Make errors less scary

hack/test-templates.sh

@@ -339,7 +339,7 @@ if [[ -n ${CHECKS["ssh-over-vsock"]} ]]; then
 		INFO "Testing .ssh.overVsock=true configuration"
 		limactl stop "${NAME}"
 		# Detection of the SSH server on VSOCK may fail; however, a failing log indicates that controlling detection via the environment variable works as expected.
-		if ! limactl start --set '.ssh.overVsock=true' "${NAME}" 2>&1 | grep -i -E "(started vsock forwarder|Failed to detect SSH server on vsock)"; then
+		if ! limactl start --set '.ssh.overVsock=true' "${NAME}" 2>&1 | grep -i -E "(started vsock forwarder|SSH server does not seem running on vsock port)"; then
 			set +x
 			diagnose "${NAME}"
 			ERROR ".ssh.overVsock=true did not enable vsock forwarder"
@@ -348,7 +348,7 @@ if [[ -n ${CHECKS["ssh-over-vsock"]} ]]; then
 		INFO 'Testing .ssh.overVsock=null configuration'
 		limactl stop "${NAME}"
 		# Detection of the SSH server on VSOCK may fail; however, a failing log indicates that controlling detection via the environment variable works as expected.
-		if ! limactl start --set '.ssh.overVsock=null' "${NAME}" 2>&1 | grep -i -E "(started vsock forwarder|Failed to detect SSH server on vsock)"; then
+		if ! limactl start --set '.ssh.overVsock=null' "${NAME}" 2>&1 | grep -i -E "(started vsock forwarder|SSH server does not seem running on vsock port)"; then
 			set +x
 			diagnose "${NAME}"
 			ERROR ".ssh.overVsock=null did not enable vsock forwarder"

pkg/driver/vz/vm_darwin.go

@@ -116,7 +116,9 @@ func startVM(ctx context.Context, inst *limatype.Instance, sshLocalPort int) (vm
 								logrus.Infof("Detected SSH server is listening on the vsock port; changed %s to proxy for the vsock port", hostAddress)
 								usernetSSHLocalPort = 0 // disable gvisor ssh port forwarding
 							} else {
-								logrus.WithError(err).Warn("Failed to detect SSH server on vsock port, falling back to usernet forwarder")
+								logrus.WithError(err).WithField("hostAddress", hostAddress).
+									Debugf("Failed to start vsock forwarder (systemd is older than v256?)")
+								logrus.Info("SSH server does not seem running on vsock port, using usernet forwarder")
 							}
 						} else {
 							logrus.WithError(err).Warn("Failed to wait for the guest SSH server to become available, falling back to usernet forwarder")

pkg/osutil/osutil_unix.go

@@ -8,6 +8,7 @@ package osutil
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"os/exec"
@@ -36,3 +37,7 @@ func Sysctl(ctx context.Context, name string) (string, error) {
 	}
 	return strings.TrimSuffix(string(stdout), "\n"), nil
 }
+
+func IsEACCES(err error) bool {
+	return errors.Is(err, unix.EACCES)
+}

pkg/osutil/osutil_windows.go

@@ -57,3 +57,7 @@ func SignalName(sig os.Signal) string {
 func Sysctl(_ context.Context, _ string) (string, error) {
 	return "", errors.New("sysctl: unimplemented on Windows")
 }
+
+func IsEACCES(err error) bool {
+	return errors.Is(err, syscall.ERROR_ACCESS_DENIED) || errors.Is(err, syscall.WSAEACCES)
+}

pkg/portfwd/listener.go

@@ -14,6 +14,8 @@ import (
 	"sync"
 
 	"github.com/sirupsen/logrus"
+
+	"github.com/lima-vm/lima/v2/pkg/osutil"
 )
 
 type ClosableListeners struct {
@@ -102,7 +104,7 @@ func (p *ClosableListeners) forwardTCP(ctx context.Context, dialContext func(ctx
 	}
 	tcpLis, err := Listen(ctx, p.listenConfig, hostAddress)
 	if err != nil {
-		logrus.Errorf("failed to listen to TCP connection: %v", err)
+		logListenError(err, "tcp", hostAddress)
 		p.listenersRW.Unlock()
 		return
 	}
@@ -139,7 +141,7 @@ func (p *ClosableListeners) forwardUDP(ctx context.Context, dialContext func(ctx
 
