What is an addon domain in cPanel

Why is an addon domain connected to a subdomain?

When adding an add-on domain, the corresponding subdomain is created e.g. addon.maindomain.Ending.

In terms of Apache VirtualHost entries, an AddonDomain is a parked domain on this subdomain. There is currently no way to add an AddonDomain without creating a subdomain.
This is the basic principle of the cPanel architecture.
However, it is a common wish not to make the subdomain available.

There are two ways to do this.

1. Redirect both links to a page that was not found using a .htaccess that should be stored in the DocumentRoot / web root directory of the add-on domain:

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond% {HTTP_HOST}
RewriteRule ^ (. *) $ "Http: //
maindomain.Ending/ 404 "[R = 301, L]

2. Point the subdomain addon.maindomain.com and www.addon.maindomain.com to a non-working IP address, e.g. B. localhost (loopback address)
This can be done in the following way in your control panel / cPanel:

a) Go to "DNS Settings" in the Domains section of the control panel.
b) Click on "manage" to the right of the main domain.
c) Next to your addon.hauptdomain.Endung / www.addon.hauptdomain.Endung entry click on "Edit" and enter as the value.