Docker - Getting Started Guide

Step 1 - Verify Portainer Works

Your server's IP address and root password are shown on the Server Details page in your client panel. Portainer starts automatically on first boot. Open your browser and go to:

https://your.server.ip:9443

Your browser will show a security warning about the self-signed certificate - this is normal, proceed to the site. Set a password for the admin account (minimum 12 characters). After that you will see the Portainer dashboard where you can manage containers, deploy stacks and monitor your Docker environment.

If you placed the server behind a VyOS router on a private network, you can either configure port forwarding (port 22 for SSH, port 9443 for Portainer, plus any ports your containers expose) or connect over a VPN and reach the server on its private IP.

Portainer Timeout

For security, Portainer gives you 5 minutes to set the password after the container starts. If you see "Your Portainer instance timed out", connect via SSH and restart the container:

ssh root@your.server.ip
docker restart portainer

Then open https://your.server.ip:9443 again and create your password.

Step 2 - Connect via SSH

For command-line Docker management, connect to your server:

ssh root@your.server.ip

Verify Docker is running:

docker --version
docker compose version
docker run hello-world

If you see "Hello from Docker!" - everything works.

Step 3 - Running Containers

Start a container from any image on Docker Hub:

# Run an Nginx web server on port 80
docker run -d --name webserver -p 80:80 nginx

# View running containers
docker ps

# Stop and remove the container
docker stop webserver
docker rm webserver

Step 4 - Docker Compose

Compose lets you define multi-container apps in a YAML file. Example - Nginx plus MySQL:

mkdir ~/myapp && cd ~/myapp

cat > docker-compose.yml <<'EOF'
services:
  web:
    image: nginx:alpine
    ports:
      - "80:80"
    volumes:
      - ./html:/usr/share/nginx/html
    depends_on:
      - db

  db:
    image: mysql:8.0
    environment:
      MYSQL_ROOT_PASSWORD: changeme
      MYSQL_DATABASE: myapp
    volumes:
      - db_data:/var/lib/mysql

volumes:
  db_data:
EOF

docker compose up -d

Useful Compose commands:

# View logs
docker compose logs -f

# Stop services
docker compose down

# Stop and remove volumes (deletes data!)
docker compose down -v

Disk Space

Docker images can use up disk space quickly. Keep an eye on it:

# Check overall disk usage
df -h /

# Check Docker-specific disk usage
docker system df

# Clean up unused images, containers and networks
docker system prune -a

Updates

To update Docker, Portainer and system packages:

# Update system packages and Docker
apt update && apt upgrade -y

# Update Portainer to the latest version
docker stop portainer
docker rm portainer
docker pull portainer/portainer-ce:latest
docker run -d --name portainer --restart=always \
  -p 9443:9443 \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -v portainer_data:/data \
  portainer/portainer-ce:latest

Firewall

SSH (port 22) and Portainer (port 9443) are open by default. When you publish container ports (like -p 80:80), they become accessible from the internet.

Check which ports your containers expose:

docker ps --format "table {{.Names}}\t{{.Ports}}"

Fail2Ban - Brute-Force Protection

Your server comes with Fail2Ban pre-configured to protect SSH from brute-force attacks.

Rule	Max Attempts	Ban Duration
SSH	5 failed logins	10 minutes

Useful commands:

# Check banned IPs
fail2ban-client status sshd

# Unban an IP
fail2ban-client set sshd unbanip 1.2.3.4

If you accidentally lock yourself out, connect via VNC console in your client panel and unban your IP.

Service Management

Docker runs as a systemd service. Common commands:

# Check service status
systemctl status docker

# Restart Docker
systemctl restart docker

# View Docker logs
journalctl -u docker -f

Server Credentials

The Portainer admin password is the one you set on first login at https://your.server.ip:9443. Docker itself has no separate credentials - access is controlled by the root user on the server.

Software Included

Component	Version
Ubuntu	24.04 LTS
Docker CE	29.3.0
Docker Compose	5.1.0
Docker Buildx	0.31.1
containerd	2.2.2
Portainer CE	2.39.0
Fail2Ban	1.0.2

• Docker Documentation: docs.docker.com
• Portainer Documentation: docs.portainer.io