Re: Windows domu DRBD backend problem

["Tu Dinh" <ngoc-tu.dinh@xxxxxxxxxx>]

Hi Attila,

On 22/04/2025 21:00, Kotán Attila wrote:
> Hello,
>
> I use many windows as xen domu and installed your winpv driver. I
> experience the problem in very special case, but not an unique.
> The windows freeze when the disk backend of domu is DRBD and the the
> DRBD secondary node (DRBD status=secondary) goes to disconnect, for
> example i reboot the computer.
>
> The problem is reproducible:
> - Two DELL server with PERC RAID controller
> - RAID0,1,10 virtual disks boot side
> - DRBD backend is an RAID virtual disk
> - Primary side installed an Windows with XEN VBD driver
>
> If the secondary side goes to offline, the DRBD status change to
> disconencted, but working continuously, but the windows freeze.
>
> - No problem with linux domu
> - No problem until the winpv VBD install
> - No problem if the DRBD backend is not a RAID virtual disk (for example
> with M.2 NVME backend)
>
> I tested the
> - Winpv driver 9.0 (signed)
> - Winpv driver latest (testsigned)
> - citrix xenserver driver (managementagent-9.4.0)
> and the problem is occurs in everyone.
>
> Everyting workin fine until the secondary DRBD node goes to offline /
> disconnected. I think i tested many situation and finally left the WinPV
> driver what is caused the problem i mean.
>
> Do you have any tipp, what can i set?
> How can i debugging this problem?
> I try to see what happened on linux domu when the DRBD status change,
> but i can't find anything.
>
> Have any ideas?
>
> Thank you and best regards.
> Attila
>

If the problem doesn't happen with the DRBD NVMe backend then it
suggests a problem with DRBD itself, which is not handling failovers
correctly.

Do you have any relevant kernel debug outputs when the freeze happens,
as opposed to during a normal failover (e.g. with DRBD NVMe)?

Best regards,
Tu Dinh


Ngoc Tu Dinh | Vates XCP-ng Developer

XCP-ng & Xen Orchestra - Vates solutions

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