 	udpConn, err := ListenPacket(ctx, p.listenConfig, hostAddress)
 	if err != nil {
-		logrus.Errorf("failed to listen udp: %v", err)
+		logListenError(err, "udp", hostAddress)
 		p.udpListenersRW.Unlock()
 		return
 	}
@@ -162,3 +164,41 @@ func prepareUnixSocket(hostSocket string) error {
 	}
 	return nil
 }
+
+func logListenError(err error, proto, hostAddress string) {
+	var negligibleReason string
+	if proto != "unix" {
+		if _, portStr, err := net.SplitHostPort(hostAddress); err == nil {
+			switch proto {
+			case "tcp":
+				//nolint:gocritic // singleCaseSwitch: should rewrite switch statement to if statement
+				switch portStr {
+				case "53":
+					negligibleReason = "DNS port (often conflicts with the system resolver)"
+				}
+			case "udp":
+				switch portStr {
+				case "53":
+					negligibleReason = "DNS port (often conflicts with the system resolver)"
+				case "323":
+					negligibleReason = "NTP port (often conflicts with the system NTP server)"
+				case "5353":
+					negligibleReason = "mDNS port (often conflicts with the system mDNS responder)"
+				case "5355":
+					negligibleReason = "LLMNR port (often conflicts with the system LLMNR responder)"
+				}
+			}
+		}
+		if osutil.IsEACCES(err) {
+			negligibleReason = "privileged port"
+		}
+	}
+
+	if negligibleReason != "" {
+		logrus.WithError(err).WithField("negligible-reason", negligibleReason).Debugf("failed to listen %s: %s", proto, hostAddress)
+		logrus.Infof("Not forwarding %s %s", strings.ToUpper(proto), hostAddress)
+		return
+	}
+
+	logrus.WithError(err).Warnf("failed to listen %s: %s", proto, hostAddress)
+}

pkg/portfwd/listener_darwin.go

@@ -22,7 +22,7 @@ func Listen(ctx context.Context, listenConfig net.ListenConfig, hostAddress stri
 		var lc net.ListenConfig
 		unixLis, err := lc.Listen(ctx, "unix", hostAddress)
 		if err != nil {
-			logrus.WithError(err).Errorf("failed to listen unix: %v", hostAddress)
+			logListenError(err, "unix", hostAddress)
 			return nil, err
 		}
 		return unixLis, nil
@@ -34,14 +34,15 @@ func Listen(ctx context.Context, listenConfig net.ListenConfig, hostAddress stri
 	if !localIP.Equal(IPv4loopback1) || localPort >= 1024 {
 		tcpLis, err := listenConfig.Listen(ctx, "tcp", hostAddress)
 		if err != nil {
-			logrus.Errorf("failed to listen tcp: %v", err)
+			logListenError(err, "tcp", hostAddress)
 			return nil, err
 		}
 		return tcpLis, nil
 	}
-	tcpLis, err := listenConfig.Listen(ctx, "tcp", fmt.Sprintf("0.0.0.0:%d", localPort))
+	hostAddressPseudo := net.JoinHostPort("0.0.0.0", localPortStr)
+	tcpLis, err := listenConfig.Listen(ctx, "tcp", hostAddressPseudo)
 	if err != nil {
-		logrus.Errorf("failed to listen tcp: %v", err)
+		logListenError(err, "tcp", hostAddressPseudo)
 		return nil, err
 	}
 	return &pseudoLoopbackListener{tcpLis}, nil
@@ -55,14 +56,15 @@ func ListenPacket(ctx context.Context, listenConfig net.ListenConfig, hostAddres
 	if !localIP.Equal(IPv4loopback1) || localPort >= 1024 {
 		udpConn, err := listenConfig.ListenPacket(ctx, "udp", hostAddress)
 		if err != nil {
-			logrus.Errorf("failed to listen udp: %v", err)
+			logListenError(err, "udp", hostAddress)
 			return nil, err
 		}
 		return udpConn, nil
 	}
-	udpConn, err := listenConfig.ListenPacket(ctx, "udp", fmt.Sprintf("0.0.0.0:%d", localPort))
+	hostAddressPseudo := net.JoinHostPort("0.0.0.0", localPortStr)
+	udpConn, err := listenConfig.ListenPacket(ctx, "udp", hostAddressPseudo)
 	if err != nil {
-		logrus.Errorf("failed to listen udp: %v", err)
+		logListenError(err, "udp", hostAddressPseudo)
 		return nil, err
 	}
 	return &pseudoLoopbackPacketConn{udpConn}, nil

pkg/portfwd/listener_others.go

@@ -9,8 +9,6 @@ import (
 	"context"
 	"net"
 	"path/filepath"
-
-	"github.com/sirupsen/logrus"
 )
 
 func Listen(ctx context.Context, listenConfig net.ListenConfig, hostAddress string) (net.Listener, error) {
@@ -22,7 +20,7 @@ func Listen(ctx context.Context, listenConfig net.ListenConfig, hostAddress stri
 		var lc net.ListenConfig
 		unixLis, err := lc.Listen(ctx, "unix", hostAddress)
 		if err != nil {
-			logrus.WithError(err).Errorf("failed to listen unix: %v", hostAddress)
+			logListenError(err, "unix", hostAddress)
 			return nil, err
 		}
 		return unixLis, nil