Learn how to install Docker on Ubuntu in this easy-to-follow guide for beginners. Just follow the steps and start using Docker in a matter of minutes.
Docker is a software platform that packages the application and all its dependencies in the containers – small and lightweight execution environments that share the operating system’s kernel but otherwise operate in isolation from one another.
They are similar to virtual machines, but containers are more portable and resource-friendly.
This article will show you the easiest way to install Docker on Ubuntu and get it running.
For a detailed introduction to the different components of a Docker container, you can check out our guide: What is a Docker Container: An Introductory Guide for Beginners.
Installing Docker on Ubuntu
Docker is available for installation from the standard Ubuntu repos, but it may not always be the latest version. So to ensure we get the newest version, we’ll install Docker from the official Docker repository.
1. Update Packages
First, update the packages index and install the dependencies necessary to add a new HTTPS repository.
sudo apt update
sudo apt install apt-transport-https ca-certificates curl gnupg software-properties-common
2. Add the Docker Repo
Next, import the GPG key for the official Docker repository to your system. This security feature ensures that the software you’re installing is authentic.
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
To be able to install Docker on your Ubuntu system, you must first add the stable Docker APT repository to it:
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
Finally, update the package database with the Docker packages from the newly added repo:
sudo apt update
3. Install Docker
To install the latest version of Docker on Ubuntu, run the command below.
sudo apt install docker-ce docker-ce-cli containerd.io
Congratulations! Docker should now be installed; the service started and enabled to start on boot.
In addition, you can check the Docker state using:
sudo systemctl is-active docker
When a new version of Docker is released, you can update the packages using the standard apt update
procedure.
Enabling Non-root Users to Run Docker Commands
So far, we have successfully installed a Docker on your Ubuntu system.
Only root and users with sudo privileges can execute Docker commands by default. If you attempt to run the docker
command without prefixing it with sudo
, you’ll get an output like this:
To run Docker commands as a non-root user, you must add your user to the docker group. To do that, type in:
sudo usermod -aG docker ${USER}
In the command shown above, ${USER}
is an environment variable that holds your username. To apply for the new group membership, log out and back in.
Conclusion
We’ve shown you how to install Docker on Ubuntu in this tutorial. To learn more about Docker, check out the official Docker documentation.