OSSEC is an Open Source Host-based Intrusion Detection System that performs log analysis, file integrity checking, policy monitoring, rootkit detection, real-time alerting and active response.
There are a couple broken links that I cannot find the right replacement link for (or I would have included them in #1974), but are broken. These include
There are a couple broken links that I cannot find the right replacement link for (or I would have included them in #1974), but are broken. These include