Step-by-Step Guide: Installing WordPress Using Docker Compose

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WordPress CMS (Content Management System) is a widely used open-source platform that enables users to create, manage, and publish digital content, primarily for websites and blogs. Initially released in 2003, WordPress has grown to become the world’s most popular CMS, powering over 40% of all websites on the internet. It offers a user-friendly interface that allows individuals with little to no coding experience to build and maintain professional-quality websites. WordPress is highly customizable, with thousands of themes and plugins available to extend its functionality, catering to a wide range of needs from simple blogs to complex e-commerce sites. Its strong community support, regular updates, and extensive documentation make it a reliable and versatile choice for both beginners and experienced developers.

Docker is an open-source platform designed to automate the deployment, scaling, and management of applications within lightweight, portable containers. Introduced in 2013, Docker revolutionized software development by providing a consistent environment for applications to run regardless of where they are deployed, be it on a developer’s local machine,
on-premises data centers, or in the cloud. Containers bundle an application with all its dependencies, libraries, and configuration files, ensuring consistent performance across different environments. This containerization simplifies the development workflow, enhances collaboration, and increases efficiency by allowing developers to create, share, and run applications seamlessly. Docker’s ecosystem includes tools and services for container orchestration, such as Docker Swarm and Kubernetes, which facilitate
the management of large-scale container deployments, making it a cornerstone technology in modern DevOps practices.

This guide will walk you through the process of installing WordPress using Docker and Docker Compose. Docker simplifies the installation by providing a consistent setup that can be deployed across multiple servers. In addition, we will also install phpMyAdmin for database management and an Nginx proxy server to serve the website via SSL.

Prerequisites

  • A Linux server with a non-root user having sudo privileges. This tutorial uses Ubuntu 24.04.
  • A fully qualified domain name (FQDN) pointing to your server. This guide uses example.com for the WordPress site and
    phpmyadmin.example.com for the phpMyAdmin website.
  • Ensure your server is updated: 
    $ sudo apt update
  • Install essential utility packages: 
    $ sudo apt install wget curl nano software-properties-common dirmngr apt-transport-https gnupg gnupg2 ca-certificates lsb-release ubuntu-keyring unzip -y

Step 1 – Configure Firewall

Configure the firewall using UFW, which is available by default in Ubuntu:

Check firewall status:

$ sudo ufw status

Expected output:

Status: inactive

Allow SSH, HTTP, and HTTPS ports:

$ sudo ufw allow OpenSSH
$ sudo ufw allow http
$ sudo ufw allow https

Enable the firewall:

$ sudo ufw enable

Status check after enabling:

$ sudo ufw status

Step 2 – Install Docker and Docker Compose

To install the latest Docker version on Ubuntu 22.04:

Import Docker’s GPG key:

$ curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg

Create a Docker repository file:

$ echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \
  $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

Update the repository list and install Docker:

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

Verify Docker is running:

$ sudo systemctl status docker

Add your user to the Docker group to avoid sudo usage:

$ sudo usermod -aG docker $(whoami)

Log out and back in or use:

$ su - ${USER}

Confirm Docker group membership:

$ groups

Step 3 – Create Docker Compose File for WordPress

We’ll install WordPress in the /opt directory, but feel free to use /var, /home, or another suitable path:

cd /opt

Create and navigate to a WordPress configuration directory:

$ mkdir wordpress
$ cd wordpress

Create and edit the Docker Compose file:

