debugBundleCmd.Flags().Uint32VarP(&logFileCount, "log-file-count", "C", 10, "Number of rotated log files to include in debug bundle")
 	debugBundleCmd.Flags().BoolVarP(&systemInfoFlag, "system-info", "S", true, "Adds system information to the debug bundle")
 	debugBundleCmd.Flags().BoolVarP(&uploadBundleFlag, "upload-bundle", "U", false, "Uploads the debug bundle to a server")
 	debugBundleCmd.Flags().StringVar(&uploadBundleURLFlag, "upload-bundle-url", types.DefaultBundleURL, "Service URL to get an URL to upload the debug bundle")
 
-	forCmd.Flags().Uint32VarP(&logFileCount, "log-file-count", "C", 1, "Number of rotated log files to include in debug bundle")
+	forCmd.Flags().Uint32VarP(&logFileCount, "log-file-count", "C", 10, "Number of rotated log files to include in debug bundle")
 	forCmd.Flags().BoolVarP(&systemInfoFlag, "system-info", "S", true, "Adds system information to the debug bundle")
 	forCmd.Flags().BoolVarP(&uploadBundleFlag, "upload-bundle", "U", false, "Uploads the debug bundle to a server")
 	forCmd.Flags().StringVar(&uploadBundleURLFlag, "upload-bundle-url", types.DefaultBundleURL, "Service URL to get an URL to upload the debug bundle")

client/internal/debug/debug.go

@@ -315,6 +315,10 @@ func (g *BundleGenerator) createArchive() error {
 		return fmt.Errorf("add sync response: %w", err)
 	}
 
+	if err := g.addDNSConfig(); err != nil {
+		log.Errorf("failed to add DNS config to debug bundle: %v", err)
+	}
+
 	if err := g.addStateFile(); err != nil {
 		log.Errorf("failed to add state file to debug bundle: %v", err)
 	}
@@ -341,6 +345,50 @@ func (g *BundleGenerator) createArchive() error {
 	return nil
 }
 
+// addDNSConfig writes a dns_config.json snapshot with routed domains and NS group status
+func (g *BundleGenerator) addDNSConfig() error {
+	type nsGroup struct {
+		ID      string   `json:"id"`
+		Servers []string `json:"servers"`
+		Domains []string `json:"domains"`
+		Enabled bool     `json:"enabled"`
+		Error   string   `json:"error,omitempty"`
+	}
+	type dnsConfig struct {
+		Groups []nsGroup `json:"name_server_groups"`
+	}
+
+	if g.statusRecorder == nil {
+		return nil
+	}
+
+	states := g.statusRecorder.GetDNSStates()
+	cfg := dnsConfig{Groups: make([]nsGroup, 0, len(states))}
+	for _, st := range states {
+		var servers []string
+		for _, ap := range st.Servers {
+			servers = append(servers, ap.String())
+		}
+		var errStr string
+		if st.Error != nil {
+			errStr = st.Error.Error()
+		}
+		cfg.Groups = append(cfg.Groups, nsGroup{
+			ID:      st.ID,
+			Servers: servers,
+			Domains: st.Domains,
+			Enabled: st.Enabled,
+			Error:   errStr,
+		})
+	}
+
+	bs, err := json.MarshalIndent(cfg, "", "  ")
+	if err != nil {
+		return fmt.Errorf("marshal dns config: %w", err)
+	}
+	return g.addFileToZip(bytes.NewReader(bs), "dns_config.json")
+}
+
 func (g *BundleGenerator) addSystemInfo() {
 	if err := g.addRoutes(); err != nil {
 		log.Errorf("failed to add routes to debug bundle: %v", err)

client/internal/dnsfwd/forwarder.go

@@ -46,6 +46,18 @@ type DNSForwarder struct {
 	fwdEntries []*ForwarderEntry
 	firewall   firewaller
 	resolver   resolver
+
+	// failure rate tracking for routed domains
+	failureMu      sync.Mutex
+	failureCounts  map[string]int
+	failureWindow  time.Duration
+	lastLogPerHost map[string]time.Time
+
+	// per-domain rolling stats and windows
+	statsMu sync.Mutex
+	stats   map[string]*domainStats
+	winSize time.Duration
+	slowT   time.Duration
 }
 
