COMPLETELY Uninstall Docker in Ubuntu [Step-by-Step]

Table of Contents

Uninstalling Docker on Ubuntu

Docker is one of the well-known containerization tools which is widely used in most organizations. Docker helps the developer build, test and deploy their application seamlessly across various environments. It is one of the best offerings and an important tool in the area of DevOps.

In a few cases, you might not be willing to use docker and you may want to uninstall Docker from your system. How do we do that?

In this article, let us understand how to uninstall Docker on Ubuntu OS. Let us get started.

Uninstall Docker Engine

Step-1: Removing Docker Images, Containers, Volumes, and Configurations

Docker utilizes images as blueprints for applications, containers as running instances, volumes for persistent storage, and configurations to customize behaviors.

Remove docker images

docker rmi $(docker images -a -q)

Remove all exited docker containers

docker rm $(docker ps -a -f status=exited -q)

Remove running docker containers by first stopping them and later removing them

docker stop $(docker ps -a -q)
docker rm $(docker ps -a -q)

Remove all docker networks

docker network prune

The docker system prune -a command cleans up unused Docker components, freeing space but also potentially resulting in data loss. Care should be taken before executing cleanup commands to ensure critical data is backed up.

docker system prune -a

The command docker system prune -a is a powerful tool that removes:

All stopped containers
All networks not used by at least one container
All volumes not used by at least one container
All images without at least one container associated with them
All build cache

ALSO READ: Understanding Docker Vs Containerd

Impact of Running this Command:

Frees Up Space: Docker components, especially images and volumes, can take up a significant amount of disk space. Removing them will free up this space.
Loss of Data: Any data stored in stopped containers and unused volumes will be lost. The loss is permanent unless backups exist.
Inability to Start Certain Containers: If an image is deleted and isn't available online, a container based on that image can't be restarted unless the image is repulled or rebuilt.
Network Cleanup: Unused custom networks will be removed, but built-in networks like bridge, host, and none will remain.

Step-2: Delete the Docker packages

You must know the available docker packages before deleting them. Let us list all the available docker packages on our system with the command

$ dpkg -l | grep -i docker

Sample Output

root@host01:~$ dpkg -l | grep -i docker
ii  docker-buildx-plugin                  0.10.4-1~ubuntu.22.04~jammy             amd64        Docker Buildx cli plugin.
ii  docker-ce                             5:24.0.1-1~ubuntu.22.04~jammy           amd64        Docker: the open-source application container engine
ii  docker-ce-cli                         5:24.0.1-1~ubuntu.22.04~jammy           amd64        Docker CLI: the open-source application container engine
ii  docker-ce-rootless-extras             5:24.0.1-1~ubuntu.22.04~jammy           amd64        Rootless support for Docker.
ii  docker-compose                        1.29.2-1                                all          define and run multi-container Docker applications with YAML
ii  docker-compose-plugin                 2.18.1-1~ubuntu.22.04~jammy             amd64        Docker Compose (V2) plugin for the Docker CLI.
ii  python3-docker                        5.0.3-1                                 all          Python 3 wrapper to access docker.io's control socket
ii  python3-dockerpty                     0.4.1-2                                 all          Pseudo-tty handler for docker Python client (Python 3.x)

Upon identifying the docker packages, now go ahead and delete them using the below command

sudo apt-get purge docker-ce docker-ce-cli containerd.io

You will notice that the docker packages will be deleted upon execution of the command.

Output

Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following packages were automatically installed and are no longer required:
  bridge-utils containerd pigz runc systemd-hwe-hwdb ubuntu-fan
Use 'sudo apt autoremove' to remove them.
The following packages will be REMOVED:
  docker.io*
0 upgraded, 0 newly installed, 1 to remove and 104 not upgraded.
After this operation, 158 MB disk space will be freed.
(Reading database ... 208231 files and directories currently installed.)
Removing docker.io (20.10.12-0ubuntu4) ...
'/usr/share/docker.io/contrib/nuke-graph-directory.sh' -> '/var/lib/docker/nuke-graph-directory.sh'
Warning: Stopping docker.service, but it can still be activated by:
  docker.socket
Processing triggers for man-db (2.10.2-1) ...
(Reading database ... 208025 files and directories currently installed.)
Purging configuration files for docker.io (20.10.12-0ubuntu4) ...

Nuking /var/lib/docker ...
  (if this is wrong, press Ctrl+C NOW!)

+ sleep 10

+ rm -rf /var/lib/docker/buildkit /var/lib/docker/containers /var/lib/docker/image /var/lib/docker/network /var/lib/docker/nuke-graph-directory.sh /var/lib/docker/overlay2 /var/lib/docker/plugins /var/lib/docker/runtimes /var/lib/docker/swarm /var/lib/docker/tmp /var/lib/docker/trust /var/lib/docker/volumes
dpkg: warning: while removing docker.io, directory '/etc/docker' not empty so not removed

Uninstalling docker will not delete all the docker stuff. Hence, you must remove the docker images, containers, volumes, and other configurations that you created since they are not removed automatically.

ALSO READ: docker stop all containers [SOLVED]

In this section let us understand how to remove docker images, containers, volumes, and networks.

NOTE:

If you do not want to remove the docker images, containers, volumes, and network that are created one by one, then you can jump to Step-7 discussed in the next section which also does the cleanup.

Step-3: Deleting the remaining docker files

You can execute the commands to completely remove docker and its related files from your system.

All the docker files will be in the /var/lib/docker path so you have to remove the folder.

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

Delete the docker group that you have created in order to run the docker as non-root user or without sudo

sudo groupdel docker

Delete the docker socket using the command below

sudo rm -rf /var/run/docker.sock

In case you have docker-compose installed, delete that using the command below

sudo rm -rf /usr/local/bin/docker-compose
sudo rm -rf /etc/docker
sudo rm -rf ~/.docker

With this, the uninstallation of docker will be successful. You can verify if the docker has been uninstalled by typing $ docker command

Upon successful uninstallation of docker, you will see the below output.

Output

bash: /usr/bin/docker: No such file or directory

This confirms that Docker is no longer available in your system. In case you want to use Docker, you have to re-install it on your system.

Step-4: Removing Docker User Group

Docker often creates a user group named docker. Provide a command to delete it:

sudo groupdel docker

Step-5: Cleaning Up Unused Packages

Recommend running:

sudo apt-get autoremove

This command removes packages that were installed as dependencies and are no longer used.

Summary

The article guides you about how to uninstall docker and also how to delete all the docker images, containers, etc. Hope this article helped you understand the topic. I suggest you try out the steps explained in this article and in case you have any queries or doubts, please feel free to reach out to us and we will respond at the earliest.

ALSO READ: docker logs command [Detailed Tutorial]

Thanks for reading the article. happy learning!!

References

https://docs.docker.com/engine/install/ubuntu/#prerequisites
https://askubuntu.com/questions/935569/how-to-completely-uninstall-docker