Presentation

PF, The OpenBSD Packet Filter: Building The Network You Need, EuroBSDCon 2015, Stockholm, Sweden, October 1st 2015

Tutorials & HowTos

Pf Firewall “how to” – FreeBSD and OpenBSD ( pf.conf )
Paket Filter (PF) von OpenBSD und ALTQ
Getting AltQ working in pf.conf (limiting inbound Tor traffic)
PF Firewall Quick Guide
FreeBSD Tuning and Optimization – performance modifications for 1gig and 10gig networks

Statistics

pfstat
ALTQ statistics?

ntop (Official)
ntopng – High-Speed Web-based Traffic Analysis and Flow Collection (Official)
ntop (Wikipedia)
NTop
Network Monitoring Using Free Linux Tools
Unveiling Application Visibility in ntop and nProbe (both in NetFlow v9 and IPFIX)

FAQ

Table not found

Couldn't manipulate device /dev/pf: No such process

table <hacker> persist {
}

$ pfctl -n -f /etc/pf.conf       # Parse the configuration file, do not actually load rules
$ pfctl -T load -f /etc/pf.conf  # Load only the table definitions
$ pfctl -t hacker -T show        # Show the content of a table