Wrap up

Housekeeping on your Docker server

'docker ps' shows containers running on your host
'docker stop [ID]' stops the execution of the container with the stated id.
'docker rm [ID]' removes the container matching id (can be a list of ids)
'docker rmi [ID]' removes pulled image id (only do this is space is a concern)
'docker stats ' (i.e. ‘top’ for docker containers)

Have trouble remembering those IDs or want to script them?

cid - $(docker run....)
docker kill $cid
docker rm $cid

Want to stop and remove all currently running containers?

docker stop $(docker ps -aq)
docker rm $(docker ps -aq)

Dockerfile tricks

• Use && to combine command - this reduces the number of layers and can result in smaller images (downside file is not so readable
• Use \ to continue long lines (just like Linux) which can improve readability when you have large lists of pre requisite packages
• If you look at my Dockerfiles you will notice I prefix all apt-get installs with an apt-get to ensure ALL the packages get updated (this can be a downside of the layers) and I try and clear up temp & cache files to reduce the size of a layer which translates into a smaller container.
• Spend some time examining other people's Dockerfiles on the Docker Hub and you will learn lots of tricks (even broken ones have value here).