HowtoForge published a guide about securing CentOS with Bastille

This article shows how to secure a CentOS server using psad, Bastille, and some other tweaks. psad is a tool that helps detect port scans and other suspicious traffic, and the Bastille hardening program locks down an operating system, proactively configuring the system for increased security and decreasing its susceptibility to compromise.

Securing the CentOS Perfect Setup with Bastille