Restore an Azure VM with the existing VM still running

Question

I have a VM that has an Windows Update issue.

I want to restore the Azure managed disk to about 1 month ago to see if this issue was there at that point.

I don’t want to affect the original VM because its still working ok apart from the update problem.
What is the best way to do this?

The disk has Azure Disk Encryption on it and is domain joined.

I can restore the disk and create a new VM from it (with a different Azure name), add into a different subnet – but this will still start it up with the same internal computer name/guids/domain join as the existing. I don't care about logging into the domain on the test VM once restored - i just need local access.
But I would like both VM’s to be up at the same time.

What is the best way to isolate this “test recovered VM” so it does not have any impact on the existing server?
I thought about recovering the disk and then moving it to a different subscription then creating the VM from the disk after its been moved but that wont work due to the encryption on it needing to communicate with the Keyvault to decrypt.

Is there a good way to do this?
Thanks!

Answer 1

Restoring the VM in a different Virtual Network (with a different subnet) may work. Just be sure there is no peering activated between the two virtual networks.

Subnets in the same Virtual Network are routed automatically. But 2 Virtual Networks are not "connected" if you don't activate the peering.

Maybe this is helpful.

Regards

Andreas Baumgarten

(Please don't forget to Accept as answer if the reply is helpful)

Answer 2

I don't have another vnet - but I could certainly create one. The separate VNet wont have access to our AD either so that prevents any weirdness with 2 computers using the same account, and it would have access to the Keyvault to decrypt the disk when starting up.

I shall try that.
Thanks.