Installing Docker on a VPS: step-by-step guide
Installing Docker on a VPS is one of the first steps many system administrators and developers take when setting up a new server. Docker makes it possible to run applications in isolated containers, which ensures consistency, scalability, and easy management. In this complete guide you learn step by step how to install Docker on a VPS, from preparing your server to running your first container.
What is Docker and why install Docker on a VPS?
Docker is an open-source platform that makes it possible to package applications in containers. A container contains everything an application needs to run: the code, runtime, libraries, and system tools. This makes it easy to move applications between different environments without compatibility problems. When you install Docker on a VPS, you get access to a powerful ecosystem for managing web applications.
Benefits of Docker on a VPS
- Isolation - each application runs in its own container without conflicts
- Consistency - the same container runs identically on development, test, and production environments
- Efficient use of resources - containers are lighter than virtual machines
- Fast deployment - new applications are operational in seconds
- Easy scalability - duplicating containers is simple
- Version control - easy rollback to earlier versions
System requirements for installing Docker on a VPS
Before you install Docker on a VPS, your server must meet certain minimum requirements. Here is an overview of what you need:
| Component | Minimum | Recommended | Explanation |
|---|---|---|---|
| RAM | 1 GB | 2+ GB | More RAM = more containers at the same time |
| CPU | 1 core | 2+ cores | 64-bit processor required |
| Storage | 10 GB | 40+ GB | SSD strongly recommended for performance |
| OS | Ubuntu 22.04+ | Ubuntu 24.04 LTS | Debian, CentOS, AlmaLinux also supported |
| Kernel | 3.10+ | 5.x+ | Modern kernels offer better container support |
Don't have a VPS yet? Take a look at our guide about choosing a VPS provider to select the right server for your Docker environment.
Step 1: Prepare the VPS
The first step in installing Docker on a VPS is preparing your server. Log in over SSH and carry out the following preparatory tasks. If you are not yet familiar with SSH, read our guide about server connections.
Update the system
Always start by updating your system to the latest packages. On Ubuntu/Debian you do this with apt update and apt upgrade. This ensures that all security patches are applied and that you have the latest versions of dependencies.
Install the required packages
Docker needs a number of basic packages for the installation. These are packages that make it possible to use repositories over HTTPS: apt-transport-https, ca-certificates, curl, and gnupg. These packages ensure a secure download of Docker from the official repository.
Remove old Docker versions
If there is an older version of Docker on your server, remove it first. Older packages may be called docker, docker.io, or docker-engine. Removing these versions prevents conflicts with the new installation.
Step 2: Add the Docker repository
Docker is not installed from the standard Ubuntu/Debian repositories, but from the official Docker repository. This guarantees that you always get the latest and most stable version.
Add the GPG key
Download the official Docker GPG key and add it to your system. This key verifies that the packages you download are authentic and have not been tampered with. Store the key in /etc/apt/keyrings/ for the latest best practice.
Configure the repository
Add the Docker repository to your sources list. Use the architecture of your system (usually amd64 for x86_64 servers) and the codename of your Ubuntu/Debian version. After adding the repository, run an update again so your system can find the new packages.
Step 3: Install Docker Engine
Now that you have configured the repository, you can install the actual Docker Engine. The process of installing Docker on a VPS involves three packages: docker-ce (the Docker Engine), docker-ce-cli (the command-line interface), and containerd.io (the container runtime).
Verify the installation
After the installation you check whether Docker works correctly by requesting the version with docker --version and running a test container with docker run hello-world. If you see the hello-world message, Docker has been installed successfully on your VPS.
Use Docker without sudo
By default, Docker requires root privileges. To run Docker commands without sudo, add your user to the docker group. After this you need to log out and log back in for the change to take effect. Note: this effectively gives your user root privileges through Docker, so be careful with this on production servers.
Step 4: Install Docker Compose
Docker Compose is an indispensable tool that lets you define and manage multi-container applications with a single configuration file. When you install Docker on a VPS, Docker Compose is part of it by default.
What is Docker Compose?
With Docker Compose you define your complete application stack in a docker-compose.yml file. This file describes which containers you need, how they are connected to each other, and which configuration they use. With a single command you then start all containers at once.
Install Docker Compose
The latest version of Docker Compose (V2) is installed as a Docker plugin. With recent Docker installations, Compose V2 is often already included. Check this with docker compose version. If it is missing, install the docker-compose-plugin package through apt.
Step 5: Configure Docker for production
After installing Docker on a VPS, there are important configuration steps needed to make Docker suitable for production use. Default settings are not always optimal for a production environment.
