Moving from OpenBSD to FreeBSD for firewalls

https://utcc.utoronto.ca/~cks/space/blog/sysadmin/OpenBSDToFreeBSDMove

by zdw • 8 months ago

202 146 8 months ago

utcc.utoronto.ca

0xWTF• 8 months ago

I don't understand why this has 29 points and no comments. What's so amazing about this?

wslh2• 8 months ago

Discussion threads about performance?

porker• 8 months ago

It's actually about computers unlike many of the threads today on HN?

wslh2• 8 months ago

I imagine a near future where TCP/IP stacks, and device drivers are interchangeable between operating systems. In Linux, NDISWrapper [1] enables to use Windows drivers in Linux but it's a wrapper (with all due respect to this project).

[1] https://en.wikipedia.org/wiki/NDISwrapper

awesome_dude2• 8 months ago

Microsoft started out with BSD's TCP/IP stack, but dropped it for their own (back in Windows 3.5 apparently - https://news.ycombinator.com/item?id=41495551)

EvanAnderson• 8 months ago

Adam Barr, formerly with Microsoft, goes into some detail about it here: https://web.archive.org/web/20051114154320/http://www.kuro5h...

zokier• 8 months ago

You mean like DPDK?

shanemhansen• 8 months ago

I'd think something like Rump Kernel's is a closer analogue: https://en.wikipedia.org/wiki/Rump_kernel

miladyincontrol• 8 months ago

Sorta, but only with ancient windows XP drivers. It was a useful stopgap of it's era but linux networking drivers have more than caught up in the meantime.

jmclnx• 8 months ago

For me, the only drawback for corporations is the 6 month upgrade. There is no LTS on OpenBSD.

I use OpenBSD as a workstation and it works great, but in a production environment I doubt I would use OpenBSD for critical items, mainly because no LTS.

It is a sad state of affairs because Companies do not want nor will want a system you need to upgrade so often even if its security very good.

rootnod32• 8 months ago

On the other hand though, updates on OpenBSD are the most painless updates I have ever done. I am more concerned about it's usage of UFS instead of something more robust for drives.

kstrauser2• 8 months ago

I'm grossly generalizing here, but it seems like OpenBSD boxes seem to be commonly used for the sorts of things that don't write a lot of data to local drives, except maybe logfiles. You can obviously use it for fileservers and such but I don't recall ever seeing that in the wild. So in that situation, UFS is fine.

(IMO it's fine for heavier-write cases, too. It's just especially alright for the common deployment case where it's practically read-only anyway.)

traceroute662• 8 months ago

updates on OpenBSD are the most painless updates I have ever done

I see we have a post-syspatch (6.1 - 2017), post-sysupgrade (6.6 - 2019) OpenBSD user in our midsts. ;D

You are positively a newbie in the OpenBSD world !

Some of us are old enough to remember when OpenBSD updates were a complete pain in the ass in involving downloading shit to /usr/src and compiling it yourself !

SoftTalker6• 8 months ago

Yet companies insist on enabling unattended upgrades at least for "security" patches, which have introduced breakage or even their own vulnerabilities in the past (Crowdstrike was a recent dramatic example).

OpenBSD will just tell you that maintaining an LTS release is not one of their goals and if that's what you need you'll be better served by running another OS.

rbc• 8 months ago

I think it depends on your needs. Working corporate environments with 1000+ hosts, LTS operating systems are big help. On the other hand, for smaller cases, call it a work group or smaller, I think OpenBSD provides a base system that doesn't typically make drastic changes, along with a ports collection that does a pretty good job of keeping up with the third party applications. It's a good balance. I've recently seen some "Immutable" Linux distributions that are basically spins of upstream distributions. They leave the inherited distribution mostly alone and load the extras using Flatpak or the like. Sounds similar to BSD ports in a way.

trashb• 8 months ago

ok, just don't upgrade it, the focus is security by default anyway there are a lot of openbsd boxes online with a huge uptime running older versions.

throw0101c6• 8 months ago

For me, the only drawback for corporations is the 6 month upgrade. There is no LTS on OpenBSD.

One of the reasons the OP is moving to FreeBSD: five-year support cycles for the major release branches.

* https://www.freebsd.org/security/#sup

awesome_dude2• 8 months ago

There are some things about FreeBSD that we're not entirely enthused about.

