These links provide details around securing Linux:
http://www.sysadminwiki.net/wiki/index.php?title=Red_Hat_Hardening_Guide
http://wiki.centos.org/HowTos/OS_Protection
http://www.cyberciti.biz/tips/linux-unix-bsd-nginx-webserver-security.html
http://wiki.eri.ucsb.edu/sysadm/SELinux
Log Processing
- Clearcutter – a tool for processing unfamiliar log files and samples
- Identify specific log messages present in a file
- Identify sequences of log entries that describe an activity thread’
- Test OSSIM plugins against log samples and produce validated Regexes
- Profile regexes for performance against each other and real logs
IP Reputation Database
http://labs.alienvault.com/labs/index.php/projects/open-source-ip-reputation-portal/download-ip-reputation-database/