Dockerize Your WordPress: A Comprehensive Guide to Hosting WordPress on Docker

Hosting WordPress on Docker is a powerful solution that combines the flexibility of containerization with the robustness of the WordPress platform. Docker allows you to create isolated environments, known as containers, which encapsulate all the necessary components to run WordPress efficiently. In this comprehensive guide, we will explore the step-by-step process of hosting WordPress on Docker, highlighting the benefits it brings in terms of increased performance and enhanced security.

What is Docker

Docker is a container platform that allows developers to easily create, package, and deploy applications in a portable and scalable way. With Docker, applications can be packaged into containers that include all of their dependencies and configuration files. These containers can be deployed and run on any system that supports Docker, making it easy to move applications between environments without the need for manual configuration or setup.

Using Docker offers many advantages over traditional application deployment methods. Docker provides a consistent and isolated runtime environment, which helps to reduce interference and improve security. Docker also makes it easy to scale applications to handle changes in traffic, ensuring optimal performance even during peak periods. Additionally, Docker simplifies the deployment process, making it possible to deploy applications in a matter of minutes rather than hours or days.

Why host WordPress on Docker

Docker is a powerful tool for hosting WordPress instances, and it offers several advantages over traditional hosting methods. By hosting WordPress on Docker, you can easily manage and deploy multiple instances of WordPress, customize and configure your setup to meet your needs, and make updates and changes quickly and easily.

One of the biggest benefits of Docker is the ability to create and manage multiple containers, each with their own instance of WordPress. This makes it easy to manage multiple websites and applications, without having to worry about conflicts or compatibility issues. With Docker, you can easily spin up and down containers, test out new configurations, and experiment with different setups.

Another advantage of hosting WordPress on Docker is that it makes it easy to customize and configure your environment to meet your specific needs. You can easily create your own Docker images, which can contain specific versions of WordPress, along with any plugins, themes, or other dependencies you need. This makes it easy to create and replicate your setup across different environments, ensuring that your website runs smoothly and efficiently.

Finally, Docker makes it easy to make updates and changes to your WordPress setup. With traditional hosting methods, updating your instance of WordPress can be a time-consuming and error-prone process, especially if you have multiple sites and applications running on the same server. With Docker, you can easily update your containers, either manually or through automation tools like Ansible or Puppet, ensuring that your sites are always up-to-date and secure.

ALSO READ – Level Up Your WordPress Development with wp-env

Installing Docker Desktop

To install Docker Desktop on Windows, you need to follow these steps:

1. Go to the Docker website and download the installer for your version of Windows.
2. Click on the downloaded installer to start the installation process.
3. Follow the prompts on the screen to complete the installation. During the installation, you will be asked to choose whether you want to use WSL or Hyper-V backend. You can select either option depending on your needs (although, WSL is recommended)
4. Once the installation is complete, you should see the Docker icon in your system tray.
5. Click on the Docker icon to start Docker Desktop. You can then start using Docker to create and run containers.

Note that Docker requires Windows 10/11 Professional or Enterprise, with WSL/Hyper-V enabled, and 64-bit Windows.

Creating a Docker Compose File for WordPress

To create a Docker Compose file for WordPress, you need to first define the various services that your application requires, including the WordPress image, the MySQL image, and the volumes needed to persist data through hosting. You can also add other services like backup and caching as per your requirements.

Once you have defined the services needed, you can specify environment variables necessary for each service and specify the ports that your application requires. This file will help to simplify the process of deployment and management within a containerized environment.

Docker compose file for WordPress:

services:
  db:
    image: mariadb:latest
    command: '--default-authentication-plugin=mysql_native_password'
    volumes:
      - db_data:/var/lib/mysql
    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=somewordpress
      - MYSQL_DATABASE=wordpress
      - MYSQL_USER=wordpress
      - MYSQL_PASSWORD=wordpress
    expose:
      - 3306
      - 33060
  wordpress:
    image: wordpress:latest
    volumes:
      - wp_data:/var/www/html
    ports:
      - 80:80
    restart: always
    environment:
      - WORDPRESS_DB_HOST=db
      - WORDPRESS_DB_USER=wordpress
      - WORDPRESS_DB_PASSWORD=wordpress
      - WORDPRESS_DB_NAME=wordpress
volumes:
  db_data:
  wp_data:

To launch your WordPress application container using the Docker Compose CLI tool, navigate to the directory with your Compose file in Terminal and enter the command:

docker-compose up -d

This will launch your WordPress application container in the background, and you will be able to manage it easily.

Setting up WordPress

To complete the WordPress setup, you’ll need to visit http://localhost. This is a local address that refers to your own computer. Once you’re there, you should see some instructions on how to complete the setup process. Follow the prompts and enter the necessary information to get your WordPress site up and running.

