Install Docker on a Linux VPS

This guide explains how to install Docker and Docker Compose on your Linux VPS. Docker is a containerization platform that allows you to create, deploy and run applications in isolated containers, making application deployment and management easier.

📋 Prerequisites

• A Linux VPS with root or sudo access
• Ubuntu 20.04+ or Debian 11+ (or CentOS 7+/RHEL 7+)
• At least 1 GB of RAM (2 GB recommended)
• A stable Internet connection

💡 Infrastructure Recommendation

Docker requires fast disks for compilation and intensive I/O operations. We recommend our NVMe VPS for optimal performance when using Docker. NVMe drives offer speeds up to 10x faster than traditional SSDs, significantly accelerating Docker image builds and container startup times.

⚠️ Important before installation

• Check your system : Docker requires a 64-bit system
• Backup your data : Installation may modify some system configurations
• Installation time : Installation typically takes 5 to 10 minutes

🔧 Installation on Ubuntu/Debian

Step 1: Update the system

Bash
1# Update package list
2sudo apt update
3
4# Update installed packages
5sudo apt upgrade -y

Step 2: Install dependencies

Bash
1# Install necessary packages
2sudo apt install -y \
3    ca-certificates \
4    curl \
5    gnupg \
6    lsb-release

Step 3: Add Docker's official GPG key

Bash
1# Create directory for keys
2sudo install -m 0755 -d /etc/apt/keyrings
3
4# Download and add GPG key
5curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
6
7# Set correct permissions
8sudo chmod a+r /etc/apt/keyrings/docker.gpg

Step 4: Configure Docker repository

Bash
# Add 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

Step 5: Install Docker Engine

Bash
1# Update package list
2sudo apt update
3
4# Install Docker Engine, containerd and Docker Compose
5sudo apt install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

Step 6: Verify installation

Bash
1# Verify Docker is installed correctly
2sudo docker --version
3
4# Verify Docker Compose is installed
5sudo docker compose version

🔧 Installation on CentOS/RHEL

Step 1: Update the system

Bash
# Update packages
sudo yum update -y

Step 2: Install dependencies

Bash
# Install necessary packages
sudo yum install -y yum-utils

Step 3: Add Docker repository

Bash
# Add Docker repository
sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

Step 4: Install Docker Engine

Bash
# Install Docker Engine, containerd and Docker Compose
sudo yum install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

Step 5: Start Docker

Bash
1# Start Docker service
2sudo systemctl start docker
3
4# Enable Docker on boot
5sudo systemctl enable docker

Step 6: Verify installation

Bash
1# Verify Docker is installed correctly
2sudo docker --version
3
4# Verify Docker Compose is installed
5sudo docker compose version

👤 Step 7: Configure permissions (Important)

By default, Docker requires root privileges. To run Docker without sudo, add your user to the docker group:

Bash
1# Add your user to docker group
2sudo usermod -aG docker $USER
3
4# Apply changes (logout/login required)
5newgrp docker

Verify permissions

Bash
# Test Docker without sudo
docker run hello-world

If this command works without error, Docker is correctly configured!

🧪 Step 8: Test Docker

Run a test container

Bash
# Run Hello World container
docker run hello-world

This command will:

1. Download the hello-world image from Docker Hub
2. Create a container from this image
3. Run the container
4. Display a confirmation message

Check containers

Bash
1# List running containers
2docker ps
3
4# List all containers (including stopped)
5docker ps -a
6
7# List Docker images
8docker images

🐙 Step 9: Install Docker Compose (if not included)

If Docker Compose was not installed with Docker Engine, install it separately:

On Ubuntu/Debian

Bash
1# Download Docker Compose
2sudo curl -L "https://github.com/docker/compose/releases/latest/download/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
3
4# Make executable
5sudo chmod +x /usr/local/bin/docker-compose
6
7# Verify installation
8docker-compose --version

