pf (OpenBSD Packet Filter)

“Any standard PC with two or more Ethernet interfaces and OpenBSD with PF.”

“There's a couple of cool things coming from OpenBSD camp, most notably OpenSSH and PF.”

“aggressively bring in new security features like pf, OpenSSH”

“Whatever a firewall can do, PF can do it.”

“inventions by OpenBSD team (often using Open as prefix) become standard, such as OpenSSH and PF”

“quality of subset of network drivers and subsystems like pf to support your mission”

“nftables syntax makes me love pf’s syntax even more”

“OpenBSD changed the rules syntax for some reason and the other platforms with pf kept the existing syntax”

“Didn't I just read a few days ago about pf queues just now breaking 4Gbps?”

“it is finally performing acceptably since a couple of years back”

“I also don't really care for how pf specifies rules”

“pf leaves performance on the table”

“it is used widely for its simplicity and reliability”

“PF is intuitive and easy to work with, even for non network gurus.”

“I think their PF now has support for SMP, but maybe it's still in development?”

“PF operates a LOT more like commercial firewalls in how you think about filtering and NAT.”

“Just doing packet filtering doesn't buy you all that much anymore these days”

“I prefer pf, but I don't recommend it to people new to firewalls.”

“has blessed breaking pf multiple times by changing the rule syntax”

“I find it intuitive and even enjoyable to work on.”

“It's slower than nftables.”

“The easiest change to make to pf is making BC breaks to everyone’s firewall config which OpenBSD has done multiple times.”

“It's easy to configure and still human readable, even for more advanced firewall gateway setups”

“That firewall config is just easy to grok, easy to read up on and does 99.999% of what you ever need out of a firewall.”

“Jails, ZFS, pf, bhyve, Dtrace are very well integrated with eachother”

“the miserable single-threaded `pf` on OpenBSD is still”

“the single threaded nature killed it for any serious usage for me”

“I still prefer PF syntax over everything else though”

“I've been using OpenBSD and PF for nearly 25 years (PF debuted December 2001)”

“PF is incredibly intuitive and powerful”

“Personally, I don't really care for PF, but it offers pfsync, which I do care for, so I use it”

“It's just a very capable firewall with a pleasurable configuration language.”

“Once you've gone pf you'll pine for it when working with anything else.”

“adjusting from the reference PF to the minor differences on FreeBSD's version is not too bad.”

“hands down my favorite combination for simple packet filter firewalls”

“pf is easier to read and understand, easier to adjust, more dynamic”

“I prefer pf and the simplicity of OpenBSD over Debian for such a purpose-built application”

“NIC passes the RX buffer directly to the firewall (ipfw, pf, or ipfilter)”

“Playing with jails, pf, ZFS, and some other goodies has been a lot of fun.”

“pretty much the most well regarded firewall there is - with a nice, sensible DSL for config”