Cli

Need to grab a log file out of a container? Push a quick config change for a one-off test? Don’t redeploy with a bind mount, just use docker compose cp. Basic usage The syntax mirrors docker cp but resolves service names instead of container IDs: # Copy from container to host docker compose cp <service>:<container-path> <host-path> # Copy from host to container docker compose cp <host-path> <service>:<container-path> The direction is determined by which side has the service: prefix. ...

Know the difference between exec and run! Each has its place in your debugging toolkit. The key difference exec: Runs commands in an existing container run: Creates a new container # Exec: enters running container docker compose exec web bash # Run: starts new container docker compose run web bash When to use exec Use exec for debugging running services: # Debug a running web server docker compose exec web bash # Check logs inside container docker compose exec web tail -f /var/log/app.log # Run database queries docker compose exec db psql -U postgres # Check process list docker compose exec web ps aux # Test connectivity from inside docker compose exec web curl http://api:3000/health Important: Container must be running! ...