Installing Docker

Docker is available for Windows, macOS, and Linux. This lesson covers installation on each platform and verification steps.

Installation Options

Docker offers two main products:

Product	Use Case	Platforms
Docker Desktop	Development	Windows, macOS, Linux
Docker Engine	Production servers	Linux only

Installing Docker Desktop

Docker Desktop is the recommended option for developers. It includes Docker Engine, Docker CLI, Docker Compose, and a graphical interface.

macOS Installation

1. Download Docker Desktop from docker.com/products/docker-desktop
2. Open the .dmg file and drag Docker to Applications
3. Launch Docker from Applications
4. Complete setup by following the prompts

System Requirements:

• macOS 12 or newer
• Apple Silicon (M1/M2/M3) or Intel chip
• 4GB RAM minimum

Windows Installation

1. Enable WSL 2 (Windows Subsystem for Linux 2)

   wsl --install
   

2. Download Docker Desktop from docker.com
3. Run the installer and follow prompts
4. Restart your computer when prompted
5. Launch Docker Desktop

System Requirements:

• Windows 10/11 (64-bit)
• WSL 2 enabled
• 4GB RAM minimum

Linux Installation (Ubuntu/Debian)

For Linux, you can install Docker Engine directly:

# Update package index
sudo apt-get update

# Install prerequisites
sudo apt-get install ca-certificates curl gnupg

# Add Docker's official GPG key
sudo install -m 0755 -d /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | \
  sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
sudo chmod a+r /etc/apt/keyrings/docker.gpg

# Set up the repository
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] \
  https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

# Install Docker Engine
sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io docker-compose-plugin

Verifying Installation

After installation, verify Docker is working correctly:

# Check Docker version
docker --version

# Expected output:
# Docker version 24.0.x, build xxxxxxx

# Check Docker Compose version
docker compose version

# Expected output:
# Docker Compose version v2.x.x

# Run the hello-world container
docker run hello-world

The hello-world container output confirms Docker is properly installed:

Hello from Docker!
This message shows that your installation appears to be working correctly.
...

Post-Installation Steps (Linux)

On Linux, add your user to the docker group to run Docker without sudo:

# Create docker group (if it doesn't exist)
sudo groupadd docker

# Add your user to docker group
sudo usermod -aG docker $USER

# Apply the group change
newgrp docker

# Verify you can run without sudo
docker run hello-world

Docker Desktop Features

Docker Desktop includes several useful features:

GUI Dashboard

• View running containers
• Manage images and volumes
• Monitor resource usage
• Access logs and terminal

Extensions

• Add functionality through Docker extensions
• Popular extensions: Disk Usage, Logs Explorer, Portainer

Settings

• Resource allocation (CPU, memory, disk)
• Network configuration
• Kubernetes integration
• Experimental features

Resource Configuration

Configure resources in Docker Desktop settings:

Resource	Development	Light Use
CPUs	4+	2
Memory	8GB+	4GB
Disk	64GB+	32GB
Swap	2GB	1GB

Common Installation Issues

Docker daemon not running

# Check Docker service status
sudo systemctl status docker

# Start Docker service
sudo systemctl start docker

# Enable on boot
sudo systemctl enable docker

Permission denied

# On Linux, ensure you're in the docker group
groups $USER

# If docker is not listed, add yourself
sudo usermod -aG docker $USER
# Log out and back in for changes to take effect

WSL 2 issues (Windows)

# Update WSL
wsl --update

# Set default version to 2
wsl --set-default-version 2

Uninstalling Docker

macOS

1. Open Docker Desktop
2. Select "Troubleshoot" → "Uninstall"
3. Drag Docker from Applications to Trash

Windows

1. Open Settings → Apps
2. Find Docker Desktop
3. Click Uninstall

Linux

sudo apt-get purge docker-ce docker-ce-cli containerd.io
sudo rm -rf /var/lib/docker
sudo rm -rf /var/lib/containerd

Key Takeaways

• Docker Desktop is recommended for development on Windows and macOS
• Linux users can install Docker Engine directly
• Always verify installation with docker --version and docker run hello-world
• On Linux, add your user to the docker group for convenience
• Configure resource limits based on your workload needs