Ports are not available: exposing port TCP 0.0.0.0:8080: bind: address already i

Not specified by the original author.

TL;DR: The host port is taken. Identify the holder with docker ps and ss -tlnp, then either stop it or publish a different host port. This message is the newer daemon wording for the classic port conflict; the fix is identical to the older 'port is already allocated' error.

The error

Ports are not available: exposing port TCP the all-interfaces address:8080 -> the all-interfaces address:0: listen tcp4 the all-interfaces address:8080: bind: address already in use

Fix it

1. Check running containers first: docker ps --filter "publish=8080" Expected: the conflicting container, if any.

2. Then host processes: sudo ss -tlnp | grep ':8080' Expected: process and PID.

3. Resolve by stopping the holder or remapping: docker run -p 8081:8080 [image] Expected: starts cleanly.

When this applies

• docker run -p failing with "Ports are not available"
• Docker Desktop and Engine 24+ which use this wording

When this does NOT apply

• Container app failing to bind its OWN port (that is inside the container; check the app config)
• "port is already allocated" (older wording, same fix)

Versions

Docker Engine 23+, Docker Desktop 4.20+.

Why it happens

The daemon pre-validates port availability before creating the container's network endpoint. Anything in the host network namespace already bound to that port, including a previous instance of the same container, trips the check.

Edge cases

• Docker Desktop on Mac/Windows: the "host" here is the Linux VM; a process inside the VM (rare) or the port-forwarding layer can be the holder.
• Ephemeral port exhaustion on busy hosts can produce this for high port numbers; check cat /proc/sys/net/ipv4/ip_local_port_range.
• Restart policies can recreate the conflict automatically; docker update --restart=no the old container before remapping.

Asked: how to fix Ports are not available: exposing port TCP the all-interfaces address:8080: bind: address already in use. Verified answer: Fixes 'Ports are not available' when docker cannot expose a host port. Use when the daemon reports a port as unavailable at container start, typically a conflict with another container or host service. The fix steps above were cross-checked against the accepted community answer at https://stackoverflow.com/questions/73680738/docker-ports-are-not-available-exposing-port-tcp-0-0-0-05432-0-0-0-00 (so:73680738), which confirms the same resolution.

Not specified by the original author.

TL;DR: Another process is listening on the host port you asked for. Run ss -tlnp | grep [port] to find it, kill or stop it, then start the container again. The userland proxy is the daemon component that forwards host ports into containers, and it fails at bind time when the port is taken.

The error

driver failed programming external connectivity on endpoint web: Error starting userland proxy: listen tcp4 the all-interfaces address:80: bind: address already in use

Fix it

1. Find the port from the error message (80 in the example).

2. Find the holder: sudo ss -tlnp | grep ':80 ' Expected: a process name and PID. Common culprits: apache2, nginx, another docker-proxy, Skype on Windows.

3. Stop it or choose a free port: docker run -p 8080:80 [image] Expected: container starts.

4. If the holder is a stale docker-proxy from a crashed container, restart the docker service to clear it.

When this applies

• Published ports failing with the userland proxy message
• Port 80/443 conflicts with a host web server

When this does NOT apply

• "Bind for the all-interfaces address:X failed: port is already allocated" (earlier check, same fix though)
• No ports published (then this error cannot occur; look elsewhere)

Versions

All Docker versions on Linux. Docker Desktop routes through the VM but surfaces the same message.

Why it happens

With the default iptables setup, docker-proxy (the userland proxy) binds the host port to forward traffic into the container's network namespace. The bind is exclusive; a host nginx on port 80 wins the race and the container fails to start.

Edge cases

• Disabling the userland proxy ("userland-proxy": false in daemon.json) changes the plumbing to pure iptables and avoids docker-proxy conflicts, but hairpin NAT behavior changes.
• On systems with both IPv4 and IPv6, the proxy binds both; a holder on only one family still blocks the dual bind.
• docker run -p the loopback address:80:80 binds loopback only and can succeed while the all-interfaces bind fails; useful when the conflict is on the external interface.

Asked: how to fix Error starting userland proxy: listen tcp4 the all-interfaces address:80: bind: address already in use. Verified answer: Fixes the userland proxy 'address already in use' error when starting a container with published ports. Use when the daemon cannot bind the host port because another process holds it. The fix steps above were cross-checked against the accepted community answer at https://github.com/docker/compose/issues/3277 (gh:docker/compose#3277), which confirms the same resolution.

Not specified by the original author.

TL;DR: Something already owns that host port. Find it with docker ps (another container) or ss -tlnp | grep 8080 (a host process), then stop the other container or pick a different host port like -p 8081:8080. Only one listener per host port is allowed, and Docker will not share.

The error

Bind for the all-interfaces address:8080 failed: port is already allocated

Fix it

1. Check for another container on that port: docker ps --format '{{.Names}} {{.Ports}}' | grep 8080 Expected: either a container name (stop or remove it) or nothing.

2. Check host processes: ss -tlnp | grep ':8080' Expected: the process name and PID holding the port.

3. Either free the port (docker stop [name], or stop the host service) or remap: docker run -p 8081:8080 [image] Expected: container starts, reachable on host port 8081.

When this applies

• docker run -p / --publish failing with this exact message
• Restarting a container while the old one still holds the port

When this does NOT apply

• "Ports are not available" (different message, same family; usually the same fix)
• Container-to-container communication (use the container port and docker networks, no host binding needed)

Versions

All Docker versions, all platforms.

Why it happens

-p 8080:8080 asks the daemon to listen on the host's port 8080 for all interfaces. If anything already listens there, the bind syscall fails and the daemon reports it before the container starts.

Edge cases

• A stopped-but-not-removed container does NOT hold the port; only running ones do. docker ps -a showing it is a red herring.
• On Docker Desktop for Mac, host services on the Mac can hold the port; the container port mapping still goes through the VM.
• TIME_WAIT sockets from a just-stopped process can briefly block rebinding; waiting a minute or setting reuse options fixes it.

Asked: how to fix Bind for the all-interfaces address:8080 failed: port is already allocated. Verified answer: Fixes 'port is already allocated' when docker run -p fails because the host port is taken. Use when binding a host port and something (another container or host process) already holds it. The fix steps above were cross-checked against the accepted community answer at https://stackoverflow.com/questions/46176584/docker-bind-for-0-0-0-04000-failed-port-is-already-allocated (so:46176584), which confirms the same resolution.