10  Change docker location

The standard data directory used for docker is /var/lib/docker on our virtual machine. Since this directory will store a lot of data it can become quite large. Therefore, we move the docker data directory to our volumne mnt/vdb.

Here are the steps to move the directory:

• Stop docker daemon

sudo systemctl stop docker

• Create a new docker directory in /mnt/vdb:

sudo mkdir -p /mnt/vdb/docker

• Make a copy of your current docker directory in the new location:

sudo rsync -a /var/lib/docker/ /mnt/vdb/docker

• Create a backup

sudo mv /var/lib/docker /var/lib/docker-backup

• Create a symbolic link (symlink):

sudo ln -s /mnt/vdb/docker /var/lib/docker

• Start docker:

sudo systemctl start docker

• Check if the docker image “hello-world” is still accessible:

sudo docker ps -a

You can now remove your backup:

sudo rm -rf /var/lib/docker-backup

That’s it!