Configure logging
Docker containers generate logs that can grow indefinitely by default. Configure log rotation in the Docker daemon configuration file (/etc/docker/daemon.json) to prevent your disk from filling up. Set a maximum size of, for example, 10 MB per log file and keep a maximum of 3 files.
Choose a storage driver
The default storage driver (overlay2) is the best choice for most situations. Check which driver is active with docker info. On older systems it can happen that a less efficient driver is used, which affects performance.
Configure the network
Docker creates a bridge network by default. For production you often want to create custom networks that let your containers communicate in a controlled way. Custom networks also offer automatic DNS resolution between containers, which simplifies management.
Step 6: Run your first container
Now that Docker is installed and configured, it is time to run your first real container. As an example, let's start an Nginx web server.
Start an Nginx container
With the docker run command you start an Nginx container. With the -d flag the container runs in the background (detached mode). With the -p flag you map port 80 of the container to port 80 of your VPS, so the web server is reachable through the IP address of your server. The --name flag gives the container a recognizable name for easy management.
Manage the container
Important commands for managing your Docker containers are:
- docker ps - show all running containers
- docker ps -a - show all containers including stopped ones
- docker stop [name] - stop a container
- docker start [name] - start a stopped container
- docker restart [name] - restart a container
- docker logs [name] - view the logs of a container
- docker exec -it [name] bash - open a shell in a running container
Practical Docker Compose examples
Below you will find commonly used Docker Compose configurations for websites and web applications.
WordPress with MySQL
One of the most popular use cases is running WordPress in Docker. With Docker Compose you define a WordPress container and a MySQL container that work together. The WordPress container automatically connects to the database container through the Docker network.
Node.js application
For Node.js applications you create a Dockerfile that contains your application and dependencies, and you use Docker Compose to orchestrate the application together with any databases and cache servers.
Reverse proxy with Nginx
When running multiple web applications in Docker, a reverse proxy is essential. Nginx Proxy Manager and Traefik are popular options that automatically request SSL certificates through Let's Encrypt and route traffic to the right container.
Docker security on your VPS
After installing Docker on a VPS, security is a crucial point of attention. Docker containers share the kernel with the host system, which means a security flaw in Docker can potentially compromise the entire system.
Security best practices
- Never run containers as the root user (use USER in the Dockerfile)
- Use only official and trusted Docker images
- Scan images regularly for vulnerabilities with tools such as Trivy
- Limit container resources with memory and CPU limits
- Use read-only filesystems where possible
- Always keep Docker itself up to date
- Configure the firewall to open only the necessary ports
Combine Docker security with the general server security measures from our guide about securing your website.
Common problems when installing Docker on a VPS
When installing Docker on a VPS you can run into various problems. Here are the most common issues and their solutions:
Permission denied
This happens if you run Docker commands without the right privileges. Add your user to the docker group or use sudo. Don't forget to log out and log back in after adding to the group.
Port conflicts
If another service is already running on a port, Docker cannot use it. Check which ports are in use and choose a different port for your container, or stop the conflicting service.
Insufficient storage space
Docker images and containers can take up a lot of space. Use docker system prune regularly to clean up unused images, containers, and volumes. Actively monitor your disk usage to prevent problems.
Summary and next steps
You have now successfully installed Docker on a VPS and run your first containers. Docker opens up a world of possibilities for managing web applications on your VPS. The next steps you can take are setting up automatic container updates, configuring monitoring with tools such as Portainer or ctop, implementing CI/CD pipelines for automatic deployments, and exploring container orchestration with Docker Swarm. With Docker on your VPS you are ready to run modern web applications in an efficient, scalable, and manageable way. Also take a look at our guide about VPS hosting in the Netherlands for the best servers to run Docker on.
Installing Docker on a VPS: network configuration and security
After the basic installation of Docker on your VPS, a good network configuration is essential. Docker creates a bridge network by default, but for production environments you need more control over how containers communicate with each other and the outside world.
Docker network types explained
| Network type | Use | Isolation | Performance |
|---|---|---|---|
| Bridge (default) | Containers on the same host | Good | Good |
| Host | Maximum performance needed | None | Best |
| Overlay | Multi-host (Docker Swarm) | Good | Average |
| Macvlan | Containers as physical devices | Full | Good |
| None | No network needed | Full | N/A |
For production, always create a user-defined bridge network instead of the default bridge network. This offers automatic DNS resolution between containers (you can use container names as a hostname) and better isolation. Use the command docker network create my-network to create a new network.
