How to run Docker on a VPS

Docker packages an application and everything it needs into a portable container that runs the same way anywhere. On a VPS, Docker makes deployments clean and repeatable: no more "works on my machine," easy rollbacks, and multiple isolated apps on one server. Here's how to get running.

Step 1: Install Docker

On a fresh Ubuntu VPS, install Docker from the official repository:

sudo apt update
sudo apt 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
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
sudo apt update
sudo apt install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin -y

Verify:

sudo docker run hello-world

Step 2: Run Docker without sudo

Add your user to the docker group so you don't type sudo every time:

sudo usermod -aG docker $USER

Log out and back in for it to take effect.

Step 3: Run your first real container

Let's run an Nginx web server in seconds:

docker run -d --name web -p 80:80 nginx

The -d runs it in the background, -p 80:80 maps the container's port 80 to the server's port 80. Visit http://YOUR_SERVER_IP and you'll see Nginx. Manage it with:

docker ps
docker logs web
docker stop web
docker rm web

Step 4: Persist data with volumes

Containers are ephemeral — data inside them vanishes when they're removed. Volumes keep data outside the container:

docker run -d --name db -v db-data:/var/lib/postgresql/data -e POSTGRES_PASSWORD=secret postgres

The named volume db-data survives container restarts and recreations.

Step 5: Multi-service apps with Compose

Real apps have several parts — a web app, a database, a cache. Docker Compose describes them all in one file. Create docker-compose.yml:

services:
  app:
    image: my-app:latest
    ports:
      - "3000:3000"
    environment:
      DATABASE_URL: postgres://user:secret@db:5432/mydb
    depends_on:
      - db
  db:
    image: postgres:16
    environment:
      POSTGRES_USER: user
      POSTGRES_PASSWORD: secret
      POSTGRES_DB: mydb
    volumes:
      - db-data:/var/lib/postgresql/data

volumes:
  db-data:

Bring the whole stack up:

docker compose up -d

Compose creates a private network so app reaches db by name. Tear it down with docker compose down.

Step 6: Put HTTPS in front

Don't expose app ports directly. Run a reverse proxy — Caddy in a container gives you automatic HTTPS, or use Nginx on the host. A minimal Caddy service in Compose:

  caddy:
    image: caddy:latest
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./Caddyfile:/etc/caddy/Caddyfile

Step 7: Firewall

Only open what you actually serve:

sudo ufw allow OpenSSH
sudo ufw allow 80/tcp
sudo ufw allow 443/tcp
sudo ufw enable

Housekeeping

Docker images and volumes accumulate. Reclaim space periodically:

docker system prune -a

Be careful — that removes unused images and stopped containers.

Why Docker suits a VPS

You get root, a full Linux kernel, and dedicated resources — exactly what Docker wants. A Nxeon NVMe VPS pulls images fast and runs containers with real, guaranteed CPU and RAM, unlike constrained shared hosts where Docker isn't even allowed. Package your app once and deploy it identically every time.