Minimum Hardware Specs to run Open WRT on PPPoE on a Gigabit Connection

Hardware Questions and Recommendations
4

PPPoE can be quite a CPU-hog, so 1/1 Gbps will need a sufficiently beefy CPU or a PPPoE offload (with the typically associated loss in generality).

Which will all be downstream from the router sio should not matter...

Running iperf on a router is a quite different loads from actually traffic routing, so if you want your router to act as traffic source/sink for 1/1 Gbps tests, you will again have to look for enough and beefy enough CPUs.... (consider using a SBC like raspberry pi4 B as iperf server inside your network).

Given how vague your requirements are this seems hard to answer...

Yes, as I said PPPoE is quite a hog. It would be nice if this feature would be removed at one poiont, but for the time being many ISPs use PPPoE so make sure your router can handle it at the desired traffic rate...

Not sure we can give more guidance here than that article unlerss you nail down your requirements .:wink:

5

It's hard to tell exactly but a rough estimation based on my tests would be something like intel n5000+ or at least 2500 passmark score. You'll probably won't find anything with less than 4gb of ram anyways so that doesn't matter that much

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PPPoE can be quite a CPU-hog, so 1/1 Gbps will need a sufficiently beefy CPU or a PPPoE offload (with the typically associated loss in generality).

Got it, but how much of a beefy CPU are we talking about?

Which will all be downstream from the router sio should not matter...

Right, thanks.

Running iperf on a router is a quite different loads from actually traffic routing, so if you want your router to act as traffic source/sink for 1/1 Gbps tests, you will again have to look for enough and beefy enough CPUs.... (consider using a SBC like raspberry pi4 B as iperf server inside your network).

Right, but again, how much of a beefy CPU are we talking about? Since you mentioned a Raspberry Pi 4, a Quad core ARM CPU running at 1.8GHz, is beefy enough? I assume? And How much RAM to keep up with that?

Given how vague your requirements are this seems hard to answer...

Sorry for that, I thought I gave all the requirements to what I planned to do. So what did I left out? What kind of detail do you need to know to answer that?

Not sure we can give more guidance here than that article unlerss you nail down your requirements .:wink:

My bad, I guess? If I wasn't specific enough, just tell me what I failed to provide so I can say it.

7

Higher end ARMs will likely do (IMHO don't bother with A53/A55) as will recent x86 cores, but it really depands on your load how many of these you want and at what frequency (and what memory system is needed to actually feed these CPU cores).

So a number of folks seem happy with raspberry pi4B performance, so Arm A72 and above seem well suited (ATTENTION: the pi is not a natural base for a router as it lacks a few thinks, like a second ethernet interface and competent wifi, so if you want an arm based router look somewhere else, unless you have a pi4/5 idling around and enjoy the challenge). RAM is for routers typically< not all that big a deal... (but then that can change depending on what services you run on there, some blockers use relatively laerge lists and hence are memory hogs...)

  • Some free power to run some more software in case it's needed;

Leaves much up to one's phantasy :wink:

See above ...

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8

Some SoC have hardware offload which doesn't really need too much CPU power for PPPoE, just like the MT7621AT (very common on lower end routers now).

9

Your requirements and the exact phrasing is what makes this difficult, if not impossible to answer. If I follow your request to the letter, you want something that does PPPoE at 1 GBit/s line speed (that is already not trivial to do, without a survey of rather different hardware, combined with adguard home (this is easier, in regards to the base load - but harder to answer when it comes to really large blocklists or advanced filtering rules, so quite some variance between minimal, expectable-median and worst case situations). iperf is useless for the router itself, but drives up the requirements considerably - and "Some free power to run some more software in case it's needed" is completely impossible to evaluate in terms of CPU/ storage and RAM needs.

So you come up with a very fuzzy/ vague list of requirements (might be obvious to you, but isn't for anyone else), while at the same time with a massive variance between minimum, expected median and maximum system requirements. But at the same time you're requesting an exact specification for the minimum system requirements, with no margin for overshooting this - that's simply not possible.

So you have 500Mbps-1Gbps fiber and need a router READ THIS FIRST is still valid, some N100 based x86_64 system with four 2.5GBASE-T ports does meet your listed requirements, but it does overshoot your target performance - still, around 120-230 EUR, plus switch(es) and AP(s) is a very reasonable choice for your situation, leaving substantial margins.

Would filogic 820/ 830/ 880 meet these requirements? Perhaps, but it does rely on hardware flow-offloading for this, which is a little fragile, especially in combination with PPPoE and it might be marginal for iperf3 on the device and "Some free power to run some more software in case it's needed".

Would one of the newer rockchip based NanoPi meet them? Quite probably, but with fewer onboard ethernet ports and the same requirements for external switches and APs - but especially the newer ones are still waiting to be fully supported. The same goes for the RPi4/ RPi5, with the additional complication of those needing a USB3 ethernet card on top.

Would ipq807x meet the bar? Very likely not, not with PPPoE and without NSS acceleration.

What about mt7622? Similar situation as filogic 820/ 830, but with less SOC performance - it may be just enough, but with your fuzzy additional requirements and seeing it slowly disappear from the market (in favour of mt7621a+mt7915DBDC on the low-end and filogic 820/ 830 on the mid- to high-end), this wouldn't be my first pick right now.

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11

Is there anything specific that is needed to enable this, or will it just happen by default?

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You probably need to expand on this - are you referring to OpenVPN / Snort / SQM / Docker containers ?

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  • Some free power to run some more software in case it's needed;

Just to make it clear, what I meant by that is just a spare processing power to do all of the other tasks and to install some minor packages that it's not intended to take a lot of processing more, like changing the Luci Interface colors, editing text files via ssh and stuff like that.

