{"id":441,"date":"2026-06-17T09:33:31","date_gmt":"2026-06-17T09:33:31","guid":{"rendered":"https:\/\/virtualserversvps.com\/blog\/?p=441"},"modified":"2026-07-20T22:19:33","modified_gmt":"2026-07-20T22:19:33","slug":"setting-up-docker-on-vps-step-by-step","status":"publish","type":"post","link":"https:\/\/virtualserversvps.com\/blog\/setting-up-docker-on-vps-step-by-step\/","title":{"rendered":"Setting Up Docker on a VPS: Step-by-Step with Compose, Resource Limits, and Security Hardening"},"content":{"rendered":"\n

Docker packages 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, deploying multi-container applications with Docker Compose, enforcing resource limits, and hardening your setup for production. For VPS plans that can handle containerized workloads efficiently, check our VPS performance tuning guides<\/a>.<\/p>\n\n\n\n

Prerequisites: Minimum VPS Specs for Docker<\/h2>\n\n\n\n

Docker’s daemon uses ~100 MB RAM at idle, but your containers need memory too. For a typical setup hosting 3\u20135 containers:<\/p>\n\n\n\n

Component<\/th>Minimum<\/th>Recommended<\/th><\/tr><\/thead>
CPU<\/td>1 vCPU<\/td>2+ vCPUs<\/td><\/tr>
RAM<\/td>1 GB<\/td>4 GB<\/td><\/tr>
Storage<\/td>20 GB<\/td>40 GB NVMe<\/td><\/tr>
OS<\/td>Ubuntu 22.04+<\/td>Ubuntu 24.04 LTS<\/td><\/tr>
Docker Engine<\/td>27.x<\/td>27.x+ with Compose v2<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Step 1: Install Docker Engine from Official Repos<\/h2>\n\n\n\n

Use the official Docker repository for the latest stable release. Do not use apt install docker.io<\/code> \u2014 that version lags behind by months and may miss critical security patches:<\/p>\n\n\n\n

# Remove old versions\nfor pkg in docker.io docker-doc docker-compose docker-compose-v2 podman-docker containerd runc; do sudo apt-get remove $pkg; done\n\n# Add Docker's official GPG key and repository\nsudo apt-get update\nsudo apt-get install ca-certificates curl -y\nsudo install -m 0755 -d \/etc\/apt\/keyrings\nsudo curl -fsSL https:\/\/download.docker.com\/linux\/ubuntu\/gpg -o \/etc\/apt\/keyrings\/docker.asc\nsudo chmod a+r \/etc\/apt\/keyrings\/docker.asc\necho \"deb [arch=$(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\nsudo apt-get update\n\n# Install Docker packages\nsudo apt-get install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin -y<\/code><\/pre>\n\n\n\n
Verify: sudo docker run hello-world<\/code>. You should see the Hello from Docker! message.<\/p>\n\n\n\n
Step 2: Post-Install \u2014 Run Docker Without Sudo<\/h2>\n\n\n\n
By default, Docker requires sudo. Add your user to the docker<\/code> group:<\/p>\n\n\n\n
sudo usermod -aG docker $USER\n# Log out and back in (or run: newgrp docker)\ndocker run hello-world<\/code><\/pre>\n\n\n\n
Security warning<\/strong>: The docker<\/code> group grants root-equivalent privileges. On multi-user VPS systems, use rootless Docker instead. See Docker’s rootless mode documentation<\/a>.<\/p>\n\n\n\n
Step 3: Multi-Container Apps with Docker Compose<\/h2>\n\n\n\n
Docker Compose defines multi-container applications in a YAML file. Below is a production-ready example running Nginx + PHP-FPM + MariaDB + Redis for a WordPress site, with resource limits and health checks built in:<\/p>\n\n\n\n
# docker-compose.yml\nservices:\n  db:\n    image: mariadb:10.11\n    restart: always\n    volumes:\n      - db_data:\/var\/lib\/mysql\n    environment:\n      MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}\n      MYSQL_DATABASE: wordpress\n      MYSQL_USER: wpuser\n      MYSQL_PASSWORD: ${MYSQL_PASSWORD}\n    deploy:\n      resources:\n        limits:\n          cpus: '1.0'\n          memory: 1024M\n        reservations:\n          cpus: '0.5'\n          memory: 512M\n    healthcheck:\n      test: [\"CMD\", \"mysqladmin\", \"ping\", \"-h\", \"localhost\"]\n      interval: 10s\n      timeout: 5s\n      retries: 3\n\n  wordpress:\n    image: wordpress:6-fpm-alpine\n    restart: always\n    depends_on:\n      db:\n        condition: service_healthy\n    environment:\n      WORDPRESS_DB_HOST: db:3306\n      WORDPRESS_DB_USER: wpuser\n      WORDPRESS_DB_PASSWORD: ${MYSQL_PASSWORD}\n      WORDPRESS_DB_NAME: wordpress\n    volumes:\n      - wp_data:\/var\/www\/html\n    deploy:\n      resources:\n        limits:\n          cpus: '0.5'\n          memory: 512M\n\n  nginx:\n    image: nginx:alpine\n    restart: always\n    ports:\n      - \"8080:80\"\n    volumes:\n      - wp_data:\/var\/www\/html\n      - .\/nginx\/default.conf:\/etc\/nginx\/conf.d\/default.conf:ro\n    depends_on:\n      - wordpress\n    deploy:\n      resources:\n        limits:\n          cpus: '0.25'\n          memory: 128M\n\n  redis:\n    image: redis:7-alpine\n    restart: always\n    command: redis-server --appendonly yes --maxmemory 128mb --maxmemory-policy allkeys-lru\n    volumes:\n      - redis_data:\/data\n    deploy:\n      resources:\n        limits:\n          memory: 256M\n\nvolumes:\n  db_data:\n  wp_data:\n  redis_data:<\/code><\/pre>\n\n\n\n
Deploy with: docker compose up -d<\/code>. Access WordPress at http:\/\/your-vps-ip:8080<\/code>. For production, add a reverse proxy (Caddy or Traefik) to handle SSL termination on port 443.<\/p>\n\n\n\n
Step 4: Container Resource Limits \u2014 Why They Matter<\/h2>\n\n\n\n
Without resource limits, a single runaway container can exhaust your VPS and take down every other service. Docker lets you constrain CPU, memory, and I\/O per container:<\/p>\n\n\n\n
# Hard memory limit (container is killed if exceeded)\ndocker run --memory=512m nginx\n\n# Soft reservation (container guaranteed at least 256 MB)\ndocker run --memory=512m --memory-reservation=256m nginx\n\n# CPU limits\ndocker run --cpus=0.5 nginx              # 50% of one core\ndocker run --cpus=2 --cpuset-cpus=0,1 nginx  # exactly cores 0 and 1\n\n# Block I\/O limits\ndocker run --device-read-bps \/dev\/nvme0n1:10mb --device-write-bps \/dev\/nvme0n1:5mb nginx<\/code><\/pre>\n\n\n\n
In Docker Compose, set these under the deploy.resources.limits<\/code> key as shown in Step 3. On a 4 GB VPS running five containers, resource limits prevent a memory leak in one container from OOM-killing the entire server.<\/p>\n\n\n\n
Step 5: Security Best Practices for Docker on VPS<\/h2>\n\n\n\n