How To Enable on (NetBSD)

In NetBSD 2.0 as the package security/pflkm, in the base system from NetBSD 3.0 onwards

Your kernel configuration file needs these non-default options:

pseudo-device  pf		# PF packet filter
pseudo-device  pflog		# PF log interface

Add to /etc/rc.conf:

NetBSD$ sudo modload /usr/lkm/pf.o; 


NetBSD$ sudo pfctl -e

NetBSD$ sudo /etc/rc.d/pf start ; sudo /etc/rc.d/pflogd start

in /etc/lkm.conf:

/usr/lkm/pf.o - - - - BEFORENET

Also see NetBSD PF pages.