This post documents how I configured software on systems I administer. I like to run OSSEC on servers as a means to monitor and analyze log files. I wanted something simple so I installed a program to brute force SSH on 172.16.2.1.1 (r200a) The next step is to configure OSSec to tell the server to block the offending source IP for a period of time. The result is that the IP address is blocked for 600 seconds or 10 minutes.”]
Source: https://taosecurity.blogspot.com/2008/12/ossec-and-pf-on-freebsd-to-limit-ssh.html