What are the advantages of using the Hyper V Ahsay module over a straight backup of my VHS files online? The module costs money, but a simple backup doesn’t have a license charge. We are using SVR 2016
Hi
Hyper-V module
The Hyper-V module will back up the virtual environment, including vNICs, vCPU, and other resources. This will allow you to restore the complete VM and its environment back to the host server. One stop for everything.
The Hyper-V module costs can be found here Instant cloud backup price calculator
The Hyper-V module will also back up AVHDX files created during the backup on Windows 2012 and later. Hyper-V creates these files during the backup.
This was a change in Windows Server 2012, when Microsoft stopped using VSS to back up VMs and began using an in-built Hyper-V backup. This is the same process as Hyper-V snapshots.
This approach improves data integrity and streamlines the backup \ restore processes. This will also incur an additional cost for the backup, as AVHDX files are created and backed up. Considering the benefits, this extra cost is negligible.
Basic VHD(X) file copy
You can easily back up these files through a simple file system backup. They are backed up in real time and, in effect, grab the disks at a given moment. When you restore, the VM will appear to have crashed (blue-screened) and then boot normally.
Because the underlying VM doesn’t know it is being backed up, it can’t prepare for it. We haven’t encountered any issues with this backup method in our introductory lab, but you should run your own restore tests periodically.
With more complex VMs, i.e. those running Exchange and busy databases, you will need to consider whether all transactions are safe from corruption.
DR process
Hyper V module
If the Hyper-V host server needs to be rebuilt, it must be rebuilt the same way as the original before the VM can be restored, i.e., with the same name, Active Directory membership, and virtual network.
Basic VHD(X) file copy
You can restore the VHD(X) files to any Hyper-V host server and manually recreate the virtual environment. Version control considerations need to be taken into account; for example, you can’t restore a Windows 2016 VM to a Windows 2008 Hyper-V host.
It is unlikely to happen, though, because you will probably create a new Hyper-V host during DR.
The virtual environment can be recreated manually, though not easily. You will need to set the VM type correctly (Gen1 or Gen2). If you take a few screenshots of the VM’s config beforehand and update them when you make changes, that will be sufficient.
The question you asked is somewhat open-ended, and we can advise much better if we know more about your environment. If you don’t know about Hyper-V replication (no shared storage), it is a great preventive measure against a single-server failure.
We can assist in setting this up on Azure or another server of yours, should you require it.
