This is not a decision to be taken lightly, keep in mind that IP addresses can change from time to time and as such you could inadvertently ban a valuable user or even customer form accessing your services. Another thing to be careful about is to ensure you don’t ban a full sub set of IPs which could result in a full network being banned, that said, you could be gaining a lot of spam from a certain country and might wish to ban them geographically.

Right, first of all log into your cPanel with your username and password. Then scroll down to the security section

cPanel Security Options

Click on the IP Deny Manager, you will then be presented with another screen:

cPanel IP Deny Manager

This screen is pretty much self explanatory, pop the IP address of full domain name in the field and click add. You can also remove items at a later date should you require. As you can see your also able to edit IP ranges from and to, but as noted above caution should be used to ensure you don’t ban a full range of IP addresses which lead to you losing users and customers.