Change Docker Root directory

I want to change the default directory in docker..

The default directory of docker is (/var/lib/docker) and since this directory contains all the images , volumes etc,to get the basic information about your Docker configuration, execute:

 $ docker info

The out put will be as which contains  information about the storage driver and the  docker root directory.
 Storage Driver: overlay2
 Docker Root Dir: /var/lib/docker

This dictory can become quite large in a very short period. With the recent versions of docker, you can set the value of the data-root parameter to any custom path of your choice, however being humans, some of us doesn’t likes changes and we keep the default ones.. :) Eventually this directory is gonna grow , offcourse not if you are not gonna do anything after bringing up the friendly hello-world docker container.

Firstly, Stop the docker daemon..

If you are running docker as root, you need to prefix sudo with the command, otherwise not.

sudo systemctl docker status

or

sudo service docker status

What next ??

Next, we need to edit the service startup script to include our changes. The location of the service startup script can be found by running:

sudo systemctl docker status

The output of the command would be like :

Edit the file (/lib/systemd/system/docker.service) in your text editor.

Add -g (/path/to/docker/) at the end of ExecStart directive. The complete line should look like this.

ExecStart=/usr/bin/dockerd -g *(/path/to/docker/)*

Execute the below command

sudo systemctl daemon-reload sudo systemctl restart docker

Execute the command to check the new docker directory

docker info | grep "loop file\|Dir"

Summary

Docker is an important part of many people’s environments and tooling. Sometimes, Docker feels a bit like magic by solving issues in a very smart way without telling the user how things are done behind the scenes. Still, Docker is a regular tool that stores its heavy parts in locations that can be opened and changed.