Raspberry pi4 2.5gbps ethernet adapter?

Hey all.

I got a huge upgrade on my internet for almost free...i love my rasp with openwrt so i'm not getting rid of it.
I need to know which adapter's or which chipsets are the best for 2.5gbps on the pi that works well with openwrt?

Any chipset known for being better or more compatible?
Any good recommendations? That would be very welcome and i appreciate in advance your support.

Realtek is the only option, if you don't want to spend more on the adapter(s) than on the Pi.

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Any specific model of chipset or any will work? I was able to setup the 1gbps adapter following the tutorials but i'm wondering if we have any chipset that is more compatible or have better support? Or are all Realtek same way to enable and use?

You won't find any chip details for most adapters anyway, but so far I haven't seen any posts about non working adapters.

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Cool thank you for your help friend \o.

What speed is your upgraded internet connection?

If you only use 1 x 2.5G, then it's no use, but if you want to use 2 x 2.5G, there is not enough bandwidth for the USB ports on Pi4, I recommend you to look into other platform.


BTW that's one of the big improvements in the Pi 5 - bandwidth is no longer shared between the two 3.0 ports, so if you are using both of them it's an effective doubling of bandwidth.

That said, hooking 2.5 gigabit Ethernet to a Pi seems like the wrong way to do things, given that there are a lot of Rockchip devices with more capable CPUs and native 2.5 GbE.


2.5gbps and is cheaper than what i had so it's a must go...

YEah i heard, the idea is that i will use it only for adblocking and dns so do you still think the bandwidth will be bad ?

If you have 2.5G internet, you need 2x 2.5G adapters to take advantage of it. Otherwise, you'll always be limited by the 1G port on either the lan or wan, meaning that there is no value to adding a single 2.5G adapter. (the traffic will flow at a maximum of 1Gbps because of the other port). And, it has been stated that the Pi's USB port bandwidth will be the limiting factor here (since the 2x USB 3.0 ports are on the same USB bus).

So, my recommendation is this:

  • try to get 2x 2.5G adapters and see what kind of performance you get (make sure you can return the adapters if they won't otherwise be useful to you)


  • Simply use your 2.5G internet connection as-is (yes, go for the upgrade on the service side), but live with the 1G bandwidth limitation of your main router.

(or, upgrade to a more capable router that already includes 2.5G or 10G ethernet connections).


I should also add that you'll need to ensure that the device downstream of your router also supports >=2.5G on at least one port. So, if you have a switch, you need that to have higher bandwidth on at least one port, otherwise, you'll still be limited by a 1G link between the router and the rest of your network. A switch port that is >=2.5G will ensure that the uplink isn't the bottleneck.

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Ah yeah i did buy new switches and also a new 2.5 pciexpress card now testing time xD Thanks for your advices.

Do you by any chance know what's the package to install for the 8156B chipset?


There are Intel N95/ N100 (x86_64) based mini-PCs with (typically) 4 ethernet ports (obviously look for 2.5GBASE-T) available on the big market places for rather attractive conditions (130-250 EUR/ USD).

Another alternative would be to add two 2.5GBASE-T PCIe ethernet cards (15-20 bucks each) into a used skylake/ kabylake i5 SFF system from one of the big four (Dell, Fujitsu, HP, Lenovo) for roughly 50 bucks, but the former will probably pay for itself on the electricity bill within due time.

I appreciate it but i'm not changing my pi now, first i want to have some tests.

There are older Celeron J4125/N5105 with dual/quad 2.5G and much cheaper, if Pi4 is enough for routing I believe J4125 won't lose to it.

We will see, i'm pretty sure the pi will handle 2.5...it's not full duplex so my chances are higher !

We wait and see xD

Yeah but then it comes down to energy consumption on those celeron models...there are many many options tho lets see!

One reference for you is, USB ethernet has overhead and that's why a 5GbE USB dongle can only achieve ~3.3Gbps max throughput on a 5Gbps USB 3.1 Gen 1 bus (this is also the spec of Pi4's USB). And if you need to buy extra USB 2.5G NIC I would just pay a bit more to get something else, at least those are more integreated solution

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Yes i was already aware of it we will see thanks mate.