In this post i am going to show you how to find the Docker Root Directory and how to change the location so that docker can save the files in some other location (For Backup or High Availability).
This is the commands to find and verify the Docker Root Folder.
root@master:~# docker info | grep -i root Docker Root Dir: /var/lib/docker root@master:~# sudo du -sh /var/lib/docker/ 2.7G /var/lib/docker/ root@master:~# cd /var/lib/docker/ root@master:/var/lib/docker# ll total 56 drwx--x--x 14 root root 4096 Nov 16 11:31 ./ drwxr-xr-x 40 root root 4096 Nov 16 07:53 ../ drwx------ 2 root root 4096 Nov 16 07:53 builder/ drwx--x--x 4 root root 4096 Nov 16 07:53 buildkit/ drwx------ 2 root root 4096 Nov 17 12:58 containers/ drwx------ 3 root root 4096 Nov 16 07:53 image/ drwxr-x--- 3 root root 4096 Nov 16 07:53 network/ drwx------ 46 root root 4096 Nov 17 12:58 overlay2/ drwx------ 4 root root 4096 Nov 16 07:53 plugins/ drwx------ 2 root root 4096 Nov 16 11:31 runtimes/ drwx------ 2 root root 4096 Nov 16 07:53 swarm/ drwx------ 2 root root 4096 Nov 17 12:42 tmp/ drwx------ 2 root root 4096 Nov 16 07:53 trust/ drwx------ 13 root root 4096 Nov 16 13:41 volumes/
To change the location of the Root Directory
- Stop all containers
- Stop the Docker servicer
sudo systemctl stop docker
After all the above was done.We need to enter to the docker config file.
sudo vi /lib/systemd/system/docker.service

Now we need to move the docker folder form his old location to the new one.
root@master:/var/lib/docker# sudo rm -rf /mnt/docker root@master:/var/lib/docker# ls /mnt/ root@master:/var/lib/docker# mv docker /mnt/
After we moved the folder we need to start the service again.
sudo systemctl restart docker
That’s it you ready to keep using Docker 🙂