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pfSense and 10Gb SFP+ issues

Hey all, i’ve been building up my network to be able to make use of the >1Gb incoming connection from Comcast, but i’ve had some issues with my pfSense box (now running on a r210 II) and the 10Gb adapter i have, specifically the Supermicro AOC-STGN-i2S (x520-DA2 clone running a 82599 controller)

When using an SFP>RJ45 adapter, (I have one from I can’t seem to get it to negotiate any link to the modem, which has a 2.5Gb port. on the pfSense side, the speed/duplex setting only shows no preference or 10Gb. would the SFP adapter be in control of what speeds are shown here, or is it only the NIC that determines available links?


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Until someone with actual knowledge answers, I would venture some thoughts.


I don’t think you can do 2.5gbe on older hardware.

2.5 might seem like an intermediary speed, given that is it between 1 and 10 gig.
But, as a standard, it has not rolled out very far yet.
10gbe and 1gbe are pretty established.

I would posit the card would work at 2.5, even if the modules could work for it.
I would try and manually set it the router to 1gbe, and see if that will work?

the nic and the adapter would have to work with the speeds needed, but they should have “lowest common denominators” they can work with.
So a 25gbe capable module should work in a 1gbe capable nic, as long as the nic’s on moth ends can negotiate it.
Same with 2.5gbe

You might want to find a 2.5gb nic, and can probably use the same adapters

But Please do do your own research, and see if you can find any sfp+ nics that will work with 2.5gbe, at reasonable prices…

you also might be better off with a switch, which has a 2.5gb socket (connect to router) and a 10gbe socket (connect to pc) and 1gbe sockets (connect to xbox, telly, accesspoint, whatever)

but this might be throwing bad money after good…

Not all SPF+ to RJ45 adapter modules support NBaseT. STH did a guide a while back:

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I don’t think SFP+ auto negotiates…even with an RJ45 adapter.

I tried with one of the Wiitek ones they used as well, no dice. I’m wondering if it is something at the driver level, as according to the spec for the ethernet controller, it should show 10Gb/1Gb rates, but my listing only shows

while the other port on this adapter, connected to my core switch, shows 10Gb Twinax, and it is running autoselect on both sides.

I guess my main question would be If the SFP module itself would be playing a part in the link speed (i.e. shows 10Gb on the sfp side, and whatever speed (1, 2.5,5,10) on the RJ45 side, or if it is simply a media converter, nothing more.

also curious if anyone here has tried a media converter that has a nbase-t rj45 and a 10Gb SFP on the other side, as i found one for 170 that looks like it might work for my needs, but i’m fairly new when it comes to the 10Gb world for the most part

(Don’t know if this is the right product brief, but if so, It looks like the the adapter doesn’t support NBaseT, or anything but 10GbE with a non-optical connection:

Most 10Gb adapters don’t support 2.5 or 5Gb connections at all. You need something that explicitly supports those speeds. The transceiver will also need to support it.


This is what i’ve been looking at -

and the Intel Ark shows 10/1Gb connectivity for the 82599ES controller, (ARK)

If i’m looking at this correctly, assuming I use the same NIC, I would need to use something like this media converter in order allow the NIC to negotiate at 10Gb, and the modem to work at 2.5.

as for the SFP to RJ45 adapters, they are effectively passing the speed and duplex negotiation to the NIC, so all 3 components would need to support 2.5Gb for it to work, right?

Maybe the X550 series would work:
(although double check you get the features you want in the OS platform you need)

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I think this is for the opposite application you’re looking for. It’s to take a 1/2.5/5/10 gig copper connection and pipe it over 10 gig fiber:

If used to pump a 10g connection up a 2.5 link, I hope it’s got good flow control or buffering, or you might be losing some of your bandwidth to inefficient media access control (with resultant lost packets and retransmission overhead).

you can buy 2.5gb pci cards for pretty cheap on ebay. just pick one of those up, assign your wan to that port and call it fixed, don’t go buying media converters lmfao. If that card works for you great, then if you have issues later on (is cheap card) qlogic has some things but are some serious coin. If you want pfsnese to route at 2.5gb give it a 2.5gb port!

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