4036e Eth to IB bridge not passing NAT

I know the 4036E is old as hell but it solves a problem I am having. Without going into huge detail I have a 4-node cluster (hyper-v) (home lab). after upgrading to server 2022 networking was broken. almost all traffic made its way through my gigabit ethernet even when specifying the IB subnet. it would pass through my gig link. its pretty awful performance when hyper-converged. I spent weeks working with Microsft and they never could tell me why it’s happening.

OK enough with the why. My issue now is I decided to drop the 1gig ethernet all together which is actually a better option as my VMs will get their own 40gig links and my Hyper-v netwroking will be way simpler.

I did a quick bit of research to see what eth to IB gateway I should use and almost everyone said to grab a 4036E. turns out there were 2 of them on eBay for $200 shipped. couldn’t pass it up.

After getting them I figured they would be pretty simple to setup…Wrong. there is very little documentation on the Bridge and It turns out that for all the recommendations no one seems to have ever used these. I have fumbled around enough and managed to get bidirectional pings working from an IB host to my router…but this is where it all falls apart. NAT doesn’t work. anything past my router is unreachable. the switch can see 1.1.1.1 but the server can’t. As a test I added another address to my router that’s outside the subnet…ping works. so it’s not a default gateway thing as it must have used my router to see the other network. So I have local connectivity but no Internet.

I am open to all suggestions and there is no real config on these switches so if factory defaulting again is the quickest way that’s fine.

I really just want to get this moving but ultimately I have 2 switches and dual IB cards in all the nodes. was hoping to do a failover cluster in the end.

4036E is very very old device. which has been EOL more than 10years.
But anyhow, you can search User mannual from google, and I remeber in UM it mention how to configure HA for a cluster.

I have the user manual and do think I have clustering working but the manual skips over the Eth to IB bridge feature and how it routs packets. that is my main concern. If I had that working and never made clustering work I would still be ahead.