Explainer
Fix permission denied on the Docker daemon socket
Verify the socket and account, grant appropriate group access, and repair user configuration ownership only when that is the failing path.
Explainer
Resolve a Docker container name conflict
Find the existing container, decide whether to restart, retain, or remove it, and avoid destructive cleanup hidden in deployment scripts.
Explainer
Recover from Docker “no space left on device”
Locate the exhausted filesystem or quota, remove reviewed resources, and prevent log growth without editing Docker-managed log files.
Explainer
Investigate a Docker permission denial by the failing path
Distinguish daemon access, stale service credentials, client configuration, container UID/GID mapping, and SELinux policy.
Explainer
Find a host address from inside a Docker container
Resolve a supported host name or inspect the network gateway without assuming every gateway is the physical host.
Explainer
Choose a shell or inspection method for a Docker container
Use exec for a running container, Compose exec for a service, and offline inspection when the container is stopped or has no shell.
Explainer
Wait for a dependency to become healthy in Docker Compose
Use health-based startup conditions, validate the probe itself, and keep application retries for failures after startup.
Explainer
Manage persistent data in Docker
Choose volumes or bind mounts, back up databases consistently, restore into a fresh volume, and review cleanup scope.
Explainer
Pass environment variables to Docker containers
Use run flags, environment files, or Compose settings while distinguishing interpolation, process scope, and secret handling.
Explainer
Connect Docker containers by name
Use a user-defined network for service discovery, then test the actual application protocol rather than relying on ping.
Explainer
Keep Docker data after a container stops or is removed
Understand writable layers, rescue files from stopped containers, and choose persistent mounts with tested backups.
Explainer
Push an image to a private Docker registry
Authenticate, tag the intended destination, push and verify the digest, and troubleshoot registry trust and authorization.