Damn I wish that they had expanded on this a bit (not to start a flame war, but to give readers a fuller picture, or even to prod the FreeBSD community into "fixing" those things)

edit: typo fix

lloydatkinson• 8 months ago

It does seem like a weird omission doesn’t it?

cperciva• 8 months ago

One issue, as they point out, is that we now do minor version updates every 6 months, and you need to update for each one. (We have a 3-4 month period where both are supported, but e.g. 15.0 will be EoL before 15.2 is released.)

We are aware that this isn't ideal for some users, but it was a necessary tradeoff. We might be able to improve this in the future (possibly as "security updates for the base system, but no ports support") but no guarantees.

SoftTalker6• 8 months ago

As noted, recent changes to OpenBSD TCP handling[1] may improve performance.

On a 4 core machine I see between 12% to 22% improvement with 10 parallel TCP streams. When testing only with a single TCP stream, throughput increases between 38% to 100%.

I'm not sure that directly translates to better pf performance, and four cores is hardly remarkable these days but might be typical on a small low-power router?

Would be interesting if someone had a recent benchmark comparison of OpenBSD 7.8 PF vs. FreeBSD's latest.

[1] https://undeadly.org/cgi?action=article;sid=20250508122430

wahern2• 8 months ago

That particular change improves throughput received locally. Though over the past few years there's been a ton of work on unlocking the network layer generally to support more parallelism.

For a firewall I guess the critical question is the degree of parallelism supported by OpenBSD's PF stack, especially as it relates to common features like connection statefulness, NAT, etc.

SoftTalker6• 8 months ago

Thanks. Yes after I posted that I started wondering if it was really relevant to pf.

throwaway270925• 8 months ago

Can confirm. Lots of performance improvements lately in OpenBSD. Our Load Balancers basically doubled throughput after updating from 7.6 to 7.7

dylan604• 8 months ago

I once wrote a similar post to an DVD industry centric mailing list (remember those?) regarding switching to FCP7 from Adobe Premiere with a huge difference in how FCP7 would allow capturing of discrete audio channels vs Premiere forcing an interleaved audio stream. Eventually, a rep from Adobe contacted me through my company's PR team (a first for me) to go over the list of complaints. At the end, he agreed these were all valid complaints, and then asked "if Premiere added these changes would I be willing to switch back"? At that point, I said probably not as we'd now be fully switched to FCP7 in all departments. So I understand that sentiment as well. Honestly, I was shocked that someone actually read my missive and actually paid any mind to it. So maybe someone at OpenBSD will be as receptive if not equally unable to do anything about it.

CodeCompost• 8 months ago

The OpenBSD community does not operate like that. It's expected that you fix it yourself.

yuvadam2• 8 months ago

What's wrong with Linux for firewalls? Either openwrt, or any distro really.

Why would any BSD perform better?

(edit: genuinely curious why BSDs are such popular firewalls)

2trill2spill• 8 months ago

I assume in this case they already had a bunch of firewall rules for PF and switching from OpenBSD -> FreeBSD is a much easier lift then going to linux because both the BSDs are using PF, although IIRC there are some differences between both implementations.

electric_mayhem• 8 months ago

PF is really nice. (Source: me. Cissp and a couple decades of professional experience with open source and proprietary firewalls).

And if they are already using it on openbsd, it’s almost certainly an easier lift to move from one BSD PF implementation to another versus migrating everything to Linux and iptables.

theideaofcoffee2• 8 months ago

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

nesarkvechnep2• 8 months ago

What's wrong with using any BSD? Can't people use whatever suits their needs?

yuvadam2• 8 months ago

Of course, I'm genuinely curious why BSDs are more popular as firewalls.

rfmoz• 8 months ago

Let me extend the question to what’s wrong with NFTables on Linux? It’s a different way to manage Netfilter, out of IPTables

guerby• 8 months ago

We migrated to a linux nftables based firewall.

I never liked iptables, but nftables is pretty nice to write and use.

And with one "flowtable" line added to your nftables.conf you can even in theory have faster routing when conntrack is active

https://thermalcircle.de/doku.php?id=blog:linux:flowtables_1...

mikey_p• 8 months ago

Because of PF or Packet Filter (the PF in pfSense FWIW): https://en.wikipedia.org/wiki/PF_(firewall)

wasting_time• 8 months ago

  Compared to working with iptables, PF is like this haiku:

  A breath of fresh air,
  floating on white rose petals,
  eating strawberries.

