Identical diskidentifier from template breaks backup

Question

After creating a VM from a template or creating a new disk based on a disk stored in library; the vhdx always has the same diskidentifier as the source vhdx (Get-vhd -path xxx.vhdx | select diskidentifier). Rubric backup fails when it sees identical diskidentifier, maybe other backup apps too. Is this a new "feature"? Older VMs seem to have unique diskID. Is there a way to prevent this behaviour? Or can it only be fixed it afterwards with "set-vhd -ResetDiskIdentifier"

Answer 1

Hi,

Yes, you are right. We can reset disk identifier to prevent this behavior using "Set-VHD -ResetDiskIdentifier".

-ResetDiskIdentifier

Indicates that the cmdlet modifies the disk identifier of the virtual disk associated with the virtual hard disk file. The disk identifier is the SCSI Vital Product Data (VPD) Page 0x83h identifier associated with a disk. Use this parameter only for a VHDX-format disk.

https://learn.microsoft.com/en-us/powershell/module/hyper-v/set-vhd?view=windowsserver2022-ps