How to restrict the site preview URL for the particular domain alone ?

Solution :

To restrict the site preview URL for the each domain login to the server WHM and go to the path,

Home » Security Center » Apache mod_userdir Tweak

Here you can able to see all hosted domains in your dedicated server. In this there is a column called ” Exclude Protection ” . check the check box for the particular domain to which you want to enable. Hence for that domain alone you can able to check the site preview with the IP address of the server.