In order to park a domain on top of an addon domain, please do the following:
- Login to cPanel and click Addon Domains
- In the field to the right of "New Domain Name", type the domain name you wish to park on top of your addon domain
- Click outside the text box and your other settings will populate.
- Under "Document Root:", erase everything except "public_html"
- Look down to your current addon domain and its "Document Root"
- Take the "Document Root" and insert it in the field to the right of "Document Root:" at the top.
- Insert any password in the password field. (You won't need to remember this password, so just use the Generate Password button.)
- Click Add Domain!
You have now just parked a domain onto of an addon domain.