 func NewDNSForwarder(listenAddress string, ttl uint32, firewall firewaller, statusRecorder *peer.Status) *DNSForwarder {
@@ -56,9 +68,25 @@ func NewDNSForwarder(listenAddress string, ttl uint32, firewall firewaller, stat
 		firewall:       firewall,
 		statusRecorder: statusRecorder,
 		resolver:       net.DefaultResolver,
+		failureCounts:  make(map[string]int),
+		failureWindow:  10 * time.Second,
+		lastLogPerHost: make(map[string]time.Time),
+		stats:          make(map[string]*domainStats),
+		winSize:        10 * time.Second,
+		slowT:          300 * time.Millisecond,
 	}
 }
 
+type domainStats struct {
+	total    int
+	success  int
+	timeouts int
+	notfound int
+	failures int // other failures (incl. SERVFAIL-like)
+	slow     int
+	lastLog  time.Time
+}
+
 func (f *DNSForwarder) Listen(entries []*ForwarderEntry) error {
 	log.Infof("starting DNS forwarder on address=%s", f.listenAddress)
 
@@ -163,12 +191,19 @@ func (f *DNSForwarder) handleDNSQuery(w dns.ResponseWriter, query *dns.Msg) *dns
 
 	ctx, cancel := context.WithTimeout(context.Background(), upstreamTimeout)
 	defer cancel()
+	start := time.Now()
 	ips, err := f.resolver.LookupNetIP(ctx, network, domain)
+	elapsed := time.Since(start)
 	if err != nil {
 		f.handleDNSError(ctx, w, question, resp, domain, err)
+		// record error stats for routed domains
+		f.recordErrorStats(strings.TrimSuffix(domain, "."), err)
 		return nil
 	}
 
+	// record success timing
+	f.recordSuccessStats(strings.TrimSuffix(domain, "."), elapsed)
+
 	f.updateInternalState(ips, mostSpecificResId, matchingEntries)
 	f.addIPsToResponse(resp, domain, ips)
 
@@ -306,6 +341,91 @@ func (f *DNSForwarder) handleDNSError(ctx context.Context, w dns.ResponseWriter,
 	if err := w.WriteMsg(resp); err != nil {
 		log.Errorf("failed to write failure DNS response: %v", err)
 	}
+
+	// Track failure rate for routed domains only
+	if resID, _ := f.getMatchingEntries(strings.TrimSuffix(domain, ".")); resID != "" {
+		f.recordDomainFailure(strings.TrimSuffix(domain, "."))
+	}
+}
+
+// recordErrorStats updates per-domain counters and emits rate-limited logs
+func (f *DNSForwarder) recordErrorStats(domain string, err error) {
+	domain = strings.ToLower(domain)
+	f.statsMu.Lock()
+	s := f.ensureStats(domain)
+	s.total++
+
+	var dnsErr *net.DNSError
+	if errors.As(err, &dnsErr) {
+		if dnsErr.IsNotFound {
+			s.notfound++
+		} else if dnsErr.Timeout() {
+			s.timeouts++
+		} else {
+			s.failures++
+		}
+	} else {
+		s.failures++
+	}
+
+	f.maybeLogDomainStats(domain, s)
+	f.statsMu.Unlock()
+}
+
+// recordSuccessStats updates per-domain latency stats and slow counters, logs if needed (rate-limited)
+func (f *DNSForwarder) recordSuccessStats(domain string, elapsed time.Duration) {
+	domain = strings.ToLower(domain)
+	f.statsMu.Lock()
+	s := f.ensureStats(domain)
+	s.total++
+	s.success++
+	if elapsed >= f.slowT {
+		s.slow++
+	}
+	f.maybeLogDomainStats(domain, s)
+	f.statsMu.Unlock()
+}
+
+func (f *DNSForwarder) ensureStats(domain string) *domainStats {
+	if ds, ok := f.stats[domain]; ok {
+		return ds
+	}
+	ds := &domainStats{}
+	f.stats[domain] = ds
+	return ds
+}
+
+// maybeLogDomainStats logs a compact summary per routed domain at most once per window
+func (f *DNSForwarder) maybeLogDomainStats(domain string, s *domainStats) {
+	now := time.Now()
+	if !s.lastLog.IsZero() && now.Sub(s.lastLog) < f.winSize {
+		return
+	}
+
+	// check if routed (avoid logging for non-routed domains)
+	if resID, _ := f.getMatchingEntries(domain); resID == "" {
+		return
+	}
+
+	// only log if something noteworthy happened in the window
+	noteworthy := s.timeouts > 0 || s.notfound > 0 || s.failures > 0 || s.slow > 0
+	if !noteworthy {
+		s.lastLog = now
+		return
+	}
+
+	// warn on persistent problems, info otherwise
+	levelWarn := s.timeouts >= 3 || s.failures >= 3
+	if levelWarn {
+		log.Warnf("[d] DNS stats: domain=%s total=%d ok=%d timeout=%d nxdomain=%d fail=%d slow=%d(>=%s)",
+			domain, s.total, s.success, s.timeouts, s.notfound, s.failures, s.slow, f.slowT)
+	} else {
+		log.Infof("[d] DNS stats: domain=%s total=%d ok=%d timeout=%d nxdomain=%d fail=%d slow=%d(>=%s)",
+			domain, s.total, s.success, s.timeouts, s.notfound, s.failures, s.slow, f.slowT)
+	}
+
+	// reset counters for next window
+	*s = domainStats{lastLog: now}
 }
 
