How to Install Docker on Ubuntu

Step 1: Update the System

Run the following commands to update your system’s package index and install required prerequisites:

sudo apt-get update
sudo apt-get install -y ca-certificates curl gnupg lsb-release

Step 2: Add Docker’s Official GPG Key

Add Docker’s GPG key to ensure the software is authentic:

sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg

Step 3: Add Docker’s Official Repository

Add Docker’s repository to your package manager:

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

Step 4: Install Docker Engine

Update your package index again and install Docker Engine, CLI, and containerd:

sudo apt-get update
sudo apt-get install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

Step 5: Verify the Installation

Run the following command to ensure Docker is installed correctly:

sudo docker --version

You should see the Docker version output.

Step 6: (Optional) Run Docker as a Non-root User

To run Docker without using sudo, add your user to the docker group:

1. Add the current user to the docker group:

   sudo usermod -aG docker $USER
   

2. Log out and back in, or run:

   newgrp docker
   

3. Verify:

   docker run hello-world
   

Step 7: Test Docker

Test Docker by running the following command:

docker run hello-world

This will download a test image and run it in a container.

If you encounter issues during installation, let me know!