Docker MCP Server

Permission denied connecting to Docker daemon socket

Add your user to docker group: sudo usermod -a -G docker $USER, then log out and back in. Alternatively, run sudo systemctl start docker to ensure daemon is running.

Cannot connect to Docker daemon - connection refused

Start Docker daemon: sudo systemctl start docker (Linux) or launch Docker Desktop (Mac/Windows). Verify daemon is running: docker ps. Check DOCKER_HOST environment variable points to correct socket.

Error: /var/run/docker.sock has wrong permissions

Run sudo chmod 666 /var/run/docker.sock (temporary fix) or add user to docker group (permanent). Verify socket file exists: ls -l /var/run/docker.sock.

Docker API version mismatch error

Set DOCKER_API_VERSION environment variable to match your Docker version. Run docker version to check API version. Update MCP server config with correct API version (e.g., 1.43).

Container operations fail with authentication errors

Run docker login to authenticate with registry. Verify registry credentials are correct. For private registries, ensure network access and check firewall rules don't block Docker registry ports.