 // addIPsToResponse adds IP addresses to the DNS response as appropriate A or AAAA records
@@ -341,6 +461,27 @@ func (f *DNSForwarder) addIPsToResponse(resp *dns.Msg, domain string, ips []neti
 	}
 }
 
+// recordDomainFailure increments failure count for the domain and logs at info/warn with throttling.
+func (f *DNSForwarder) recordDomainFailure(domain string) {
+	domain = strings.ToLower(domain)
+
+	f.failureMu.Lock()
+	defer f.failureMu.Unlock()
+
+	f.failureCounts[domain]++
+	count := f.failureCounts[domain]
+
+	now := time.Now()
+	last, ok := f.lastLogPerHost[domain]
+	if ok && now.Sub(last) < f.failureWindow {
+		return
+	}
+	f.lastLogPerHost[domain] = now
+
+	log.Warnf("[d] DNS failures observed for routed domain: domain=%s failures=%d/%s", domain, count, f.failureWindow)
+
+}
+
 // getMatchingEntries retrieves the resource IDs for a given domain.
 // It returns the most specific match and all matching resource IDs.
 func (f *DNSForwarder) getMatchingEntries(domain string) (route.ResID, []*ForwarderEntry) {

client/internal/peer/conn.go

@@ -6,7 +6,6 @@ import (
 	"math/rand"
 	"net"
 	"net/netip"
-	"os"
 	"runtime"
 	"sync"
 	"time"
@@ -174,7 +173,7 @@ func (conn *Conn) Open(engineCtx context.Context) error {
 	conn.handshaker = NewHandshaker(conn.Log, conn.config, conn.signaler, conn.workerICE, conn.workerRelay)
 
 	conn.handshaker.AddOnNewOfferListener(conn.workerRelay.OnNewOffer)
-	if os.Getenv("NB_FORCE_RELAY") != "true" {
+	if !isForceRelayed() {
 		conn.handshaker.AddOnNewOfferListener(conn.workerICE.OnNewOffer)
 	}
 

client/internal/peer/env.go

@@ -0,0 +1,14 @@
+package peer
+
+import (
+	"os"
+	"strings"
+)
+
+const (
+	EnvKeyNBForceRelay = "NB_FORCE_RELAY"
+)
+
+func isForceRelayed() bool {
+	return strings.EqualFold(os.Getenv(EnvKeyNBForceRelay), "true")
+}

client/internal/peer/status.go

@@ -21,9 +21,9 @@ import (
 	"github.com/netbirdio/netbird/client/internal/ingressgw"
 	"github.com/netbirdio/netbird/client/internal/relay"
 	"github.com/netbirdio/netbird/client/proto"
+	"github.com/netbirdio/netbird/route"
 	"github.com/netbirdio/netbird/shared/management/domain"
 	relayClient "github.com/netbirdio/netbird/shared/relay/client"
-	"github.com/netbirdio/netbird/route"
 )
 
 const eventQueueSize = 10
@@ -201,6 +201,8 @@ type Status struct {
 	resolvedDomainsStates map[domain.Domain]ResolvedDomainInfo
 	lazyConnectionEnabled bool
 
