If you're using PF instead of IPFW on FreeBSD, for that book yes.
I would actually say maybe/maybe-not for the other book. MWL writes great stuff but the book is sort of specific to OpenBSD (and even a little bit outdated then: sudo vs doas). You could probably get the same out of deep reading of man pages. If you don't know your way around man or BSD init yet, then yes, pick it up.
I would actually say maybe/maybe-not for the other book. MWL writes great stuff but the book is sort of specific to OpenBSD (and even a little bit outdated then: sudo vs doas). You could probably get the same out of deep reading of man pages. If you don't know your way around man or BSD init yet, then yes, pick it up.