Docker - update data-root

Support
1

Hi guys,

I need to move all data (container, volume ecc) of docker in a new raid5 partition.

I have followed this steps that was working fine in other system.

sudo service docker stop

Add a configuration file to tell the docker daemon what is the location of the data directory
creating new file daemon.json under the directory /etc/docker:
{ 
   "data-root": "/path/to/your/docker" 
}

sudo rsync -aP /var/lib/docker/ /path/to/your/new/docker

sudo mv /var/lib/docker /var/lib/docker.bkp

signal-event nethserver-docker-update

at this point I should find all the old containers already “ready”, but I can’t find it any of those… only the portainer is present.

And the docker info show me the docker root dir not changed.

# docker info | grep Root
 Docker Root Dir: /var/lib/docker

In the documentation there aren’t something that can help… can you suggest what i am missing?
Thanks

Update- One bit more.

Also change the docker.service the data-root doesn’t change.

nano /lib/systemd/system/docker.service
ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock --data-root /fabristorage
signal-event nethserver-docker-update
2

why not change the name of the current directory and mount the RAID5 into the same “old directory name”?

1 Like
3

The symlink way works. Mounting the RAID5 to /var/lib/docker as @pike suggested should work too.

See this thread for more information about the symlink method.

4

Thanks for suggestion.

Symlink works fine!

just some basic recap, hope that can help to someone

stop all container
sudo service docker stop
sudo rsync -aP /var/lib/docker/ /raid5example/docker
rm -fr /var/lib/docker
ln -s /raid5example/docker/ /var/lib
signal-event nethserver-docker-update

And the portainer is perfectly in sync.

1 Like
5

Thanks for this experience, @fabgatw