Hi team!!

The TLDR is: I swapped my dual 2.5Gb NIC for a dual 10Gb NIC but the 10Gb NIC is faulty and causes the server to shutdown (gracefully thank goodness #noparitycheck).

I have put the 2.5Gb NIC back in but I am having multiple issues such as a reference to eth0 not existing even though there is an entry for the card which I have now re-installed.
None of my attempts to configure the network has worked and then I noticed that the link lights for the card do not illuminate. I used the onboard 1Gb NIC and that works fine.

My suspicion is that the 2.5Gb NIC is not happy because its sharing an IOMMU group with an Add-on SATA card I'm using... this was never an issue as both the SATA card and the 2.5Gb NIC have been running in the system for almost a year without issue.

So the question is how do I move the Realtek 2.5Gb ethernet controller into its own IOMMU group. Highlighted in red in the image...

I tried SpaceInvaderOne's video from 7 years ago but that resulted in the system not booting because it couldn't find the USB drive - so I reverted that change it boots normally. I can only assume that things have changed in 7.1.4.

Can someone please let me know how I do this?

Thanks!!!

Edited October 7, 2025Oct 7 by thaoggamer
SET TO SOLVED

4 hours ago, thaoggamer said:

So the question is how do I move the Realtek 2.5Gb ethernet controller into its own IOMMU group

IOMMU groups are controlled by the hardware; you can try enabling PCIe ACS Override in the VM options to see if it helps.

Thanks @JorgeB that worked.
I set PCIe ACS Override to "Downstream" and also disabled allow unsafe interrupts - the system seems to be working fine now.

Edited October 7, 2025Oct 7 by thaoggamer