Change of Multisite Domain - enable Cloudflare on Siteground

Issue

A surge of connection to the shared server has caused Siteground to restrict access to the site hosted. As they suspect it was a DOS attack (Denial of Service attack) or the Slashdot effect. Cloudflare was required to enable in order to lift the restriction.

However, after Cloudflare was enabled and Siteground have lift the restriction, The Network Admin was end up in a redirection loop, while the primary site was functioning in anyway.

Domain Change

The issue was caused by the domain change to use sub-domain www to replace the existing domain. While WordPress Multisite has been in additional Database tables and fields that requires to be update during the process, siteground did not handle it properly.

Solution

Follow the standard procedure of domain change on Multisite WordPress to identify which domain update was missing.

In this case

wp-config.php

define('DOMAIN_CURRENT_SITE', '<newdomain>');

wp_blogs

domain: newdomain

wp_options

siteurl: https://newdomain

wp_site

domain: newdomain

wp_sitemate

siteurl: https://newdomain

Checklist of Changing Domain

Redirect from origin to the new domain

.htaccess

RewriteEngine On
RewriteCond %{HTTP_HOST} ^origin.com [NC]
RewriteRule ^(.*)$ https://newdomain/$1 [L,R=301]

Change URL on Database

Search and Replace

replace all instance of origin domain with the new domain