How to Set Up WordPress Multisite on Hosting — Step by Step

WordPress Multisite is a hidden gem built into WordPress Core that lets you run multiple websites from a single installation — reducing costs, simplifying management, and saving significantly on hosting. This guide walks you through every step to get it running on AsiaGB Hosting.

What is WordPress Multisite?

WordPress Multisite (formerly WordPress MU / Multi-User) is a system that combines multiple WordPress sites into one shared database and core file set. Each site has its own content, users, and settings while sharing WordPress Core, Themes, and Plugins.

When Should You Use Multisite?

• Multi-language sites — site.com (TH), site-en.com (EN), site-zh.com (ZH)
• Multiple brands in one organization — each brand with its own look
• Schools / Franchises — each branch gets its own sub-site
• Cost reduction — one hosting account instead of many
• One team managing multiple sites — admins work from a single dashboard

Requirements Before You Start

• WordPress 3.0+ (Multisite is built-in)
• PHP 7.4+ (8.1+ recommended)
• Apache mod_rewrite enabled
• Ability to edit wp-config.php and .htaccess
• For Subdomain: Wildcard DNS Record (*.domain.com)
• WordPress installed in the root directory (not a subfolder)
• Deactivate all plugins before enabling Multisite

Step 1 — Enable Multisite

/* Enable WordPress Multisite */
define( 'WP_ALLOW_MULTISITE', true );

Step 2 — Choose Network Type

WordPress Multisite supports two URL structures:

Step 3 — Update wp-config.php and .htaccess

WordPress will display the exact code to add. Example for Subdirectory:

// wp-config.php — add after WP_ALLOW_MULTISITE
define( 'MULTISITE', true );
define( 'SUBDOMAIN_INSTALL', false );
define( 'DOMAIN_CURRENT_SITE', 'example.com' );
define( 'PATH_CURRENT_SITE', '/' );
define( 'SITE_ID_CURRENT_SITE', 1 );
define( 'BLOG_ID_CURRENT_SITE', 1 );

# .htaccess — replace the existing WordPress block
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]

Step 4 — Access Network Admin

After saving both files, log in again. You'll see My Sites → Network Admin in the Admin Bar — your main hub for managing the entire Network.

Step 5 — Create a Subsite

Domain Mapping — Custom Domain per Subsite

To give a subsite its own independent domain (e.g. brand2.com instead of example.com/brand2/):

1. Add an A record for brand2.com pointing to your Hosting IP in DNS
2. Add the domain as Addon Domain in DirectAdmin (Domain Management → Add Domain)
3. Go to Network Admin → Sites → Edit that subsite
4. Change the Site Address (URL) to https://brand2.com
5. Wait for DNS propagation (10–30 minutes)

Managing Plugins and Themes in a Network

Performance Tips for Multisite

• Object Cache — Redis or Memcached significantly reduces database queries
• CDN for Media — offload media to CDN if subsites have many images
• Disable WP-Cron — use Server Cron instead (WP-Cron fires more often in Multisite)
• Limit Upload Size — Network Admin → Network Settings → Max upload file size

Backing Up a Multisite Network

Multisite backups must cover:

• Full database — all subsite tables are in the same database
• wp-content/uploads/sites/ — each subsite's media in separate subdirectories
• wp-config.php — contains critical Network configuration

AsiaGB Hosting provides twice-monthly automated backups (1st and 15th) as a safety net, but we recommend backing up more frequently — especially before WordPress Core updates.

Common Problems and Fixes

Tags: HostingWordPress