Pf Program Version - Pf Configuration Incompatible With
Older configurations might attempt to skip interfaces using names that are now reserved or formatted differently. While less common, the introduction of interface groups has changed how set skip on lo is interpreted, leading to parser confusion if the interface does not exist or the syntax is malformed according to the new parser rules.
man -s 5 pf.conf # on the target system
Once resolved, take these preventative measures: pf configuration incompatible with pf program version
Ensure your entire base system is at the same release level. For example, on FreeBSD, check your version with freebsd-version -k (kernel) and freebsd-version -u (userland). Older configurations might attempt to skip interfaces using