On CentOS/RHEL

Bash
1# Download Docker Compose
2sudo curl -L "https://github.com/docker/compose/releases/latest/download/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
3
4# Make executable
5sudo chmod +x /usr/local/bin/docker-compose
6
7# Verify installation
8docker-compose --version

📦 Essential Docker commands

Image management

Bash
1# Download an image
2docker pull image-name:tag
3
4# List images
5docker images
6
7# Remove an image
8docker rmi image-name
9
10# Clean unused images
11docker image prune -a

Container management

Bash
1# Create and start a container
2docker run image-name
3
4# Create a container in background (detached)
5docker run -d image-name
6
7# List running containers
8docker ps
9
10# Stop a container
11docker stop container-id
12
13# Start a stopped container
14docker start container-id
15
16# Restart a container
17docker restart container-id
18
19# Remove a container
20docker rm container-id
21
22# View container logs
23docker logs container-id
24
25# Execute a command in a running container
26docker exec -it container-id /bin/bash

Docker Compose

Bash
1# Start services defined in docker-compose.yml
2docker compose up
3
4# Start in background
5docker compose up -d
6
7# Stop services
8docker compose down
9
10# View logs
11docker compose logs
12
13# Rebuild images
14docker compose build

🔒 Securing Docker

Configure Docker daemon (optional)

Create or modify /etc/docker/daemon.json:

Bash
sudo nano /etc/docker/daemon.json

Add the following configuration:

JSON
1{
2  "log-driver": "json-file",
3  "log-opts": {
4    "max-size": "10m",
5    "max-file": "3"
6  }
7}

Restart Docker:

Bash
sudo systemctl restart docker

Limit Docker access

By default, users in the docker group have root-equivalent privileges. For more security, you can:

1. Only give access to trusted users
2. Use Docker rootless (advanced installation)
3. Configure security policies via AppArmor or SELinux

🔄 Update Docker

On Ubuntu/Debian

Bash
1# Update packages
2sudo apt update
3
4# Update Docker
5sudo apt upgrade docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

On CentOS/RHEL

Bash
# Update Docker
sudo yum update docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

🗑️ Uninstall Docker

If you want to uninstall Docker:

On Ubuntu/Debian

Bash
1# Stop Docker
2sudo systemctl stop docker
3
4# Uninstall packages
5sudo apt purge docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin docker-ce-rootless-extras
6
7# Remove images, containers and volumes
8sudo rm -rf /var/lib/docker
9sudo rm -rf /var/lib/containerd

On CentOS/RHEL

Bash
1# Stop Docker
2sudo systemctl stop docker
3
4# Uninstall packages
5sudo yum remove docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin docker-ce-rootless-extras
6
7# Remove images, containers and volumes
8sudo rm -rf /var/lib/docker
9sudo rm -rf /var/lib/containerd

❓ Common Issues

Error "Cannot connect to the Docker daemon"

Solution:

Bash
1# Check Docker service is started
2sudo systemctl status docker
3
4# Start Docker if necessary
5sudo systemctl start docker
6
7# Check you are in docker group
8groups

Error "Permission denied"

Solution:

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

# Log out and log back in

Docker is slow

Possible solutions:

• Check disk space: df -h
• Clean unused images: docker system prune -a
• Check available RAM: free -h

📝 Example: Deploy a simple application

Create a docker-compose.yml file

Bash
1# Create a directory for your project
2mkdir my-project
3cd my-project
4
5# Create docker-compose.yml file
6nano docker-compose.yml

Example content:

YAML
1version: '3.8'
2
3services:
4  web:
5    image: nginx:latest
6    ports:
7      - "80:80"
8    volumes:
9      - ./html:/usr/share/nginx/html
10    restart: unless-stopped

Start the application

Bash
1# Start services
2docker compose up -d
3
4# Verify container is running
5docker ps

📞 Need Help?

If you encounter difficulties installing Docker, please contact Infrawire support. Our team is available to help you.

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Note : Docker is a powerful tool that greatly simplifies application deployment. Take time to understand the basic concepts before deploying applications in production.