Ossec
From Atomicorp Wiki
Overview
OSSEC is a host based intrusion detection system, it performs numerous local security controls including log analysis, active-response to attacks (shunning), rootkit detection, file integrity checks, and local security policy assessments. Just to name a few. You can read more about OSSEC here: http://www.ossec.net
Troubleshooting
Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)
This is a known problem in versions of OSSEC 1.6.1 and lower. Currently to fix this an upgrade to a newer version is required:
Step 1) Upgrade to a CVS snapshot (1.99 or higher)
yum --enablerepo=asl-2.0-testing upgrade ossec-hids
Step 2) Update ASL policy
asl -s -f
Step 3) Drop the existing tortix database
mysql -u admin -p`cat /etc/psa/.psa.shadow` drop database tortix
Step 4) Create a new database, and select it
create database tortix; use database tortix;
Step 5) Create the new OSSEC database
mysql -u admin -p`cat /etc/psa/.psa.shadow` tortix < /var/ossec/etc/mysql/mysql.schema
Step 6) restart ossec
/etc/init.d/ossec-hids restart