The fresh 4th edition of The Book of PF in physical form has reached Europe (Ireland), https://www.linkedin.com/posts/tomsmythconnect_thebookofpf-openbsd-packetfilter-activity-7427686906349555713-7s4w - so my stack of author copies are hopefully on the way too.
The book home page is at https://nostarch.com/book-of-pf-4th-edition
Some background https://nxdomain.no/~peter/yes_the_book_of_pf_4th_ed_is_coming.html @nostarch #bookofpf #openbsd #freebsd #pf #packetfilter #networking #security