Introduction
If you are new to Docker, it is a powerful containerization platform that streamlines application development and deployment. Docker enables developers to build, test, and deploy applications in an isolated environment called a container, which is an efficient alternative to a traditional virtual machine. In short, it is a tool that enables developers and system admins to get an application up and running quickly regardless of the OS on which the application runs.
If you are interested in running various applications with different dependencies, or you want to deploy web applications or services in a fast and efficient way without worrying about the underlying environment, you should consider installing Docker on your Ubuntu system. In this guide, we will provide you with a comprehensive step-by-step tutorial on how to install Docker on Ubuntu using various methods.
Step-by-Step Guide with Terminal Commands
Before we begin, it is important to understand that Docker needs a 64-bit architecture in your system. Make sure that your Ubuntu distribution is up-to-date and has a 64-bit architecture. Open the terminal using the keyboard shortcut Ctrl+Alt+T. Follow the instructions below to install Docker on your Ubuntu system.
Download Prerequisite Packages
The first step is to download the prerequisite packages needed for Docker installation. Use the command below to download them:
sudo apt-get update
sudo apt-get install apt-transport-https ca-certificates curl gnupg-agent software-properties-common
Add Docker’s GPG Key
Next, you need to add Docker’s GPG key. Run the following command to do so:
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
Add Docker Repository
Add Docker’s repository with the command below:
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
Install Docker
Update your repository cache by running the command below:
sudo apt-get update
Finally, run the following command to install Docker:
sudo apt-get install docker-ce docker-ce-cli containerd.io
Verify Docker Installation
You can confirm that Docker is installed by running the following command:
sudo docker run hello-world
This command downloads a test image and launches a container, then displays information about the container in the terminal.
Additional Information and Troubleshooting Tips
If you have an issue with the installation, first re-check the installation steps, then check if there is anything wrong with your system dependencies. You can troubleshoot the issue by running the below command:
sudo journalctl -u docker.service
From the output, you will be able to see the error message and diagnose the problem. Refer to the official Docker documentation https://docs.docker.com/engine/install/ubuntu/ for more information about how to install and configure Docker for other versions of Ubuntu.
Graphical Installation with a Package Manager
Alternatively, you can use a graphical interface for Docker installation. The following are methods through package managers:
Introduction to Package Managers
Package Managers are software applications that enable you to search, download, install and delete software packages. These are useful when you have several applications to install and want a more efficient way of handling those installations instead of manually typing in multiple instructions.
Synaptic Package Manager Installation
Synaptic Package Manager is a graphical frontend for apt package manager. You can use it to install Docker by following these steps:
Download Synaptic Package Manager
Install Synaptic Package Manager by running the following command:
sudo apt-get install synaptic
Search and Install Docker
Open the Synaptic Package Manager application and do the following:
- Select “Settings” from the top menu.
- Select “Repositories” and click on “Other Software”.
- Click on “Add”.
- Enter the following command: “deb https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable”.
- Click on “OK” and then click on “Reload”.
- Search for “Docker” in the search bar and then select “Docker.io”.
- Click on the “Apply” button to install Docker.
Ubuntu Software Center Installation
Open Ubuntu Software Center
You can open the Ubuntu Software Center in Ubuntu 20.4 LTS from the Terminal with this command:
software-center
Search and Install Docker
Alternatively, you can navigate to the search bar and type in “docker”. Click on the Docker package that appears in the search result, then click on the “Install” button.
Gnome Software Installation
Open Gnome Software
You can open the Gnome Software application in Ubuntu 20.4 LTS from the Terminal with this command:
gnome-software
Search and Install Docker
Alternatively, you can navigate to the search bar and type in “docker”. Click on the Docker package that appears in the search result, then click on the “Install” button.
Using Snap
Snap is a containerization platform that works like Docker. However, Snap is focused on sandboxed environments that are combined with package management. Here is how to install Docker using Snap:
Introduction to Snap
Snap is a universal packaging system for Linux. It is a containerization/sandbox method based on the Ubuntu snapcraft technology that enables you to use secure and portable applications across multiple Linux distributions. Snap packages are standalone, self-contained applications that include all the dependencies required to run the application. These packages are also updated automatically without requiring any human intervention. And this method of installation ensures that all available Docker installations are securely isolated from each other.