  Now I'm getting carried away:

  Hartmeier codes now,
  Henning knows not why it fails,
  fails only for n00b.

  Tables load my lists,
  tarpit for the asshole spammer,
  death to his mail store.

  CARP due to Cisco,
  redundant blessed packets,
  licensed free for me.

(From https://marc.info/?l=openbsd-pf&m=108507584013046&w=2 )

Nftables has improved the situation on Linux somewhat, but PF is incredibly intuitive and powerful. A league of its own when it comes to firewalling.

justaboutanyone• 8 months ago

Has there ever been an effort to port PF over to linux, or to create an adaption layer that makes things compatible?

NewJazz• 8 months ago

Nftables is alright IME

waynesonfire• 8 months ago

Uhh... no idea but yea. Its that much better that it deserves a poem.

mrpippy• 8 months ago

One thing I like about using OpenBSD for my home router is almost all the necessary daemons being developed and included with the OS. DHCPv4 server/client, DHCPv6 client, IPv6 RA server, NTP, and of course SSH are all impeccably documented, use consistent config file formats/command-line arg styles, and are privilege-separated with pledge.

jrumbut• 8 months ago

Also it's a really well trodden path. You aren't likely to run into an OpenBSD firewall problem that hasn't been seen before.

Regarding any BSD used for any purpose, BSD has a more consistent logic to how everything works. That said, if you're used to Linux then you're going to be annoyed that everything is very slightly different. I am always glad that multiple BSD projects have survived and still have some real users, I think that's good for computing in general.

mshroyer• 8 months ago

The recent addition of dhcp6leased is a great example: Built into the base system, simpler to configure than either dhcp6c or dhcpcd, and presumably also more secure than either.

INTPenis2• 8 months ago

I've used both and the main advantage is PF/ipfw syntax.

But now with nftables I actually am going back to RHEL on Firewalls. I want something ultra-stable and long lived.

wahern2• 8 months ago

I've been using OpenBSD and PF for nearly 25 years (PF debuted December 2001). Over those years there have been syntax changes to pf.conf, but the most disruptive were early on, and I can't remember the last syntax change that effected my configs (mostly NAT, spamd, and connection rate limiting).

During that time the firewall tool du jour on Linux was ipchains, then iptables, and now nftables, and there have been at least some incompatible changes within the lifespan of each tool.

OpenBSD has an additional leg up in that incompatible changes between releases are concisely, clearly, and consistently documented, e.g. https://www.openbsd.org/faq/upgrade78.html The last incompatible pf.conf syntax change I could find was for 6.9, nearly 5 years ago, https://www.openbsd.org/faq/upgrade69.html

jrmg• 8 months ago

One thing unexpected I found when setting up an OpenBSD based router recently: the web isn’t riddled with low-quality and often wrong SEO and AI slop about OpenBSD like it is for Linux. I guess there just isn’t enough money to be made producing it for it for such a niche audience.

If you search up a problem, you get real documentation, real technical blog posts, and real forum posts with actual useful conversations happening.

lmm3• 8 months ago

Too many random changes, too fiddly to maintain, too much general flakiness. Especially for simple single-purpose devices that you want to set up once and leave alone for years, BSD is generally much nicer than Linux. I'd actually flip your question: why would you ever use Linux rather than FreeBSD?

treesknees• 8 months ago

Do you have any specific examples where a Linux-based firewall was too "random" or "fiddly" or "flaky"? Or provide examples of ways that BSD "much nicer"?

It sounds to me like you picked a bad Linux distro for your use case.

I've seen plenty of single-purpose Linux-based network appliances, and none of them have come across as flaky or unreliable because of the OS. In fact they can be easier to use for people who have more operational experience using Linux already.

linsomniac• 8 months ago

I'm pretty die-hard Linux, but I had a client who needed to do traffic shaping on hundreds or thousands of this ISPs users. I've tried multiple times to get anything more than the most simple traffic shaping working under Linux, with pretty bad luck at it. I set them up with a FreeBSD box and the shaping config, IIRC, was a one-liner and just worked, I never heard any complaints about it.

