Introduction
Mod_evasive is an Apache module that can help mitigate some DOS and DDOS attacks on the Apache webserver.
Procedure
cPanel provides the Apache module mod_evasive that you can install using yum or the Easy Apache 4 interface:
ea-apache24-mod_evasive
Mod_evasive keeps track of how many times an IP address requests a resource on your sites, if someone makes too many requests a 403 error will return.
Mod_evasive will log the offending IP address to file in the following location:
/var/log/apache2/mod_evasive/