transport should try ipv4 then ipv6 explicitly

client list panic guards and debug logging

cmd/cli/commands.go

@@ -1273,7 +1273,8 @@ func initUpgradeCmd() *cobra.Command {
 			}
 			dlUrl := upgradeUrl(baseUrl)
 			mainLog.Load().Debug().Msgf("Downloading binary: %s", dlUrl)
-			resp, err := http.Get(dlUrl)
+
+			resp, err := getWithRetry(dlUrl)
 			if err != nil {
 				mainLog.Load().Fatal().Err(err).Msg("failed to download binary")
 			}

cmd/cli/control_server.go

@@ -79,33 +79,81 @@ func (s *controlServer) register(pattern string, handler http.Handler) {
 
 func (p *prog) registerControlServerHandler() {
 	p.cs.register(listClientsPath, http.HandlerFunc(func(w http.ResponseWriter, request *http.Request) {
+		mainLog.Load().Debug().Msg("handling list clients request")
+
 		clients := p.ciTable.ListClients()
+		mainLog.Load().Debug().Int("client_count", len(clients)).Msg("retrieved clients list")
+
 		sort.Slice(clients, func(i, j int) bool {
 			return clients[i].IP.Less(clients[j].IP)
 		})
+		mainLog.Load().Debug().Msg("sorted clients by IP address")
+
 		if p.metricsQueryStats.Load() {
-			for _, client := range clients {
+			mainLog.Load().Debug().Msg("metrics query stats enabled, collecting query counts")
+
+			for idx, client := range clients {
+				mainLog.Load().Debug().
+					Int("index", idx).
+					Str("ip", client.IP.String()).
+					Str("mac", client.Mac).
+					Str("hostname", client.Hostname).
+					Msg("processing client metrics")
+
 				client.IncludeQueryCount = true
 				dm := &dto.Metric{}
+
+				if statsClientQueriesCount.MetricVec == nil {
+					mainLog.Load().Debug().
+						Str("client_ip", client.IP.String()).
+						Msg("skipping metrics collection: MetricVec is nil")
+					continue
+				}
+
 				m, err := statsClientQueriesCount.MetricVec.GetMetricWithLabelValues(
 					client.IP.String(),
 					client.Mac,
 					client.Hostname,
 				)
 				if err != nil {
-					mainLog.Load().Debug().Err(err).Msgf("could not get metrics for client: %v", client)
+					mainLog.Load().Debug().
+						Err(err).
+						Str("client_ip", client.IP.String()).
+						Str("mac", client.Mac).
+						Str("hostname", client.Hostname).
+						Msg("failed to get metrics for client")
 					continue
 				}
-				if err := m.Write(dm); err == nil {
+
+				if err := m.Write(dm); err == nil && dm.Counter != nil {
 					client.QueryCount = int64(dm.Counter.GetValue())
+					mainLog.Load().Debug().
+						Str("client_ip", client.IP.String()).
+						Int64("query_count", client.QueryCount).
+						Msg("successfully collected query count")
+				} else if err != nil {
+					mainLog.Load().Debug().
+						Err(err).
+						Str("client_ip", client.IP.String()).
+						Msg("failed to write metric")
 				}
 			}
+		} else {
+			mainLog.Load().Debug().Msg("metrics query stats disabled, skipping query counts")
 		}
 
 		if err := json.NewEncoder(w).Encode(&clients); err != nil {
+			mainLog.Load().Error().
+				Err(err).
+				Int("client_count", len(clients)).
+				Msg("failed to encode clients response")
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
+
+		mainLog.Load().Debug().
+			Int("client_count", len(clients)).
+			Msg("successfully sent clients list response")
 	}))
 	p.cs.register(startedPath, http.HandlerFunc(func(w http.ResponseWriter, request *http.Request) {
 		select {

cmd/cli/library.go

@@ -1,5 +1,12 @@
 package cli
 
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"time"
+)
+
 // AppCallback provides hooks for injecting certain functionalities
 // from mobile platforms to main ctrld cli.
 type AppCallback struct {
@@ -17,3 +24,55 @@ type AppConfig struct {
 	Verbose       int
 	LogPath       string
 }
+
+const (
+	defaultHTTPTimeout = 30 * time.Second
+	defaultMaxRetries  = 3
+)
+
+// httpClientWithFallback returns an HTTP client configured with timeout and IPv4 fallback
+func httpClientWithFallback(timeout time.Duration) *http.Client {
+	return &http.Client{
+		Timeout: timeout,
+		Transport: &http.Transport{
+			// Prefer IPv4 over IPv6
+			DialContext: (&net.Dialer{
+				Timeout:       10 * time.Second,
+				KeepAlive:     30 * time.Second,
+				FallbackDelay: 1 * time.Millisecond, // Very small delay to prefer IPv4
+			}).DialContext,
+		},
+	}
+}
+
+// doWithRetry performs an HTTP request with retries
+func doWithRetry(req *http.Request, maxRetries int) (*http.Response, error) {
+	var lastErr error
+	client := httpClientWithFallback(defaultHTTPTimeout)
+
+	for attempt := 0; attempt < maxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(time.Second * time.Duration(attempt+1)) // Exponential backoff
+		}
+
+		resp, err := client.Do(req)
+		if err == nil {
+			return resp, nil
+		}
+		lastErr = err
+		mainLog.Load().Debug().Err(err).
+			Str("method", req.Method).
+			Str("url", req.URL.String()).
+			Msgf("HTTP request attempt %d/%d failed", attempt+1, maxRetries)
+	}
+	return nil, fmt.Errorf("failed after %d attempts to %s %s: %v", maxRetries, req.Method, req.URL, lastErr)
+}
+
+// Helper for making GET requests with retries
+func getWithRetry(url string) (*http.Response, error) {
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		return nil, err
+	}
+	return doWithRetry(req, defaultMaxRetries)
+}

cmd/cli/service.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"runtime"
 