Installing Docker with Snap
Install Snap
Use the following command to ensure Snap is installed:
sudo apt-get install snapd
Install Docker using Snap
Then run the following command to install Docker:
sudo snap install docker
Verify Docker Installation
You can confirm that Docker is installed by running the following command:
sudo docker run hello-world
This command downloads a test image and launches a container, then displays information about the container in the terminal.
Video Tutorial
To make the Docker installation experience more interesting and easier, we have created a video tutorial. Watch the video and follow along to complete the Docker installation process without any hassle. The video covers all installation methods explained in this guide.
Introduction to the Video Tutorial
The video tutorial provides a step-by-step guide to installing Docker on Ubuntu using different methods.
Walkthrough of Docker Installation on Ubuntu
The video presents all the installation methods illustrated in this guide.
Additional Information and Troubleshooting Tips
You will also find some additional tips for troubleshooting Docker installations.
Using a Virtual Machine
If you don’t want to install Docker directly on your Ubuntu system, you can install it on a virtual machine instead. Here’s how:
Introduction to Using a Virtual Machine
A Virtual Machine (VM) is a software environment that emulates a physical computing system with its own hardware and software environment. Using a VM, you can run any OS inside the VM regardless of your computer’s underlying OS. This method gives you complete control over the installation and configuration of Docker without affecting the host operating system.
Setting up VirtualBox
Download and Install VirtualBox
First, download and install Oracle VirtualBox from the official VirtualBox Downloads page.
Create a New Virtual Machine
After the installation of VirtualBox is complete, launch it from your computer. Click on the “New” icon to create a new Virtual Machine. Follow the steps provided by VirtualBox to create a new VM, choosing Ubuntu 18.04 LTS as the OS, and allocating RAM, disk space and Processor as required by your system specification.
Installing Docker on the Virtual Machine
Download Prerequisite Packages
Run the following command below to download prerequisite packages:
sudo apt-get update
sudo apt-get install apt-transport-https ca-certificates curl gnupg-agent software-properties-common
Add Docker’s GPG Key
Next, you need to add Docker’s GPG key. Run the following command to do so:
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
Add Docker Repository
Add Docker’s repository with the command below:
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
Install Docker
Update your repository cache by running the command below:
sudo apt-get update
Finally, run the following command to install Docker:
sudo apt-get install docker-ce docker-ce-cli containerd.io
Verify Docker Installation
You can confirm that Docker is installed by running the following command:
sudo docker run hello-world
This command downloads a test image and launches a container, then displays information about the container in the terminal.
Using Docker with a Script
You can also install Docker on Ubuntu using a script. Scripts are beneficial when you have a requirement of running parallel installations with no user interaction. Here is how:
Introduction to Using a Script for Docker Installation
A shell script is a computer program designed to be run by the Unix/Linux shell, a command-line interpreter. Scripts are suggested if you require installing Docker with a custom specification such as Directories, Volumes, settings of the Docker daemon, and automated installation without user interaction.
Providing a Script for Docker Installation
Here is an example script to install Docker:
#!/bin/bash
# Download prerequisite packages
sudo apt-get update
sudo apt-get install -y \
apt-transport-https \
ca-certificates \
curl \
gnupg-agent \
software-properties-common
# Add Docker's PGP key
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
# Add Docker repository
sudo add-apt-repository \
"deb [arch=amd64] https://download.docker.com/linux/ubuntu \
$(lsb_release -cs) \
stable"
# Install Docker
sudo apt-get update
sudo apt-get install -y docker-ce docker-ce-cli containerd.io
You can save this script to a file called “docker-install.sh
” and execute it with the ./docker-install.sh
command. Make sure that the file has execute permission. You can set the permissions by running the following command:
chmod +x docker-install.sh
Explanation of Saving and Executing the Script
First, create a new text file and copy the script content to the file. Next, save the script with any name that helps you reference its action.