Just enough to do the other tasks reliably, but still have some spare space to run those kinds of minor things, nothing that should impact throughput and processing power that much.

15

If I follow your request to the letter, you want something that does PPPoE at 1 GBit/s line speed (that is already not trivial to do, without a survey of rather different hardware, combined with adguard home (this is easier, in regards to the base load - but harder to answer when it comes to really large blocklists or advanced filtering rules, so quite some variance between minimal, expectable-median and worst case situations).

About AdGuard Home, I don't plan to make any fancy blocklist or that much of a advanced filtering other than the ones that are already recommended, since it's intended for home use, I want just enough to block most ads, even if that means failing to block ads on one specific site or another.

"Some free power to run some more software in case it's needed" is completely impossible to evaluate in terms of CPU/ storage and RAM needs.

I just posted something clarifying that, but short answer, what I meant by that is just enough to install some minor packages like that one that changes Luci's interface colors, that one that updates OWRT using Attended Sysupgrade, pciutils and stuff like that, nothing that, at least as far as I know, should impact throughput and processing power that much.

Sorry for the phrasing, in my mind, that was clear but seeing that so many people find it so difficult to understand it, it was clearly a bad way of expressing that.

So you come up with a very fuzzy/ vague list of requirements (might be obvious to you, but isn't for anyone else), while at the same time with a massive variance between minimum, expected median and maximum system requirements. But at the same time you're requesting an exact specification for the minimum system requirements, with no margin for overshooting this - that's simply not possible.

Besides that "some free power..." part, based on what I already said a planned to do, what thing can cause so much of a variance between minimum/expected/max throughout performance you need to know to answer it with a reliable level of precision?

I'm a layman on this matter, I'm just curious about networking, my level on that is still really basic and this is one of my first contacts with OWRT, besides that, English isn't my first language so it's expected that I have some misconceptions/misinterpretations. If you don't explain to me why my wording or intentions of use weren't properly described for you to answer it, not only will I remain in doubt, but I will also keep making the same mistakes again.

In the same way it's obvious to you that my question was fuzzy and vague, it's obvious to me that this part of the answer also sounds fuzzy and vague.

I looked at all those SOCs you mentioned, and all the ARM ones were at least a quad-core at 1.4GHz, so is it safe to assume that a quad core ARM CPU at 2.0GHz will be enough? What about RAM?

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Recommendation for OpenWrt as a basic router https://openwrt.org/supported_devices/864_warning
Minimal 16MB of flash
Minimal 128MB of RAM

Additional requirements for Adguard Home https://openwrt.org/docs/guide-user/services/dns/adguard-home
Minimal 100MB free flash
Minimal 50MB free RAM
Minimal dual-core

So combined 128MB flash and 256MB RAM are minimal recommended

A couple of processors that are suitable for Gigabit routing:
dual-core Cortex-A72 - i.e. NanoPi R4S 4Gb
quad-core Cortex-A72 - i.e. combo Raspberry Pi CM4 (cm4001000 or cm4002000) + DFRobot Routerboard
quad-core Intel N5105 with i226-V NIC
quad-core Intel N100 with i226-V NIC - see https://forums.servethehome.com/index.php?threads/cwwk-topton-nxxx-quad-nic-router.39685/

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17

While that may be true on paper, for a very small blocklist - the more common blocklist sizes in the 5-6 figure range (and that is still rather modest) can kill (OOM) a 512 MB RAM device easily. Meaning those figures -while technically correct- are way off in practice.

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18

I can not really answer your question, but...
My dual core arm A9@1.6GHz (mvebu, turris omnia) with 1 GiB of RAM and a few GiB of storage is doing the following well:
routing, firewalling, NAT
sqm traffic shaping (105/45 on a 116/46 Mbps link)
dual WiFi, 2.4 and 5 GHz
turris pakon (network monitoring and logging using suricata under the hood)
mild file sharing with samba
adblocking (using luci-app-adblock with the default lists)

All of this works reasonably well, but at 105/45 it is far below what you ask for and I am confident an omnia would run out of steam well before reaching your target access capacity (also the omnia is currently a bit outdated and I would not buy a new one, before the design is refreshed, but snce it is underpowered for you anyway this is not really an issue)

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19

With adbock-fast - Blocking 352616 domains - my RAM usage is around 200MB
But with Adguard Home blocklists a safer choice for minimal RAM would probably be 1GB

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21

Estimating roughly, performance akin to Intel N5000+ or a minimum 2500 PassMark score is suggested based on tests. Typically, systems with less than 4GB RAM are uncommon, so it's not a significant concern.

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22

Which tests? Any source for that? I find that number a tad high.

To wit: My Sophos XG86 manages to route just shy of 900 Mbit/s, not synthetic but real-world on a PPPoE(!) connection. Its Atom E3930 is listed with a PassMark score of 928. I'm positive it would have no problem routing the OP's 600/350. I'm not saying more biggerer isn't more betterer, but the OP is asking for the minimum.

image

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23

This cannot be answered any better than here.

24

These days, especially at the higher end of the wan speed spectrum (because expectations tend to rise accordingly), I always mentally add enough margins for sqm/cake to the (implicit) requirement list - and at least the j1900 passes out around ~830 MBit/s doing that - and we have quite competitively priced (new) N100 systems these days (obviously there may still be good-enough bargains on the used market, so if you stumble about those, by all means, go for it - its price just needs to be in line with the 130-230 EUR needed for a new N100).

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26

Someone took a lot of time to break the numbers down.

The write up is in the link I provided above.

28

I'm going with the mods pinned it in 4 days to let it do all the talking.

I'll trust them.

Sorry, I'm not here to argue; would actually like to see less of it.