things-i-have-learned-about-docker.md

Docker

Images

• Remove dangling images

  docker rmi $(docker images -f "dangling=true" -q)

• List current images

  docker image ls

• Remove all unused images

  docker image prune -a

Containers

• Wipe out all

  docker rm $(docker ps -a -q)

Remove all the containers that are not running (exited)

docker rm $(docker ps -q -f status=exited) 

Delete all stopped containers, dangling images, networks, unused volumes and build cache

docker system prune -a --volumes

Tailing logs

docker logs -t --tail 1000 <container_name> 2>&1 | grep -i error

• Running docker stats you’ll know about CPU, memory and network usages and if some container is not performing well you can always stop it

RUN apt-get install -y foo bar && \
    # use the packages downloaded
    ... &&\
    rm -rf /var/lib/apt/lists/*