[SOLVED] Win 2K25 BSOD on Backup

[pmbaeum]

Hi,
I'm currently running a new Server with Proxmox 9 and a single Windows 2025 VM on it, serving as Exchange Server in our Environment.
I installed Virtio 0.1.285 SCSI drivers.
For Application awarene Backups I'm running Windows Server Backup, which was fine when I tested in the beginning.
Now after everything is productive I'm running into problems:
The Server crashes when the update is nearly complete - I assume that's when the logs should be truncated and the vss worker is being executed.


I already tried different Versions of the VirtIO driver and set my SCSI Controller from "VirtIO SCSI Single" to "VirtIO SCSI" => No Change.

More Info:


qm config 131
agent: 1,fstrim_cloned_disks=1
balloon: 0
bios: ovmf
boot: order=scsi0;ide2;net0;ide0
cores: 12
cpu: host
efidisk0: local:131/vm-131-disk-1.qcow2,efitype=4m,pre-enrolled-keys=1,size=528K
ide0: WD8TB:iso/virtio-win-0.1.285.iso,media=cdrom,size=771138K
ide2: none,media=cdrom
machine: q35
memory: 65536
meta: creation-qemu=9.2.0,ctime=1754487133
name: EX-AHBSV03
net0: virtio=BC:24:11:8B:74:B0,bridge=vmbr0,tag=210
numa: 0
onboot: 1
ostype: l26
scsi0: local:131/vm-131-disk-0.qcow2,cache=writeback,size=250G,ssd=1
scsi1: ZFS8TB:vm-131-disk-0,cache=writebacksize=450G,ssd=1
scsi2: ZFS8TB:vm-131-disk-1,cache=writeback,size=1500G,ssd=1
scsi3: ZFS8TB:vm-131-disk-2,cache=writeback,discard=on,size=1500G,ssd=1
scsi4: WD8TB:131/vm-131-disk-0.qcow2,backup=0,cache=writeback,size=3500G,ssd=1
scsihw: virtio-scsi-pci
smbios1: uuid=d4fac7e5-0327-4c1f-80ed-e7115a1d14a7
sockets: 1
tpmstate0: local:131/vm-131-disk-2.raw,size=4M,version=v2.0
vmgenid: f31c35f9-c471-46a2-8ed1-9f75dd3daf19


uname -r
6.14.11-2-pve

Since I read something about AMD CPUs causing this:
I'm running an Intel Silver 4314 CPU

 

[uzumo]

The Windows virtual disk module vhdmp.sys attempted to write to read-only memory. This is recognized as an issue in Windows Server 2025.
* Windows Server Backup creates a virtual disk named vhdx as the backup destination and performs the backup. This issue arises from that process.

Why are you asking on the Proxmox forum?

You should ask your questions on the Microsoft forums.
*Since it likely cannot be analyzed with a mini dump, you will need to submit a full dump to Microsoft's paid support.

 

[pmbaeum]

I assumed it could be a SCSI/VirtIO Problem and hoped someone would have means to mitigate this. But if it's a Windows error I will take it there. Thank you.

 

[uzumo]

If you haven't applied the latest OS patches, try installing them.

 

[pmbaeum]

Indeed WSUS was still blocking KB5063878.
After that I still had BSOD Issues, but at least with another Error Message (kernel).
Installing virtio-win-0.1.285 SCSI Drivers helped.

Current working config, as it may help others:
scsihw: virtio-scsi-single
scsi0: local:131/vm-131-disk-0.qcow2,cache=writeback,iothread=1,size=250G,ssd=1
scsi1: ZFS8TB:vm-131-disk-0,cache=writeback,iothread=1,size=450G,ssd=1
scsi2: ZFS8TB:vm-131-disk-1,cache=writeback,iothread=1,size=1500G,ssd=1
scsi3: ZFS8TB:vm-131-disk-2,cache=writeback,discard=on,iothread=1,size=1500G,ssd=1
scsi4: WD8TB:131/vm-131-disk-0.qcow2,backup=0,cache=writeback,iothread=1,size=3500G,ssd=1

Get-WmiObject Win32_PnPSignedDriver | Where-Object { $_.DeviceName -match "VirtIO" -or $_.DriverProviderName -match "Red Hat" } | Select-Object DeviceName, DriverVersion, DriverDate, InfName, DriverProviderName


DeviceName : QEMU FwCfg Device
DriverVersion : 100.101.104.28500
DriverDate : 20250907000000.******+***
InfName : oem3.inf
DriverProviderName : Red Hat, Inc.

DeviceName : Red Hat VirtIO SCSI pass-through controller
DriverVersion : 100.101.104.28500
DriverDate : 20250907000000.******+***
InfName : oem21.inf
DriverProviderName : Red Hat, Inc.

Now both PBS-Backup and wbadmin run without errors.