change mount point for docker containers

mountdocker.md

I want docker to stop using my root partition for storing docker containers, and use a different partition instead, e.g. /home

These steps worked for me:

1. Stop all containers sudo docker stop $(docker ps -a -q)
2. Stop docker sudo service docker stop
3. Copy docker directory cp -r /var/lib/docker/* /home/docker/
4. Unmount all old docker overlays umount -f /var/lib/docker/overlay/ and umount -f /var/lib/docker/containers/*/mounts/shm
5. Add or update /etc/docker/daemon.json with

{
  "graph": "/home/docker/"
  }

6. Start docker with sudo service docker start
7. Remove old /var/lib/docker/

update: graph is outdated, use data-root

{
  "data-root": "/new/path/to/docker-data"
}

and then

sudo systemctl daemon-reload
sudo systemctl restart docker

references

• https://stackoverflow.com/a/50217666/5819113
• https://blog.adriel.co.nz/2018/01/25/change-docker-data-directory-in-debian-jessie/