An Addon Domain is a feature that allows another domain name to point to a different folder of your hosting account. This means you can host more than one website/domain name from within your cPanel account.
To add an addon domain, login to your cPanel, navigate to Domains ➜ Addon Domains
In the New Domain Name text box, enter the new addon domain’s name. When you enter the domain name, cPanel automatically populates the Subdomain and Document Root text boxes.
Your main cPanel FTP account will of course have access to this Addon domain, but if you want to create a seperate FTP account just for this Addon domain, tick on the box next to “Create an FTP account associated with this Addon Domain.” – Please note: Unless you specifically need an FTP account for the addon domain (i.e., allowing limited access to a developer or similar) we do not recommend creating this FTP account.
Click Add Domain and your Addon domain will be created.
After creation the server will add a request for an AutoSSL certificate to secure the new domain and install it when it becomes available.
If you get the following error ” Sorry, the domain is already pointed to an IP address that does not appear to use DNS servers associated with this server. Please transfer the domain to this servers nameservers or have your administrator add one of its nameservers to /etc/ips.remotedns and make the proper A entries on that remote nameserver. “
For the above error: When creating an Addon domain make sure the DNS servers for the Addon domain are the same as the as DNS servers set for the main domain of the cPanel account you are adding on to.