Poor Mans IDS is a couple of scripts which check certain files on your host (any you like) for changes in content, ownership, and mode. Rather than only mailing if something is wrong (like other IDSs), this lean IDS will send you a daily (or weekly or hourly, depending on how you set-up your cron job) security audit, containing details of what it found.
You can download it from the following link: https://packetstormsecurity.com/files/download/29517/pmids-1.5.tar.gz
Source: https://packetstormsecurity.com/files/29517/pmids-1.5.tar.gz.html