9  Docker set up

In this tutorial, we cover how to install Docker Engine on Ubuntu. We simply follow the installation steps outlined in the official Docker documentation

9.1 Set up Docker repository

Before you install Docker Engine for the first time on a new host machine, you need to set up the Docker repository. Afterward, you can install and update Docker from the repository.

  • Update the apt package index:
sudo apt-get update
  • Install packages to allow apt to use a repository over HTTPS:
sudo apt-get install \
    ca-certificates \
    curl \
    gnupg \
    lsb-release

  • Confirm the installation with Y

  • Add Docker’s official GPG key:

sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
  • Use the following command to set up the repository:
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \
  $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

9.2 Install Docker Engine

  • Again, update the apt package index:
sudo apt-get update
  • Install Docker Engine, containerd, and Docker Compose:
sudo apt-get install docker-ce docker-ce-cli containerd.io docker-compose-plugin

  • Press Y to continue

  • Verify that the Docker Engine installation is successful by running the hello-world image:

sudo docker run hello-world

This command downloads a test image and runs it in a container. When the container runs, it prints a confirmation message and exits.

Great! You have now successfully installed and started Docker Engine.