I know this has already been explained in other posts and I really don't care. This entry is for me and my sometimes-failing-memory to serve as a reminder when I have to reinstall OSX again in the future.

To start logging IPFW entries, here is an example:

% sudo sysctl -w net.inet.ip.fw.verbose=1

% sudo ipfw add 1 allow log ip from any to any

edit the file /etc/syslog.conf to log to the file of your preference

!-ipfw (at top of file to exclude it from any file

!ipfw *.* /var/log/ipfw.log (at bottom of file to log to ipfw.log file)