As anyone who works with docker knows, images and containers accumulate rapidly.

All containers can be cleared down with

docker rm $(docker ps -a -q)

And likewise, all Images with

docker rmi -f $(docker images -q)

What I wasn’t aware of was the dangling volume issue. While I had no images or containers left after the above, I did however have 20Gb taken up in dangling volumes which I was oblivious to until I wondered where all my system space had disappeared to.

You can check for dangling volumes independent of containers with

docker volume ls -f dangling=true

And remove them with

docker volume rm $(docker volume ls -qf dangling=true)

Or you can remove them with the associated container by adding the –v flag (e.g. docker rm –v container name) if you remember to put the flag on every time. I would suggest incorporating these to your team purge scripts/procedures for a better cleanup.

More information can be found here (recommended reading)

  • http://serverfault.com/questions/683910/removing-docker-data-volumes
  • http://container42.com/2014/11/03/docker-indepth-volumes/