Setting Up Docker on Ubuntu

Docker is the standard way to run self-hosted apps. This guide gets Docker and Docker Compose installed on Ubuntu 22.04 or 24.04. The steps work on any Ubuntu-based VPS.

Prerequisites

• A fresh Ubuntu 22.04 or 24.04 server
• SSH access as a user with sudo
• 5–10 minutes

Step 1: SSH In and Update

ssh root@your-server-ip
# or: ssh your-user@your-server-ip

Update the system:

sudo apt update && sudo apt upgrade -y

Step 2: Install Docker via Official Script

The Docker team provides a convenience script that adds their repo and installs the latest version. For production, you could pin a specific version—for most self-hosting use cases, the script is fine.

curl -fsSL https://get.docker.com -o get-docker.sh
sudo sh get-docker.sh

Add your user to the docker group so you don't need sudo for every Docker command:

sudo usermod -aG docker $USER

Log out and back in (or run newgrp docker) for the group change to take effect.

Step 3: Install Docker Compose Plugin

Docker Compose v2 is a plugin, not a standalone binary. Install it:

sudo apt install docker-compose-plugin -y

Verify:

docker compose version

You should see something like Docker Compose version v2.x.x.

Step 4: Verify Installation

docker run hello-world

You should see "Hello from Docker!" and a message that your installation appears to be working.

Check that the Docker daemon starts on boot:

sudo systemctl enable docker
sudo systemctl status docker

Status should show active (running).

Basic Docker Commands

You'll use these constantly:

Command	Purpose
docker compose up -d	Start services in the background
docker compose down	Stop and remove containers
docker compose ps	List running containers
docker compose logs -f	Follow logs
docker compose pull	Pull latest images
docker compose up -d --pull always	Pull and restart with new images

Example: Run a Simple App

Create a directory and a minimal Compose file:

mkdir -p ~/test-app && cd ~/test-app

Create docker-compose.yml:

services:
  nginx:
    image: nginx:alpine
    ports:
      - "8080:80"

Run it:

docker compose up -d

Visit http://your-server-ip:8080 and you should see the default Nginx page. Stop it with docker compose down.

Troubleshooting

Permission denied when running docker: Make sure you're in the docker group and have logged out/in. Or use sudo docker.

Port already in use: Another service is using the port. Change the port mapping (e.g., 8081:80) or stop the conflicting service.

Out of disk space: Docker images and containers use disk. Run docker system prune -a to remove unused images (warning: removes all unused images, not just old ones).

Next Steps

With Docker installed, you're ready to set up a reverse proxy. The next guide covers configuring Traefik so you can serve multiple apps on different subdomains with automatic HTTPS.