How to Set Up Multisite in Drupal

Drupal is a powerful content management system (CMS) that allows organizations to manage a wide range of websites. One of the most useful features in Drupal is its multisite capability, which enables you to host multiple websites on a single Drupal installation. This can be especially beneficial for managing different websites under one domain or managing various regional websites for a global organization. Setting up a Drupal multisite environment requires careful planning and configuration, particularly when considering server resources, hosting, and colocation options. Below is a step-by-step guide on how to set up a multisite in Drupal.

Ensure System Requirements and Environment Setup

Before beginning the process of setting up a multisite in Drupal, it’s essential to verify that your server and hosting environment meet the requirements for running Drupal. Multisite setups require a robust server configuration that can handle multiple sites simultaneously.

Server Configuration: Ensure your server is capable of running multiple websites. The server should have sufficient resources (CPU, RAM, and disk space) to handle the additional load from multiple Drupal sites. Colocation hosting can be beneficial in this case, as it allows you to house your server in a dedicated, professionally managed facility, offering reliable performance and security.

Database: Multisite setups in Drupal typically use a single database for all sites. This means your database should be optimized for handling multiple sets of data and should be configured with sufficient resources to ensure fast performance.

Drupal Installation: Ensure that your Drupal installation is up to date. You need to install the Drupal core files on your server, which will act as the base for all of the sites in your multisite environment.

Prepare the File System

In a multisite setup, each site shares a common Drupal codebase, but their content and configuration are stored in separate directories. You will need to configure your file system appropriately.

Create Site-Specific Directories: In your Drupal installation, navigate to the sites directory. Inside sites, create a subdirectory for each website you want to host. For example, if you are setting up two websites, site1 and site2, your structure should look like this:
/sites

    /site1

    /site2

Each subdirectory will store its own configuration files and will point to a shared Drupal installation.

Set Up Domain and Database Configuration

For each site in your multisite environment, you will need to configure unique database settings and specify the domain names that will point to each individual site.

Configure Database Settings: Multisite setups allow you to use a single database for multiple sites. Each site will be assigned its own prefix in the database. You will need to configure the settings.php file for each site under its respective directory. This file contains all the necessary configuration to link the site to the correct database table prefix and settings.
Example for site1/settings.php:
$databases['default']['default'] = array (

  'database' => 'your_database_name',

  'username' => 'your_database_user',

  'password' => 'your_database_password',

  'host' => 'localhost',

  'prefix' => 'site1_',

);

Set Up Domain Names: Each site needs to be accessible via its own domain name or subdomain. Update your server’s DNS settings to ensure the correct domains or subdomains are pointed to your Drupal installation. For example, site1.example.com should point to the sites/site1 directory, and site2.example.com should point to the sites/site2 directory.

Adjust File Permissions and Configure File System Paths

Each site within a multisite environment may need to have its own file upload directories, such as for images or documents. These directories should be set up with proper file permissions to allow Drupal to upload and manage media content.

File Permissions: Ensure that the file directories for each site have the correct read/write permissions. If you are using colocation hosting, ensure your server has appropriate access and permissions set for file management.
Example:
/sites/site1/files

/sites/site2/files

Set these directories with appropriate ownership and permissions for Drupal to manage the content.

Configure the Settings for Each Site

Once the basic file system setup is done, you need to configure specific settings for each site.

Configure Settings.php: In addition to database configuration, the settings.php file also controls file paths, caching settings, and other configurations for each site. Each site’s settings.php will have settings specific to that site while sharing the common Drupal codebase.

Install Modules and Themes: Since all the sites in a multisite environment share the same codebase, any modules or themes you want to use must be installed in the main sites/all/modules or sites/all/themes directory. If you need site-specific modules or themes, you can place them in the sites/[sitename]/modules or sites/[sitename]/themes directory.

Test the Setup

Once you have configured the necessary files and settings for each site, it’s time to test your multisite setup. Clear the Drupal cache, navigate to each site’s URL, and ensure that everything is functioning as expected. Verify that the databases are correctly set up, and that content and configuration are isolated for each site.

Monitor and Maintain the Multisite Environment

Once your multisite setup is live, it’s important to monitor server performance and resource allocation, particularly in a shared hosting or colocation environment. Use tools to track server load, database performance, and website uptime. Regular maintenance tasks such as updating Drupal core, themes, and modules should be done across all sites, but be cautious not to disrupt the functionality of any individual site.

Conclusion

Setting up a multisite environment in Drupal is a great way to efficiently manage multiple websites with a shared infrastructure. By following the steps outlined above, you can configure your Drupal installation, server, and hosting setup to handle multiple sites. Properly managing file system paths, domain configurations, and database settings is essential to ensure that your multisite environment functions smoothly. Additionally, using colocation hosting can help you ensure that your server infrastructure is reliable and secure, giving you the control and resources needed to manage your multisite Drupal setup effectively.