+	lastDisconnectLog map[string]time.Time
+
 	// To reduce the number of notification invocation this bool will be true when need to call the notification
 	// Some Peer actions mostly used by in a batch when the network map has been synchronized. In these type of events
 	// set to true this variable and at the end of the processing we will reset it by the FinishPeerListModifications()
@@ -229,6 +231,7 @@ func NewRecorder(mgmAddress string) *Status {
 		notifier:              newNotifier(),
 		mgmAddress:            mgmAddress,
 		resolvedDomainsStates: map[domain.Domain]ResolvedDomainInfo{},
+		lastDisconnectLog:     make(map[string]time.Time),
 	}
 }
 
@@ -487,6 +490,9 @@ func (d *Status) UpdatePeerRelayedStateToDisconnected(receivedState State) error
 
 	d.peers[receivedState.PubKey] = peerState
 
+	// info log about disconnect with impacted routes (throttled)
+	d.logPeerDisconnectIfNeeded(receivedState.PubKey, peerState)
+
 	if hasConnStatusChanged(oldState, receivedState.ConnStatus) {
 		d.notifyPeerListChanged()
 	}
@@ -519,6 +525,9 @@ func (d *Status) UpdatePeerICEStateToDisconnected(receivedState State) error {
 
 	d.peers[receivedState.PubKey] = peerState
 
+	// info log about disconnect with impacted routes (throttled)
+	d.logPeerDisconnectIfNeeded(receivedState.PubKey, peerState)
+
 	if hasConnStatusChanged(oldState, receivedState.ConnStatus) {
 		d.notifyPeerListChanged()
 	}
@@ -529,6 +538,49 @@ func (d *Status) UpdatePeerICEStateToDisconnected(receivedState State) error {
 	return nil
 }
 
+// logPeerDisconnectIfNeeded logs an info message when a routing peer transitions to disconnected
+// with the number of impacted routes. Throttled to once per peer per 30 seconds.
+func (d *Status) logPeerDisconnectIfNeeded(pubKey string, state State) {
+	if state.ConnStatus != StatusIdle {
+		return
+	}
+
+	now := time.Now()
+	last, ok := d.lastDisconnectLog[pubKey]
+	if ok && now.Sub(last) < 10*time.Second {
+		return
+	}
+	d.lastDisconnectLog[pubKey] = now
+
+	routes := state.GetRoutes()
+	numRoutes := len(routes)
+
+	fqdn := state.FQDN
+	if fqdn == "" {
+		fqdn = pubKey
+	}
+
+	// prepare a bounded list of impacted routes to avoid huge log lines
+	maxList := 20
+	list := make([]string, 0, maxList)
+	for r := range routes {
+		if len(list) >= maxList {
+			break
+		}
+		list = append(list, r)
+	}
+	more := ""
+	if numRoutes > len(list) {
+		more = ", more=" + fmt.Sprintf("%d", numRoutes-len(list))
+	}
+
+	if len(list) > 0 {
+		log.Warnf("[d] Routing peer disconnected: peer=%s impacted_routes=%d routes=%v%s", fqdn, numRoutes, list, more)
+	} else {
+		log.Warnf("[d] Routing peer disconnected: peer=%s impacted_routes=%d", fqdn, numRoutes)
+	}
+}
+
 // UpdateWireGuardPeerState updates the WireGuard bits of the peer state
 func (d *Status) UpdateWireGuardPeerState(pubKey string, wgStats configurer.WGStats) error {
 	d.mux.Lock()

util/log.go

@@ -14,7 +14,7 @@ import (
 	"github.com/netbirdio/netbird/formatter"
 )
 
-const defaultLogSize = 15
+const defaultLogSize = 100
 
 const (
 	LogConsole = "console"