I've run a lot of Linux firewalls over the decades, but FreeBSDs shaping is <chefs kiss>

candl• 8 months ago

What features have you used for shaping with pf/FreeBSD? I remember (around 8ish years ago) using dummynet with pf, but it wasn't supported out of the box and I used some patches from the mailing lists for this purpose. It wasn't perfect, at times buggy. Back then ipfw had better support for such features, but I didn't like the syntax just as much as iptables. I eventually settled on Linux as I have grown to understand iptables (I hate that nftables is the brand new thing with entirely different syntax to learn again... and even requires more work upfront because basic chains are not preconfigured...) but traffic shaping sucked big time on linux, I never understood the tc tool to be effective, it's just too arcane. I always admired pf, especially on OpenBSD since it had more features but the single threaded nature killed it for any serious usage for me.

TuxPowered• 8 months ago

I did traffic shaping per user for a few hundred users on 1GHz Pentium III on Linux. It can be done just fine.

hapless5• 8 months ago

The user interface is literally 1000x better. That's all

Linux is enormously higher performance but it is a huge pain in the ass to squeeze the performance out AND retain any level of readability

which is why there are like a dozen vendors selling various solutions that quietly compile their proprietary filter definitions to bpf for use natively in the kernel netfilter code...

theideaofcoffee2• 8 months ago

Just more navel-gazing from UTCC. I still don't understand why all of these submissions get upvoted so often. 10G performance just really isn't that interesting anymore, maybe around 2005 when it was the new kid on the block. If they were talking about squeezing firewall performance out of a box with a couple of 200g or 400g adapters and on run-of-the-mill CPUs and no offloading or something like Netflix publishes with their BSD work, I'd be more interested.

cyberpunk2• 8 months ago

It reads a bit like someone LARP'ing a sysadmin. Perhaps they're students or something.

yepguy• 8 months ago

Nah, Chris is definitely a real sysadmin and his blog has been pretty popular in this space for a long time.

kalleboo2• 8 months ago

Despite 10G being far from new it seems like somehow they're still not even achieving that with FreeBSD. Would be more interesting to see an upgrade to Linux.

j45• 8 months ago

I just like the reference to 10G ethernet. It can't become normal soon enough.

kalleboo2• 8 months ago

It's ironic because I chose Linux over FreeBSD due to 10G performance. Be it a TrueNAS box with dual Xeons and Marvell 10G card or a ThinkCentre Tiny with an Intel NIC running opnSense I could never get anywhere near full 10G throughput. Switch to Linux (TrueNAS SCALE/openWrt) and it just worked at full speed.

Although the article also uses weasel words like "sufficiently good" performance so it sounds like their BSD 10G performance isn't that good either.

thatcks3• 8 months ago

I can't remember the 10G firewall figures we got in testing off the top of my head, but we didn't max out the 10G network; I think we were getting somewhere in the 8G range. This is significantly better than our OpenBSD performance but not quite up to the level of full network speed or the full speed that two Linux machines can get talking directly to each other over our 10G network. I also suspect that performance depends on which specific NICs you have due to driver issues. The live performance of our deployed FreeBSD firewalls is harder to assess because people here don't push the network that hard very often (although every so often someone downloads a big thing from the right Internet source to get really good rates).

(I'm the author of the linked-to article.)

Y_Y• 8 months ago

So you don't like OpenBSD, but you do like Ubuntu?

This person seems like they know wht they are talking about and given it serious thought, but I cannot fathom how you could make such a conclusion today.

toast02• 8 months ago

If they're concerned about performance, yeah. OpenBSD doesn't do the basics that you need to get the most out of your SMP hardware; there's no way to set cpu affinity at least from userland, and it's clear that this sort of work is not a priority for OpenBSD; it's not easy work, but FreeBSD has done it. Beyond CPU affinity, you also need your network structures setup to reduce lock contention, things like fine grained locks, hashed subtables and/or "lockless" tables, configuring the NICs as close as possible to one queue per core and keeping flows on the same queue which is pinned to a single core so that the per flow locks never contend and don't bounce between cores.

Ubuntu/Linux do have reasonable performance, but I think they prefer PF firewalls, so that makes Linux a non-option for firewalls.

Personally, I don't really care for PF, but it offers pfsync, which I do care for, so I use it and ipfw... but I need to check in, I think FreeBSD PF may have added the hooks I use ipfw for (bandwidth limits/shaping/queue discipline).

csmpltn• 8 months ago

"there's no way to set cpu affinity at least from userland"

How is that even possible. What's the excuse?

