How to Install and Use Docker on Ubuntu - Tips and Tricks

How to Install and Use Docker on Ubuntu: A Comprehensive Tutorial

An indispensable tool for developers, Docker allows to package and run applications in completely isolated environments called containers. Docker is known for its potential to make applications portable and provide consistent environments, reducing "it works on my machine" issues. Moreover, Docker has the ability to make the deployment of applications more flexible and scalable. This tutorial will guide you on how to install Docker on Ubuntu and offer useful tips and tricks when using it.

Prerequisites

Please ensure you meet the following prerequisites before you proceed:

• You should have Ubuntu 16.04 or later installed and be logged in as a non-root user with sudo privileges.

• You should have access to a terminal/command line.

• You should have apt package handler installed. If not, you can install it using the following command: 'sudo apt-get install apt'

Installing Docker on Ubuntu

Step 1: Update Your System

Firstly, make sure your system is updated with the latest versions of the packages. Run the following commands to update your system:

$ sudo apt-get update
$ sudo apt-get upgrade

Step 2: Install Docker

You can install Docker from the official Ubuntu repositories or directly from Docker's repositories for the latest version. For this guide, we will install Docker from Docker’s repository. Start by adding the GPG key as follows:

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

Once you've added the key, add the Docker repository to your system:

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

You can then update your packages and install Docker using the following commands:

$ sudo apt-get update
$ sudo apt-get install docker-ce

Step 3: Verify the Installation

Upon completion of the installation, you can verify it by checking the Docker version as follows:

$ docker --version

If it displays the Docker version, then you have successfully installed Docker on your Ubuntu system.

Using Docker on Ubuntu

Running a Docker Container

You can run Docker containers using Docker images. Docker Hub, Docker's public registry, hosts thousands of Docker images. As a test, you can run the hello-world image.

$ docker run hello-world

Tips and Tricks

Using Docker with Sudo

Usually, you need to use sudo to run Docker commands on Ubuntu. To avoid this, you can add your user to the docker group. Here’s how:

$ sudo usermod -aG docker ${USER}

Avoiding Docker Cache Issues

Sometimes Docker builds can be slow due to Docker's caching mechanism. Use the '--no-cache' flag to avoid this problem.

Creating Dockerfile

You should take advantage of Dockerfiles, as they enable you to build Docker images effortlessly. This not only improves productivity but also ensures consistency.

In summary, Docker, as a powerful and user-friendly containerization platform, provides numerous benefits for developing, distributing, and running applications. By following our comprehensive guide, you should now be capable of installing Docker on Ubuntu and have learned some useful tips that will come in handy while utilizing Docker.