Stop docker
sudo systemctl stop docker
nano /etc/docker/daemon.json
Add data
{
"data-root": "/new/path/to/docker-data"
}
Check docker has been stopped
ps aux | grep -i docker | grep -v grep
Copy the files to the new location
sudo rsync -axPS /var/lib/docker/ /new/path/to/docker-data
Options explanation, check out the man page for more info
-a, --archive archive mode; equals -rlptgoD (no -H,-A,-X) -x, --one-file-system don't cross filesystem boundaries -P show progress during transfer -S, --sparse handle sparse files efficiently
Start Docker back up
sudo systemctl start docker
Check Docker has started up using the new location
docker info | grep ‘Docker Root Dir’
Check everything has started up that should be running
docker ps
Leave both copies on the server for a few days to make sure no issues arise, then feel free to delete it.
sudo rm -r /var/lib/docker