On Windows, setting process affinity has been around since the Windows NT days.

seanw444• 8 months ago

It's not necessarily that OpenBSD can't implement the basics, it's that they don't want to. A lot of the high-performance features introduce potential security vulnerabilities. Their main focus is security and correctness. Not speed.

EliteGadget4• 8 months ago

It appears they have different requirements for those machines. They state the Ubuntu machines are for non-firewall applications. Ubuntu and Debian can configured relatively easily for a number of workstation and server roles.

Also many IT professionals that have used Linux will be familiar with a Debian or a Debian derivative such as Ubuntu. That simply isn't the case with OpenBSD.

I recently installed OpenBSD on my old laptop to try it out and I found it difficult even though I used to use it at University back in the late 2000s.

raddan• 8 months ago

Amusingly, I started using OpenBSD in 2000 because after repeatedly trying to get Debian running on my PowerPC G4 and failing (for months), I discovered that OpenBSD had a PowerPC port that immediately worked. Honestly the hardest part about OpenBSD is the installer, which has a few small improvements over the one back in 2000, but is essentially the same. I'm sure that kids these days will turn to ChatGPT for help, but I learned most of what I knew about hacking on a UNIX machine from OpenBSD's amazingly good man pages; they are still great.

I went through the process again just this weekend, because the disk in my firewall died. It's obvious that they continue to put a lot of effort into the OS. It's too bad that I can't use it as my daily driver, because I gladly would.

stackghost• 8 months ago

It's actually pretty shocking how poorly and sluggish OpenBSD performs, and it's not meaningfully more secure than a properly-configured Linux or freebsd box.

I'm honestly not sure what its use case is in 2025, beyond as a research OS.

fransje26• 8 months ago

but I cannot fathom how you could make such a conclusion today.

https://utcc.utoronto.ca/~cks/space/blog/sysadmin/UsingBindN...

ThinkBeat• 8 months ago

I find it a bit odd that they seem to have gone from having OpenBSD as the standard and are not moving to FreeBSD and Ubuntu.

I an not sure what role these computers that may transition to Ubuntu do, there are probably good reasons, I wish he had expanded on it.

thatcks3• 8 months ago

The computers that moved from OpenBSD to Ubuntu were our local resolving DNS servers. These don't use PF and we also wanted to switch from our previous OpenBSD setup to Bind, where we were already running Bind on Ubuntu for our DNS master servers. The gory details were written up here: https://utcc.utoronto.ca/~cks/space/blog/sysadmin/UsingBindN...

We may at some point switch our remaining OpenBSD DHCP server to Ubuntu (instead of to FreeBSD); like our DNS resolvers, it doesn't use PF, and we already operate a couple of Ubuntu DHCP servers. In general Ubuntu is our default choice for a Unix OS because we already run a lot of Ubuntu servers. But we have lots of PF firewall rules and no interest in trying to convert them to Linux firewall rules, so anything significant involving them is a natural environment for FreeBSD.

(I'm the author of the linked-to article.)

cyberpunk2• 8 months ago

Why do you say OpenBSD stopped "supporting bind"? You mean they don't include it in the base system anymore since the switch to unbound?

I mean.. It's one pkg_add away. It's a weird constraint to give yourself if that was the problem, considering you absolutely had to install it on your replacement ubuntu servers.

somat4• 8 months ago

I am not very familiar with FreeBSD's pf but my understanding is that fbsd integrated it from OpenBSD and then proceeded to put a fair amount of work in making it more performant(multi core) while OpenBSD put most of it's work into improving pf's features, At this point the two pf's are different enough that they are not really compatible. OpenBSD can't really use much of fbsds multi core work and FreeBSD is A. Is a lot more hesitant about breaking backwards compatibility and B. would need get the queuing structures to work with their kernel. In short FreeBSD pf is like using an old fast version of OpenBSD pf

In fact if you asked me to explain the difference between obsd and fbsd it is exactly this. fbsd focuses on performance and obsd focuses on ergonomics.

markjdb• 8 months ago

The pf maintainer in FreeBSD has been doing a ton of work to bring more recent improvements over from OpenBSD, trying to bring them in sync as much as possible without breaking compatibility: https://cgit.freebsd.org/src/log/sys/netpfil/pf

The state of affairs you described is much less the case now than in the past.

popknobinfanny• 8 months ago

Root on ZFS is an easy sell for me. OpenBSD's ancient filesystem is notoriously flaky, and they have no interest in replacing it anytime soon.