Enhancing Performance with Caching

Caching is an effective way to speed up your WordPress site. When a page is cached, it means that instead of going through the whole process of generating the page on every request, WordPress just serves up a copy of the page that was created earlier. This can result in significantly faster page load times.

To use caching on your WordPress site, you can use plugins like WP Super Cache or W3 Total Cache. These plugins allow you to configure various caching options to suit the needs of your site.

One of the simplest caching options is page caching. This just caches the final output of a page and serves it up to users without having to regenerate the page. There are also more advanced caching options, like object caching and database caching, which can further speed up your site.

Now, let us look at each of them one by one.

Page Caching

WordPress page caching is an effective way to speed up your website and improve its overall performance. There are many caching plugins available for WordPress, which can help you achieve this goal. Here are some steps to implement page caching using a plugin:

1. Install a caching plugin like WP Super Cache or W3 Total Cache. These plugins are easy to install and configure, and will do most of the work for you.

2. Once you have installed the plugin, go to its settings page and turn on page caching. This will generate static HTML files for your pages, which can then be served to visitors instead of dynamic pages.

3. Configure the caching plugin to work with your website’s setup. This could involve configuring the plugin to work with your theme or with third-party plugins.

4. Test your website to make sure that caching is working properly. Check page load times and make sure that pages are being served from the cache.

Object Caching

Redis object caching is a popular solution to speed up the performance of WordPress sites. It allows WordPress to store database query results, API data, and expensive operations in memory, reducing the need to query the database with each request.

To use Redis object caching, you first need to install and configure Redis on your server. Once Redis is installed, you need to install a Redis object caching plugin for WordPress. Add the following to the docker-compose.yml file (just before the volumes: line) to spin up a redis docker container:

services:
  redis:
      image: 'redis:alpine'
      ports:
        - '6379:6379'
      restart: always
      expose:
        - '6379'

Here are the step-by-step instructions to enable Redis object caching in WordPress:

1. Install Redis on your server: You can use the Redis website’s instructions to install Redis on your server. You can use either the Redis package manager or compile Redis from source.
2. Install the Redis Object Cache plugin: There are several plugins available for using Redis as an object cache for WordPress. One of the most popular ones is Redis Object Cache by Till Krüss. You can install this plugin by going to Plugins > Add New in your WordPress dashboard.
3. Configure Redis Object Cache: Once you have installed the Redis Object Cache plugin, you need to configure it to use your Redis server. Go to Settings > Redis in your WordPress dashboard and enter your Redis server details, such as hostname, port, password, and the prefix for your cache keys.
4. Test Redis Object Cache: To make sure that Redis object caching is working correctly, you can use a plugin like Query Monitor to monitor the number of database queries on your site. With Redis object caching enabled, you should see a significant reduction in the number of database queries.

Enabling SSL/TLS Encryption with Let’s Encrypt

To enable SSL/TLS encryption with Let’s Encrypt on Docker, you can use Certbot and the Docker Compose file.

Here we use image from linuxserver/letsencrypt, which will handle the verification process, and renew the certificate every month.

Since we only have one container to start, follow the instruction from official documentation and simply run it from terminal with the following command:

sudo docker run -d –network=”wordpress_default”\
–cap-add=NET_ADMIN \
–name=letsencrypt \
-v :/config \
-e PGID= -e PUID= \
-e EMAIL= \
-e URL=domain.com \
-e SUBDOMAINS=www \
-e VALIDATION=http \
-p 80:80 -p 443:443 \
-e TZ= \
linuxserver/letsencrypt:196

Troubleshooting

Here are some common troubleshooting steps for running WordPress on Docker:

1. Check the Docker container logs: Run the “docker-compose logs” command to check the container logs and look for any error messages or warnings.

2. Ensure the containers are running: Use the “docker-compose ps” command to check if the containers are running.

3. Verify the network settings: Confirm that the WordPress container is connected to the correct network by running the “docker network inspect” command.

4. Check the database connection: Ensure that the WordPress container is connecting to the correct database by checking the “DB_HOST” environment variable in the docker-compose file.
5. Verify the WordPress configuration: Make sure the appropriate configuration options are set in the WordPress configuration file “wp-config.php”.

6. Review permissions: Check that the file permissions are set correctly for the WordPress files and folders on the host filesystem.

7. Update to the latest image: Update to the latest Docker image for WordPress to ensure any known bugs or issues have been fixed.

8. Restart the containers: Sometimes all that is needed is to restart the containers to resolve issues.

By following these common troubleshooting steps you may be able to isolate the issue and fix it.

Verdict

Running WordPress on Docker can provide numerous benefits such as portability, scalability, and efficient resource utilization. By containerizing your WordPress application, you can deploy it easily across different environments and reduce the risk of conflicts with other applications. Additionally, with Docker, you can easily scale your application horizontally and optimally utilize your server resources. Overall, running WordPress on Docker can offer a streamlined and efficient solution for managing your website or blog.

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