Setting Up Docker on a VPS: Step-by-Step for Beginners

Docker lets you package applications and their dependencies into lightweight, portable containers that run identically on any Linux server. Deploying Docker on a VPS gives you the isolation of virtual machines without the overhead, making it ideal for hosting multiple web apps, APIs, or databases on a single server. This guide covers installing Docker on Ubuntu 24.04, running your first container, and securing the setup for production. Compare VPS plans on our site to find a provider with the resources to run multiple containers smoothly.

Prerequisites: Minimum VPS Specs for Docker

Docker itself is lightweight (the daemon uses ~100 MB RAM at idle), but your containers need memory too. For a typical setup hosting 3–5 containers:

Component	Minimum	Recommended
CPU	1 vCPU	2 vCPU
RAM	1 GB	2–4 GB
Storage	20 GB	40 GB NVMe
OS	Ubuntu 22.04+	Ubuntu 24.04 LTS

Step 1: Install Docker Engine

Use the official Docker repository for the latest stable release. Do not use apt install docker.io — that version is often outdated:

# Remove old versions (if any)
for pkg in docker.io docker-doc docker-compose docker-compose-v2 podman-docker containerd runc; do sudo apt-get remove $pkg; done

# Add Docker's official GPG key
sudo apt-get update
sudo apt-get install ca-certificates curl -y
sudo install -m 0755 -d /etc/apt/keyrings
sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
sudo chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository
# Replace "noble" with your Ubuntu codename if different
echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt-get update

# Install Docker packages
sudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin -y

Verify the installation: sudo docker run hello-world. If you see the Hello from Docker! message, everything is working.

Step 2: Run Docker Without Sudo (Post-Install)

By default, Docker requires sudo. Adding your user to the docker group eliminates this:

sudo usermod -aG docker $USER
# Log out and back in (or run: newgrp docker)
# Test:
docker run hello-world

Security note: The docker group grants root-equivalent privileges. On a multi-user VPS, consider using rootless Docker (Docker’s rootless mode) instead of the group approach.

Step 3: Deploy a Real Application with Docker Compose

Docker Compose lets you define multi-container applications in a YAML file. Here is a complete example that runs Nginx + PHP + MariaDB for a WordPress site:

# docker-compose.yml
version: '3.8'

services:
  db:
    image: mariadb:10.11
    volumes:
      - db_data:/var/lib/mysql
    restart: always
    environment:
      MYSQL_ROOT_PASSWORD: your_root_password
      MYSQL_DATABASE: wordpress
      MYSQL_USER: wpuser
      MYSQL_PASSWORD: wp_password

  wordpress:
    image: wordpress:latest
    ports:
      - "8080:80"
    restart: always
    environment:
      WORDPRESS_DB_HOST: db:3306
      WORDPRESS_DB_USER: wpuser
      WORDPRESS_DB_PASSWORD: wp_password
      WORDPRESS_DB_NAME: wordpress
    volumes:
      - wp_data:/var/www/html

volumes:
  db_data:
  wp_data:

Deploy with: docker compose up -d. Access WordPress at http://your-vps-ip:8080. Add a reverse proxy (Nginx on the host, or another container) to serve on port 443 with SSL.

Step 4: Secure Docker on Your VPS

Limit container resources: Use --memory and --cpus flags to prevent a single container from exhausting the host. Example: docker run --memory=512m --cpus=0.5 nginx.
Use read-only root filesystem: Add --read-only to containers that do not need write access to their filesystem.
Keep images updated: Run docker pull regularly and rebuild containers when security patches are released.
Scan images for vulnerabilities: docker scout quickview your-image (requires Docker Scout).
Never expose the Docker socket in a container unless absolutely required — it gives full host control.

Step 5: Enable Log Rotation

Container logs accumulate quickly and can fill your VPS disk. Configure log rotation globally by creating or editing /etc/docker/daemon.json:

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

Restart Docker: sudo systemctl restart docker. This limits each container to three 10 MB log files (30 MB max per container).

Docker transforms a general-purpose VPS into a flexible application platform. Once you have the basics running, explore Docker Swarm or Kubernetes for orchestration across multiple VPS nodes. For now, start with Compose — it handles the vast majority of single-server deployments without added complexity. Check out VPS plans on our site to find a provider that meets your container hosting needs.