I can't be worried that critical parts of my network won't come back up because the box spontaneously rebooted or the UPS battery ran out (yes it happens — do you load test your batteries — probably not) and their bubblegum-and-string filesystem has corruption and / and /usr won't mount and I gotta visit the console like Sam Jackson in Jurassic Park to fsck the damn thing.

Firewalls are critical infra — by definition they can't be the least reliable device in the network.

hnav2• 8 months ago

conversely, running a firewall on something like ZFS also sounds like too much. Ideally I'd want a read-only root FS with maybe an /etc and /var managed by an overlay.

lmm3• 8 months ago

Sounds like overcomplicating in the name of simplification. ZFS is a good, reliable, general-purpose system; often the right answer is to just put everything on ZFS and get on with your life.

throw0101c6• 8 months ago

Ideally I'd want a read-only root FS with maybe an /etc and /var managed by an overlay.

OpenZFS 2.2 added support for overlays, so you can have the main pool(s) mounted as read-only:

* https://github.com/openzfs/zfs/releases/tag/zfs-2.2.0

znpy• 8 months ago

conversely, running a firewall on something like ZFS also sounds like too much.

this makes no sense. firewalling does not touch the filesystem very much if at all.

what FS is being used is essentially orthogonal to firewalling performances.

if anything, having a copy-on-write filesystem like ZFS on your firewall/router means you have better integrity in case of configuration mistakes and OS upgrade (just rollback the dataset to the previous snapshot!)

p_ing3• 8 months ago

Firewalls are critical infra — by definition they can't be the least reliable device in the network.

This is why you have failover for firewalls. The loss of any single device isn't that important.

MBCook2• 8 months ago

Sure but you still want them as stable as possible. Needing (emphasis there) to fail over should be for emergencies, not standard operating procedure.

mmooss4• 8 months ago

This is the first I've read that OpenBSD's file system is "notoriously flaky", "bubblegum-and-string" (the opposite of the OpenBSD approach) or make "the least reliable device in the network". The reputation is the opposite.

visit the console like Sam Jackson in Jurassic Park

Consoles aren't so unusual for most server admins, IME. They're the most common tool.

gyniiggh6656• 8 months ago

It seems you’ve read too much general OpenBSD hype material and too little specific information about details like the filesystem. The OpenBSD filesystem notoriously lacks journalling support. It used to support soft updates, but that got removed too. There are no seatbelts. If you suddenly lose power, there is a high likelihood you lose data. OpenBSD is notorious for it.

ptidhomme2• 8 months ago

Filesystem is one of the rare areas (albeit crucial) where OpenBSD is flaky, tbf.

anthk2• 8 months ago

OpenBSD user here. I wish OpenBSD borrowed WAPBL from NetBSD.

hapless5• 8 months ago

OpenBSD's pre-journaling FFS is ancient and creaky but also extremely robust

I am not sure there is a more robust, or simple, filesystem in use today. Most networking devices, including, yes, your UPS, use something like FFS to handle writeable media.

I am not accustomed to defending OpenBSD in any context. It is, in every way, a museum, an exhibition of clever works and past curiosities for the modern visitor.

But this is a deeply weird hill to die on. The "Fast File System," fifty years old and audited to no end, is your greatest fear? It ain't fast, and it's barely a "file system," but its robustness? indubitable. It is very reliably boring and slow. It is the cutting edge circa 2BSD

edit: I am mistaken, the FFS actually dates to 4.1BSD. It is only 44 years old, not 50. Pardon me for my error.

yyyk• 8 months ago

OpenBSD FFS is robust in the sense of 'it is unlikely an FFS bug will lose your data'. But it is ancient, and, well, there are reasons for filesystem developments in the last half century, like 'not losing your data thanks to blackouts or hw bug'.

The lack of at least a journaling FS is inexcusable in a modern OS. Linux and Windows have had it for 25 years by now, and we could argue softupdates are roughly equivalent (FreeBSD has had SU+J for years now too).

kuon2• 8 months ago

I was using OpenBSD for my firewalls for a long time, but with the arrival of 10Gbit/s ethernet, I realized that I had to move back to ASIC based firewalls.

