Hyper-V and "Event ID: 58 – The disk signature of disk 2 is equal to the disk signature of disk 0"

On Monday I talked about how we had changed backup in Windows Server 2012 R2 to make it scale better.  However, there is one annoying downside of this change that I did not discuss.  And that is Event ID 58.

As I mentioned – we now connect a copy of a virtual machines virtual hard disk back to itself in order to revert to the correct VSS snapshot.  When this happens – the copy of Windows running inside the virtual machine sees two hard disks with exactly the same disk signature.  In the real world – this is something that should never happen.  And the result is that the guest operating system will log a warning event (Event ID 58) that states that it has found two disks with the same signature (and that it is confused, scared and afraid).

Fortunately, this warning message can be safely ignored in this instance.  Unfortunately, it cannot be suppressed.

Cheers,
Ben