$ nano docker-compose.yml

Paste the following configuration in the file:


services:
  wp:
    image: wordpress:latest
    container_name: wordpress-app
    restart: unless-stopped
    expose:
      - 8080
    volumes:
      - ./config/php.conf.ini:/usr/local/etc/php/conf.d/conf.ini
      - ./wp-app:/var/www/html
    environment:
      WORDPRESS_DB_HOST: db
      WORDPRESS_DB_NAME: "${DB_NAME}"
      WORDPRESS_DB_USER: "${DB_USER_NAME}"
      WORDPRESS_DB_PASSWORD: "${DB_USER_PASSWORD}"
      VIRTUAL_HOST: example.com
      LETSENCRYPT_HOST: example.com
    depends_on:
      - db
    links:
      - db

  wpcli:
    image: wordpress:cli
    container_name: wpcli_app
    volumes:
      - ./config/php.conf.ini:/usr/local/etc/php/conf.d/conf.ini
      - ./wp-app:/var/www/html
    environment:
      WORDPRESS_DB_HOST: db
      WORDPRESS_DB_NAME: "${DB_NAME}"
      WORDPRESS_DB_USER: "${DB_USER_NAME}"
      WORDPRESS_DB_PASSWORD: "${DB_USER_PASSWORD}"
    depends_on:
      - db
      - wp

  pma:
    image: phpmyadmin/phpmyadmin
    container_name: pma
    restart: unless-stopped
    environment:
      PMA_HOST: db
      PMA_PORT: 3306
      MYSQL_ROOT_PASSWORD: "${DB_ROOT_PASSWORD}"
      UPLOAD_LIMIT: 50M
      VIRTUAL_HOST: phpmyadmin.example.com
      LETSENCRYPT_HOST: phpmyadmin.example.com
    expose:
      - 8081
    links:
      - db:db

  db:
    image: mysql:latest
    container_name: wordpressdb
    restart: unless-stopped
    command: [
        '--default_authentication_plugin=mysql_native_password',
        '--character-set-server=utf8mb4',
        '--collation-server=utf8mb4_unicode_ci'
    ]
    volumes:
      - ./wp-data:/docker-entrypoint-initdb.d
      - db_data:/var/lib/mysql
    environment:
      MYSQL_DATABASE: "${DB_NAME}"
      MYSQL_ROOT_PASSWORD: "${DB_ROOT_PASSWORD}"
      MYSQL_USER: "${DB_USER_NAME}"
      MYSQL_PASSWORD: "${DB_USER_PASSWORD}"

volumes:
  db_data:

Save the file with Ctrl + X, then Y to confirm.

The configuration pulls WordPress, WP-CLI, phpMyAdmin, and MySQL images, setting them up with necessary environment variables and volumes. It’s tailored for SSL and uses Nginx for serving requests. For further customization options, check the WordPress DockerHub page.

Create the environment variables file:

$ nano .env

Insert the following configuration:

DB_NAME=wordpress
DB_USER_NAME=username
DB_USER_PASSWORD=userpassword
DB_ROOT_PASSWORD=password

Save the file with Ctrl + X, then Y to confirm. Customize the credentials as needed.

Prepare a custom PHP configuration:

$ mkdir config
$ nano config/php.conf.ini

Add this configuration:

file_uploads = On
memory_limit = 500M
upload_max_filesize = 30M
post_max_size = 30M
max_execution_time = 600

Save and close the file.

Step 4 – Update Docker Compose For Nginx

Set up Nginx for WordPress and phpMyAdmin:

Create configuration directories:

$ mkdir nginx
$ mkdir nginx/vhost

Create the Nginx configuration file for WordPress:

$ nano nginx/vhost/wordpress.example.com

Insert the configuration:

server_tokens off;
client_max_body_size 30m;

Save and repeat for phpMyAdmin:

$ nano nginx/vhost/phpmyadmin.example.com

Insert:

server_tokens off;
client_max_body_size 50m;

Open the Docker Compose file:

$ nano docker-compose.yml

Add Nginx service configuration:

  nginx:
    container_name: nginx
    image: nginxproxy/nginx-proxy
    restart: unless-stopped
    ports:
        - 80:80
        - 443:443
    volumes:
        - /var/run/docker.sock:/tmp/docker.sock:ro
        - ./nginx/html:/usr/share/nginx/html
        - ./nginx/certs:/etc/nginx/certs
        - ./nginx/vhost:/etc/nginx/vhost.d
    logging:
        options:
            max-size: "10m"
            max-file: "3"

Save the file.

