juicedata/juicefs · error

listen: %s

Error message

listen: %s

What it means

After computing the listen address, startManager calls net.Listen("tcp", addr). This error wraps a listener creation failure, meaning the manager could not bind the TCP port — typically because the port is already in use, the address is not assignable to any interface, or permission is denied for privileged ports.

Source

Thrown at pkg/sync/cluster.go:348

			}
			addr = ip + addr
		}
	} else {
		ip, err := utils.GetLocalIp(net.JoinHostPort(u.Host, "22"))
		if err != nil {
			return "", fmt.Errorf("not found local ip: %s", err)
		}
		logger.Debugf("Use local ip %s", ip)
		addr = ip
	}

	if !strings.Contains(addr, ":") {
		addr += ":"
	}

	l, err := net.Listen("tcp", addr)
	if err != nil {
		return "", fmt.Errorf("listen: %s", err)
	}
	logger.Infof("Listen at %s", l.Addr())
	go func() { _ = http.Serve(l, mux) }()
	return l.Addr().String(), nil
}

func findSelfPath() (string, error) {
	program := os.Args[0]
	if strings.Contains(program, "/") {
		path, err := filepath.Abs(program)
		if err != nil {
			return "", fmt.Errorf("resolve path %s: %s", program, err)
		}
		return path, nil
	}
	for _, searchPath := range strings.Split(os.Getenv("PATH"), ":") {
		if searchPath != "" {
			p := filepath.Join(searchPath, program)

View on GitHub (pinned to c9a67b23e8)

Solutions

1. Free the port: find and stop the process holding it (ss -ltnp / lsof -i :PORT) or pick a different --manager-addr port
2. Use a port >1024 or run with appropriate privileges if binding a privileged port
3. Make sure the IP in --manager-addr exists on the manager host (use 0.0.0.0 or the correct interface IP)

Example fix

// before
--manager-addr 10.0.0.5:8080   # port taken
// after
--manager-addr 10.0.0.5:18080

// Check port availability before starting the manager
if l, err := net.Listen("tcp", addr); err != nil {
	return fmt.Errorf("port %s unavailable: %w", addr, err)
} else {
	l.Close()
}

When it happens

Trigger: startManager binds the resolved addr and net.Listen fails: another process holds the port (address already in use), binding to an IP not present on the host, using a privileged port (<1024) as non-root, or port range exhausted.

Common situations: Previous sync manager still running and holding the port; --manager-addr pointing to the wrong host IP; using port 80/443 without root; docker/k8s port conflicts.

Related errors

• are you connected to the network?
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• failed to convert %s to %s: %w
• (cancelled) upload block %s: %s (after %d tries)

AI-assisted analysis of juicedata/juicefs@c9a67b23e8 (2026-09-06). Data as JSON: /api/errors/04e5f02e56b9f653. Report an issue: GitHub.