The Book of PF: A No-Nonsense Guide to the OpenBSD Firewall
Publisher: No Starch Press 2010 | 216 Pages | ISBN: 159327274X | PDF | 6 MB
OpenBSD's stateful packet filter, PF, is the heart of the OpenBSD firewall and a necessity for any admin working in a BSD environment. With a little effort and this book, you'll gain the insight needed to unlock PF's full potential.