Installing Docker

Step-by-step guide to installing Docker on various operating systems.

By Kevin McAleer,    4 Minutes

Installing Docker on Your Machine

This lesson guides you through the installation process of Docker on different operating systems including Windows, MacOS, and Linux.

Prerequisites

Before installing Docker, ensure your system meets the necessary requirements for the Docker edition you’re installing. Generally, you need:

• A 64-bit processor with Second Level Address Translation (SLAT)
• 4GB system RAM
• BIOS-level hardware virtualization support must be enabled in the BIOS settings. For Windows, Hyper-V and Containers Windows features must be enabled.

Installing Docker on Windows

To install Docker on Windows, follow these steps:

1. System Requirements:
   • Windows 10 64-bit: Pro, Enterprise, or Education (Build 15063 or later).
   • Hyper-V and Containers Windows features must be enabled.
2. Download Docker Desktop for Windows:
   • Visit the Docker Hub and download the Docker Desktop installer.
3. Installation Process:
   • Run the installer and follow the instructions to install Docker Desktop on Windows.
   • Docker Desktop will start automatically once the installation is complete.
4. Verifying the Installation:
   • Open a command prompt or PowerShell, and run docker --version to check the Docker version.
   • Run docker run hello-world to verify that Docker can pull and run images.

Installing Docker on MacOS

Follow these steps to install Docker on MacOS:

1. System Requirements:
   • Mac hardware must be a 2010 or newer model, with Intel’s hardware support for memory management unit (MMU) virtualization, including Extended Page Tables (EPT) and Unrestricted Mode.
   • macOS must be version 10.14 or newer.
2. Downloading Docker Desktop for MacOS:
   • Go to the Docker Hub and download the Docker Desktop installer.
3. Installation Instructions:
   • Open the Docker.dmg file and drag the Docker icon to your Applications folder.
   • Run Docker from the Applications folder or Launchpad.
4. How to Verify if Docker is Running Correctly:
   • Open a terminal and type docker --version to see the installed Docker version.
   • Run docker run hello-world to ensure Docker can create and run containers.

Installing Docker on Linux

Docker can be installed on various Linux distributions. Here’s a general guide:

1. Installing Docker on Ubuntu, CentOS, Debian:
   • Update your package index using sudo apt-get update (Ubuntu/Debian) or sudo yum check-update (CentOS).
   • Install Docker using the package manager with sudo apt-get install docker-ce (Ubuntu/Debian) or sudo yum install docker-ce (CentOS).
   • Start the Docker service with sudo systemctl start docker.
2. Setting Up Docker to Run Without sudo:
   • Add your user to the ‘docker’ group with sudo usermod -aG docker $USER.
   • Log out and log back in so that your group membership is re-evaluated.
3. Verifying Docker Installation and Running a Test Container:
   • Verify installation by running docker --version.
   • Test Docker installation by running docker run hello-world.

How to Set Up Docker to Run Without sudo

The script below can be used to install Docker on a Raspberry Pi and configure it to run without sudo. This is useful for running Docker commands as a non-root user.

Note - use the sudo command to run the script as a superuser.

#!/bin/bash

# Define list of packages to install
pkgstoinstall=(libffi-dev libssl-dev python3 python3-pip)

# Update package cache and install packages
sudo apt-get update
sudo apt-get install -y "${pkgstoinstall[@]}"

# Download Docker convenience script if it doesn't exist
if [ ! -f /home/pi/get-docker.sh ]; then
    curl -fsSL https://get.docker.com -o /home/pi/get-docker.sh
fi

# Install Docker if not already installed
if [ ! -f /usr/bin/docker ]; then
    sh /home/pi/get-docker.sh
fi

# Add 'pi' user to the 'docker' group
sudo usermod -aG docker pi

# Unmask the Docker service
sudo systemctl unmask docker

# Fix permissions for Docker socket
sudo chmod 666 /var/run/docker.sock

# Install docker-compose if it doesn't exist
if [ ! -f /usr/local/bin/docker-compose ]; then
    sudo pip3 -v install docker-compose
fi

# Start Docker service
sudo systemctl start docker

This script automates the installation of Docker and its components on a Raspberry Pi, along with setting permissions to allow running Docker commands without requiring sudo access.