 	"github.com/kardianos/service"
 
@@ -168,7 +169,11 @@ func doTasks(tasks []task) bool {
 				mainLog.Load().Error().Msgf("error running task %s: %v", task.Name, err)
 				return false
 			}
-			mainLog.Load().Debug().Msgf("error running task %s: %v", task.Name, err)
+			// if this is darwin stop command, dont print debug
+			// since launchctl complains on every start
+			if runtime.GOOS != "darwin" || task.Name != "Stop" {
+				mainLog.Load().Debug().Msgf("error running task %s: %v", task.Name, err)
+			}
 		}
 	}
 	return true

internal/clientinfo/client_info.go

@@ -422,17 +422,27 @@ func (t *Table) ListClients() []*Client {
 	t.Refresh()
 	ipMap := make(map[string]*Client)
 	il := []ipLister{t.dhcp, t.arp, t.ndp, t.ptr, t.mdns, t.vni}
+
 	for _, ir := range il {
+		if ir == nil {
+			continue
+		}
+
 		for _, ip := range ir.List() {
-			c, ok := ipMap[ip]
-			if !ok {
-				c = &Client{
-					IP:     netip.MustParseAddr(ip),
-					Source: map[string]struct{}{ir.String(): {}},
+			// Validate IP before using MustParseAddr
+			if addr, err := netip.ParseAddr(ip); err == nil {
+				c, ok := ipMap[ip]
+				if !ok {
+					c = &Client{
+						IP:     addr,
+						Source: map[string]struct{}{},
+					}
+					ipMap[ip] = c
+				}
+				// Safely get source name
+				if src := ir.String(); src != "" {
+					c.Source[src] = struct{}{}
 				}
-				ipMap[ip] = c
-			} else {
-				c.Source[ir.String()] = struct{}{}
 			}
 		}
 	}

internal/controld/config.go

@@ -216,19 +216,55 @@ func apiTransport(cdDev bool) *http.Transport {
 		if cdDev {
 			apiDomain = apiDomainDev
 		}
+
+		// First try IPv4
+		dialer := &net.Dialer{
+			Timeout:   10 * time.Second,
+			KeepAlive: 30 * time.Second,
+		}
+
 		ips := ctrld.LookupIP(apiDomain)
 		if len(ips) == 0 {
-			ctrld.ProxyLogger.Load().Warn().Msgf("No IPs found for %s, connecting to %s", apiDomain, addr)
-			return ctrldnet.Dialer.DialContext(ctx, network, addr)
+			ctrld.ProxyLogger.Load().Warn().Msgf("No IPs found for %s, falling back to direct connection to %s", apiDomain, addr)
+			return dialer.DialContext(ctx, network, addr)
 		}
-		ctrld.ProxyLogger.Load().Debug().Msgf("API IPs: %v", ips)
+
+		// Separate IPv4 and IPv6 addresses
+		var ipv4s, ipv6s []string
+		for _, ip := range ips {
+			if strings.Contains(ip, ":") {
+				ipv6s = append(ipv6s, ip)
+			} else {
+				ipv4s = append(ipv4s, ip)
+			}
+		}
+
 		_, port, _ := net.SplitHostPort(addr)
-		addrs := make([]string, len(ips))
-		for i := range ips {
-			addrs[i] = net.JoinHostPort(ips[i], port)
+
+		// Try IPv4 first
+		if len(ipv4s) > 0 {
+			addrs := make([]string, len(ipv4s))
+			for i, ip := range ipv4s {
+				addrs[i] = net.JoinHostPort(ip, port)
+			}
+			d := &ctrldnet.ParallelDialer{}
+			if conn, err := d.DialContext(ctx, "tcp4", addrs, ctrld.ProxyLogger.Load()); err == nil {
+				return conn, nil
+			}
 		}
-		d := &ctrldnet.ParallelDialer{}
-		return d.DialContext(ctx, network, addrs, ctrld.ProxyLogger.Load())
+
+		// Fall back to IPv6 if available
+		if len(ipv6s) > 0 {
+			addrs := make([]string, len(ipv6s))
+			for i, ip := range ipv6s {
+				addrs[i] = net.JoinHostPort(ip, port)
+			}
+			d := &ctrldnet.ParallelDialer{}
+			return d.DialContext(ctx, "tcp6", addrs, ctrld.ProxyLogger.Load())
+		}
+
+		// Final fallback to direct connection
+		return dialer.DialContext(ctx, network, addr)
 	}
 	if router.Name() == ddwrt.Name || runtime.GOOS == "android" {
 		transport.TLSClientConfig = &tls.Config{RootCAs: certs.CACertPool()}