How To Enable (FreeBSD)

FreeBSD 8 has ~ OpenBSD 4.1's PF, FreeBSD 9 and newer has ~ OpenBSD 4.5 PF

The FreeBSD Handbook says

/etc/rc.conf

pf_enable="YES"                 # Enable PF (load module if required)
pf_rules="/etc/pf.conf"         # rules definition file for pf
pf_flags=""                     # additional flags for pfctl startup
pflog_enable="YES"              # start pflogd(8)
pflog_logfile="/var/log/pflog"  # where pflogd should store the logfile
pflog_flags=""                  # additional flags for pflogd startup

Fortunately most of these are the defaults (check your /etc/defaults/rc.conf), you need only add

pf_enable="YES"                 # Enable PF (load module if required)
pflog_enable="YES"              # start pflogd(8)

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