First of all you need root login, than you need to install GeoIP for your CentOS server, let me show you how you can do that:
Install Epel repo – Go to https://fedoraproject.org/wiki/EPEL and pick .rpm package for your system, if you have CentOS 6.x you can use epel-release-6-8.noarch.rpm
rpm -i epel-release-6-8.noarch.rpm.
After that you can use yum to install GeoIP –
yum install GeoIP GeoIP-devel
Ok so when you install GeoIP you have to install a custom mod for cpanel.
tar -C /var/cpanel/easy/apache/custom_opt_mods -xzf custom_opt_mod-mod_geoip.tar.gz
And you are done. Next step is to log in to your WHM and go to EasyApache, and pick mod_geoip on your module list, you are all set.