NPIV support on Windows Server 2025 Hyper-V

[Andrea 'ML' Suatoni]

Hi,

Is there anyone here which has tested Windows Server 2025, with Hyper-V
role, and using the Virtual San (NPIV) feature?

We are having a strange issue: HPE Synergy frame, with 12 Gen11 blades,
each with HPE 5830 32Gb FC HBAs mezzanine. The frame hosts two different
Hyper-V failover clusters, one running on Window Server 2022, the other
on Window Server 2025. Firmware / Synergy SPP is at the same level on
all the blades, the drivers (at least the one for the FC HBA, a
Marvell/QLogic chip) seem to be the same on both OS, the clusters have
their own CSV hosted on a SAN-connected NetApp.

I've been requested to test Proxmox VE in one of the two clusters, and
since they are both running already quite a number of VMs (it's a
staging environment) andt we don't have spare physical servers right
now, my idea was to run Proxmox VE as nested OS in Hyper-V 2025. No
issue at all as long as the Proxmox disk(s) are hosted on VHDX located
on the cluster's CSV, but then another requirement came: we need now to
test Proxmox VE cluster capability. And since the request is to test
Proxmox VE as much as possible similar to a bare-metal installation, I
thought it would a nice idea to create some vSAN and present the NetApp
LUNs straight to the VM.

Except it doesn't work on Window Server 2025:. Using the GUI or
PowerShell doesn't make a difference, but Hyper-V states the HBAs do not
support NPIV. The Marvell/QLogic docs  state the opposite, and as far as
I know NPIV is still a feature on Hyper-V 2025.

After having fiddled a lot with checks, different test, even upgrading
one of the 2025 hosts with the latest HBA firmware (a very minor
release, just in case), I still cannot create the vSAN. Since I couldn't
find any release note, official statement or documentation from either
HPE or Microsoft, out of ideas I tried to create the vSAN on Hyper-V
2022 nodes, which as written have the exact same hardware/firmware
combination (and as as far I can tell, also the same miniport driver).
BANG! It worked in a snap!

My test seems to indicate that in WS 2025 is a shortcoming of the
firmware/miniport combo which is not exporting the NPIV feature to the
Hyper-V layer, but it may be also a bug in Hyper-V 2025. SInce NPIV /
vSAN in Hyper-V are rarely used, if ever, maybe nobody has noticed it.

Have you ever hit the same issue? Is there anything else I should check,
before opening an hopeless support case with HPE? (hopeless because the
last time I had a case with HPE and Microsoft sharing an issue, it
resulted in a ping-pong two months long which went nowhere).

Thanks!

Andrea

PS: no, iSCSI is not a valid alternative, we've stopped using it since
we moved to SAN on fibre channel.