Docker Compose for production on your VPS
Docker Compose is indispensable when you run multiple services on your VPS. With a single YAML file you define your complete application stack. For installing Docker on a VPS in production, Docker Compose is the recommended approach.
A typical web application stack in Docker Compose contains:
- Reverse proxy: Nginx or Traefik for SSL termination and load balancing
- Application: your web application in one or more containers
- Database: MySQL, PostgreSQL, or MongoDB in its own container
- Cache: Redis or Memcached for session storage and caching
- Monitoring: Prometheus and Grafana for server monitoring
Always use specific version numbers for your images instead of the latest tag. This prevents unexpected updates that can break your application. Store sensitive configuration in Docker secrets or environment files that are not in your Git repository.
Docker security on your VPS: best practices
Docker containers are not fully isolated from the host system by default. Without additional measures, vulnerabilities in containers can lead to the compromise of your entire VPS. Follow these best practices for a secure Docker environment:
- Don't run containers as root: use the USER directive in your Dockerfile to specify a non-root user.
- Limit container resources: set limits for CPU and memory with --memory and --cpus to prevent denial-of-service.
- Use read-only filesystems: mount the container filesystem as read-only where possible with the --read-only flag.
- Scan images for vulnerabilities: use tools such as Trivy or Docker Scout to detect known vulnerabilities in your images.
- Limit capabilities: remove unnecessary Linux capabilities with --cap-drop ALL and add only the necessary capabilities.
Don't forget to also secure the underlying VPS. Follow the steps in our VPS security checklist and make sure you have a well-configured firewall. Use SSH keys instead of passwords for server access and keep the operating system up to date with the latest security patches.
Installing Docker on a VPS: logging and troubleshooting
Effective log management is crucial when you install Docker on a VPS and run it in production. Docker containers generate logs that are essential for debugging problems, monitoring application health, and detecting security incidents.
By default, Docker writes logs to JSON files on the host. With long-running containers, these log files can grow enormously and fill up your disk space. Configure log rotation in your Docker daemon configuration by setting a maximum file size and the number of files to keep. A maximum size of 10 megabytes with three rotating files is a good starting configuration for most use cases.
For production environments with multiple containers, a centralized logging solution is indispensable. The ELK stack (Elasticsearch, Logstash, Kibana) or the lighter alternative Loki with Grafana collects logs from all containers in a central location. This makes it possible to recognize patterns across multiple services, which is crucial when debugging microservice architectures.
Docker VPS: volumes and persistent storage
Data in Docker containers is ephemeral by default: when a container is removed, all data disappears with it. For production workloads on your VPS, persistent storage through Docker volumes is essential. Volumes are managed by Docker and exist independently of containers. They survive the stopping, restarting, and even removal of containers. Use named volumes for databases and other stateful services. Make regular backups of your volumes, preferably through an automated script that copies the data to an external storage location. Bind mounts are an alternative in which you link a directory on the host system directly to a container. This is handy for development and configuration files, but volumes are preferable for production data because of better isolation and portability between different hosts.
Docker on your VPS: automatic updates and maintenance
Maintaining a Docker environment on your VPS requires attention to both Docker itself and the images you use. Outdated images often contain known security vulnerabilities that are actively exploited by attackers. A structured update policy is essential after installing Docker on your VPS.
Automate the checking and updating of Docker images with tools such as Watchtower. Watchtower monitors your running containers and updates them automatically when a new version of the used image is available. Configure Watchtower to only carry out updates during maintenance windows, for example at night when traffic on your website is minimal. For production environments, a more controlled approach is safer: use a CI/CD pipeline that first tests new images in a staging environment before they are rolled out to production.
Clean up unused Docker resources regularly. Old images, stopped containers, and unused volumes take up disk space that can gradually build up. The command docker system prune removes all unused resources at once, but use this carefully in production. Schedule a monthly maintenance session to clean up your Docker environment, update images, and review the configuration.
Docker on your VPS: resources and learning materials
After installing Docker on your VPS, ongoing knowledge building is essential to manage your container environment professionally. The official Docker documentation at docs.docker.com is the best starting point with extensive guides, tutorials, and reference material. The Docker community forums and the Docker channel on Stack Overflow offer answers to specific problems you run into. For deeper knowledge about container security and production best practices, the CIS Docker Benchmark and the NIST Application Container Security Guide are valuable resources that are regularly updated with the latest guidelines. Invest time in learning container orchestration with Docker Compose and eventually Kubernetes as your infrastructure grows.
