I was looking for easy to follow mod_security ruleset setup instructions for a cPanel server and found the following website: http://www.ukhost4u.com/blog/248/configuring-modsecurity-with-atomicorp-free-rule-sets/
I have a WHM/Cpanel server with CSF/LFD installed and mod_security enabled.
I used to login to WHM/cpanel from one of my local windows box through a linux (Centos 5)NAT gateway(with a public IP address) . On one day CSF/LFD on the server blocked my gateway from accessing it.
Currently I'm looking into implementing mod_security on all our apache servers. The installation on CentOS 5.5 comes directly with the
"Core Rule Set" by the mod_security devs (curiously Debian and Ubuntu do not carry these)
They also offer the Enhanced Rule Set for mod_security in a commercial package