Guide for Installing and Configuring Docker on Linux

Guide for Installing and Configuring Docker on Linux. Installing and configuring Docker on Linux is a simple process if you follow the correct steps. Once configured, Docker provides a secure, fast and efficient environment for development and running applications. It is an essential tool for system administrators, developers and DevOps teams.

Guide for installation and configuration

Docker is an open-source platform that allows running applications in isolated containers, easy to manage and portable. This guide will teach you how to install and configure Docker on a Linux system, step by step, to benefit from the advantages of modern containerization.

Prerequisites

Make sure you have:

• An updated Linux system (Ubuntu, Debian, CentOS, etc.);
• Root access or sudo privileges;
• Internet connection.

Guide for Installing and Configuring Docker

1. System update

Start by updating the packages:

sudo apt update && sudo apt upgrade -y

2. Installing Docker on Ubuntu/Debian

2.1 Installing required packages

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

2.2 Adding Docker's 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

2.3 Adding the official Docker 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

2.4 Installing Docker Engine

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

3. Verifying the installation

To verify if Docker is installed correctly:

sudo docker --version

Running a test container:

sudo docker run hello-world

4. Adding user to docker group

To use Docker without sudo:

sudo usermod -aG docker $USER
newgrp docker

5. Enabling and starting Docker service

sudo systemctl enable docker
sudo systemctl start docker

6. Configuring Docker

The configuration file is located at:

/etc/docker/daemon.json

Configuration example with logging and custom network:

{
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "10m",
    "max-file": "3"
  },
  "storage-driver": "overlay2"
}

Apply the changes:

sudo systemctl restart docker

7. Installing Docker Compose (if not included)

For some older distributions:

sudo curl -L "https://github.com/docker/compose/releases/latest/download/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
sudo chmod +x /usr/local/bin/docker-compose
docker-compose --version

8. Quick test with an nginx container

Run a simple web server:

docker run -d -p 8080:80 --name nginx-server nginx

Then access http://localhost:8080 in your browser.

9. Useful Docker commands

• docker ps: displays active containers
• docker stop ID: stops a container
• docker rm ID: deletes a container
• docker images: lists downloaded images
• docker exec -it ID bash: accesses an active container

10. Uninstalling Docker (optional)

To completely remove Docker from the system:

sudo apt purge docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
sudo rm -rf /var/lib/docker /etc/docker
sudo rm /etc/apt/sources.list.d/docker.list