Step 5 – Update Docker Compose for SSL

Edit the Docker Compose file for SSL setup:

$ nano docker-compose.yml

Add the Acme Companion service:

  acme-companion:
    container_name: acme-companion
    image: nginxproxy/acme-companion
    restart: unless-stopped
    volumes_from:
        - nginx
    volumes:
        - /var/run/docker.sock:/var/run/docker.sock
        - ./nginx/acme:/etc/acme.sh
    environment:
        DEFAULT_EMAIL: certbot@example.com

Save your changes.

Step 6 – Start and Install WordPress

Launch the Docker containers:

$ docker compose up -d

Verify their status:

$ docker ps

Visit https://example.com to start WordPress installation.

WordPress Installer Language Select

Select your language and continue to enter site details. Complete the WordPress installation.

WordPress Installer Site Details

Log in and access the WordPress dashboard.

WordPress Dashboard

Step 7 – Access PhpMyAdmin

Access PhpMyAdmin at https://phpmyadmin.example.com.

phpMyAdmin Login Page

Login with root credentials to manage databases.

phpMyAdmin Dashboard

Step 8 – Access WP-CLI

Check WP-CLI version:

$ docker compose run --rm wpcli cli version

Create an alias for WP-CLI:

$ alias wp="docker compose -f ~/wordpress/docker-compose.yml run --rm wpcli"

Use the alias:

$ wp cli version

Make alias permanent by editing ~/.bashrc:

$ nano ~/.bashrc

Add at the end:

# Custom aliases
alias wp="docker compose -f ~/wordpress/docker-compose.yml run --rm wpcli"

Save and source the file:

$ source ~/.bashrc

Step 9 – Backup WordPress

Navigate to the WordPress directory:

$ cd ~/wordpress

Backup the database:

$ docker compose exec db sh -c "exec mysqldump wordpress -uroot -p" | sudo tee wp-data/data_`date +%d-%m-%Y"_"%H_%M_%S`.sql > /dev/null

List backups:

$ ls -al wp-data

Restore using SQL file or command:

$ docker compose exec db sh -c "exec mysql -uroot -p" < wp-data/data_11-01-2023_10_14_40.sql

Create a daily cron job for backup:

$ sudo nano /etc/cron.daily/wpbackup.sh

Add this script:

#!/bin/bash
docker compose exec db sh -c "exec mysqldump wordpress -uroot -p" | tee wp-data/data_`date +%d-%m-%Y"_"%H_%M_%S`.sql > /dev/null

Make it executable:

$ sudo chmod +x /etc/cron.daily/wpbackup.sh

Step 10 – Upgrade WordPress

Before upgrading, back up the database. Then:

$ cd ~/wordpress

Stop containers:

$ docker compose down --remove-orphans

Pull latest images:

$ docker compose pull

Restart them:

$ docker compose up -d

Conclusion

This concludes our tutorial on installing WordPress using Docker Compose, phpMyAdmin, and WP-CLI. If you have any questions, feel free to post them in the comments below.

Frequently Asked Questions (FAQ)

  • Q: Why use Docker for WordPress installation?A: Docker simplifies deployment with consistent environments, making it easy to scale and replicate the setup across multiple servers.
  • Q: How do I customize the WordPress environment?A: You can customize by modifying the Docker Compose file and associated configurations. Refer to the WordPress DockerHub page for additional options.
  • Q: Is phpMyAdmin mandatory for managing WordPress databases?A: While helpful, phpMyAdmin is not mandatory. You can manage your database directly using MySQL commands in the Docker container.
  • Q: How can I ensure my site is secure?A: Use SSL through Let’s Encrypt as shown, regularly update containers, monitor for vulnerabilities, and use security plugins within WordPress.