WHM/cPanel + ConfigServer Services
ConfigServer Services offers some great add-on products for cPanel/WHM. http://www.configserver.com/cp/cpanel.html
An awesome firewall program is ConfigServer Security & Firewall or CSF/LFD. NOTE: I'm using cPanel/WHM on CentOS or RedHat Enterprise 64 bit v3 to v6 operating system
1. Download csf.tgz to your root "/" folder
# wget http://www.configserver.com/free/csf.tgz
2. Untar the Distribution:
# tar -xzf csf.tgz
3. Go to the csf/ directory
# cd csf/
4. Once in the csf directory, Install ConfigServer Security & Firewall
# ./install.sh
If running WHM/cPanel then reload WHM if logged in.
Now another great ConfigServer Service is ConfigServer ModSecurity Control (cmc) I use this a lot. It is great for seeing threats/intrusions.
Follow the same directions as above except the download and file names are different.
Link: http://www.configserver.com/free/cmc.tgz
Directory: cmc/
Deleting the csf and cmc folders after installation is fine. ConfigServer Services also has Mail