I just installed a PCIe-x16 card into my motherboard and attached a nvme M.2 SSD into it, but it will not show in array devices. I want to use it as a cache pool. I've read somewhere about my motherboard perhaps needing to support "PCIe bifurcation"? Any help on the matter would be greatly appreciated. I couldn't really understand where to look in the diagnostics logs.

Here are some useful information about the system:

 

Motherboard: MSI H97I AC (MS-7851) , Version 1.0

PCI card: ASUS Hyper M.2 X16 Card V2 (fits up to 4 SSDs)

Kernel: Linux 5.19.17-Unraid x86_64

 

I'm new to unraid, so please let me know if I can provide any other useful information.

server-diagnostics-20221213-2121.zip

39 minutes ago, CarlDrogo said:

I've read somewhere about my motherboard perhaps needing to support "PCIe bifurcation"?

Bifurcation is a way to divide the PCIe lanes assigned to a particular motherboard slot to multiple devices.  Ideally, in your case, the motherboard BIOS would allow you to split the x16 PCIe slot into x4x4x4x4 so that each of the M.2 SSDs on the Asus Hyper M.2 would get 4 PCIe lanes.

 

The best my main server motherboard can do with the x16 slot is x8x4x4 so I could only have three M.2 SSDs on that ASUS card plus the one on the motherboard.  You will have to check in your BIOS to see if bifurcation of an x16 PCIe slot is supported.

If there's no bifurcation support you should still be able to use it but only for one drive, and it needs to be installed in the slot that is wired to the first lanes (closest to back of server).