Yes, you can forward 10Gbit/s with linux using VPP, but you cannot forward at that rate with small packets and stateful firewall. And it requires a lot of tuning and a large machine.

A used SRX4200 from juniper runs at around 3k USD and you can even buy support for it and you can forward at like 40Gb/s IMIX with it.

I still prefer PF syntax over everything else though.

kev009• 8 months ago

You can definitely build an x86 system to route 40Gb/s with small packets for under $3k and it's been the case for many years. A Xeon-D can hit 100gbps forwarding and filtering.

OpenBSD is going through a slow fine grained locking transformation that FreeBSD started over 20 years ago. Eventually they will figure out they need something like epoch reclaimation, hazard pointers, or rcu.

kuon2• 8 months ago

Thats also what I thought, but on my test system under freebsd with mellanox 25Gbit/s nic and ryzen 9 I peak at around 2Mpps.

hapless5• 8 months ago

I just today deployed an $800 mikrotik in my house that can route 10 gbps at wire speed. on the CPU. with firewall and nat rules applied. no joke. 4 million packets per second is, like, a lot, post-filtering and with any substantial packet size.

This was doable back in 2008 with about $15k of x86 gear and a Linux kernel and a little trickery with pf_ring. The minute AMD K10 and Intel Nehalem dropped, high routing performance was mostly a software problem... Which is cool as hell, compared to the era when it required elaborate dedicated hardware, but it does not make it cheap or easy. Just, commodity. Expensive commodity.

Now you can buy a device off the shelf for $800 that will do it on the CPU, to avoid the cost of Cisco or Juniper, and it has a super simple configuration interface for all the software-based features. Everything you could do in L3/L4 on a Linux platform in 2008, for like, 1/16th the price, with vastly less engineering effort. It is just like, a thing you buy, and it all kinda works outta the box.

No pf_ring trickery, no deep in-house experience, just a box you buy on a web site and it moves 10 gbps with filtering for $800

There's no real magic here: they use absolutely shockingly enormous ARM chips from Amazon/Annapurna. You can build an $800 commodity platform that rivals a $15k commodity platform in 2008, and both of them replace what used to cost $500k.

Is it as good as Cisco or Juniper? oh, certainly not. Will it route and filter traffic at much greater rates, for $800, than anything they have ever been bothered to offer? ABSOLUTELY

versteegen• 8 months ago

I'm really confused by "about $15k of x86 gear ... The minute AMD K10 and Intel Nehalem dropped, high routing performance was mostly a software problem". What kind of $15k machine would you have needed? That's a heck of a lot more than even the most expensive K10 2008 CPU (which according to Wikipedia seems to be Opteron 8384 (quad core, 2.7GHz, 1.0GHz HT, $2149 November 2008), supports up to 8 CPUs per machine, I guess that's what you mean.)

asteroidburger• 8 months ago

Who is the "we" here? I've poked around a few pages on this fellow's site, and apparently haven't found the right one to answer that.

somat4• 8 months ago

Where he works... Or perhaps more accurately his co-workers. which is the domain. The university of Toronto.

hapless5• 8 months ago

This post sounded faintly crazy to me, so I went into a little wiki-hole consisting primarily of mailing lists and dev docs

Turns out, the main reason `pf` is non-portable is that half of it runs inside Berkeley-type network stacks, often in kernel space, but the remainder is in user space.

So the miserable single-threaded `pf` on OpenBSD is still, in some part, single-threaded on FreeBSD, but for certain rule-sets, you will get the benefits of FreeBSD's intensively re-entrant and multithreaded TCP/IP, because those parts of `pf` are embedded in the network stack.

So depending on workload, a given `pf` configuration on OpenBSD might be perfectly equal to its FreeBSD counterpart, or hundreds of times slower. I feel like this gives a lot of context to the OP's grousing around "10 gbps"

P.S. To confess my own biases: a port of a `pf` configuration to a platform where some rulesets are high performance and others are not, that would not be very attractive to me. An improvement, but not a solution. I would be looking to move to a Linux stack. Baby steps, I guess. I have done worse things to better people!

P.P.S. I suspect this coupling between a re-entrant TCP/IP stack and a single-threaded firewall process is also why FreeBSD `pf` is never even close to feature parity with its OpenBSD counterpart -- it is just easier to do new stuff with a simpler model

Moving from OpenBSD to FreeBSD for firewalls

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