How To Install Docker on Ubuntu 20.04 LTS

In this tutorial, we will show you how to install Docker on Ubuntu 20.04 LTS. For those of you who didn’t know, Docker is an open-source project that automates the deployment of applications inside the software container. The container allows the developer to package up all project resources such as libraries, dependencies, assets, etc.

This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo‘ to the commands to get root privileges. I will show you the step-by-step installation of the Docker container on Ubuntu 20.04 Focal Fossa. You can follow the same instructions for Ubuntu 21.04, 18.04, 16.04, and any other Debian-based distribution like Linux Mint.

Prerequisites

• A server running one of the following operating systems: Ubuntu 20.04, 18.04, 16.04, and any other Debian-based distribution like Linux Mint.
• It’s recommended that you use a fresh OS install to prevent any potential issues.
• SSH access to the server (or just open Terminal if you’re on a desktop).
• A non-root sudo useror access to the root user. We recommend acting as a non-root sudo user, however, as you can harm your system if you’re not careful when acting as the root.

Install Docker on Ubuntu 20.04 LTS Focal Fossa

Step 1. First, make sure that all your system packages are up-to-date by running the following apt commands in the terminal.

sudo apt update
sudo apt upgrade
sudo apt install apt-transport-https ca-certificates curl gnupg-agent software-properties-common

Step 2. Installing Docker on Ubuntu 20.04.

It’s recommended to uninstall any old Docker software before proceeding:

sudo apt remove docker docker-engine docker.io

Now we enable the Docker repository, import the repository GPG key, and install the package:

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

Next, add the Docker APT repository to your system:

sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"

Once, that’s imported, update apt again and install it:

sudo apt update
sudo apt install docker-ce docker-ce-cli containerd.io

To install a specific version, first list all the available versions in the Docker repository:

apt list -a docker-ce

Check for the Docker version:

$ docker --version
Docker version 18.03.0-ce, build 0330e24

To check whether docker is running or not, type the following command:

systemctl status docker

To verify that Docker has been successfully installed and that you can execute the docker command without prepending sudo, we’ll run a test container:

docker container run hello-world

The command will download the test image, if not found locally, run it in a container, print a “Hello from Docker” message, and exit.

Congratulations! You have successfully installed Docker. Thanks for using this tutorial for installing the Docker container on Ubuntu 20.04 LTS  (Focal Fossa) system. For additional help or useful information, we recommend you check the official Docker website.