Hi ​@Nikks,

it is generally not necessary to backup the hosts, reinstalling them usually doesn't take very long. If you really want to backup only the C:\ disk I think with Veeam agent there is no problem.

As for Veeam Backup & Replication, it is not recommended to install it directly on the Hyper-V host, better on a VM if you don't have other servers available.

Veeam Backup & Replication must not be installed directly on a Hyper-V host. Such installation may lead to unpredictable system behavior. Instead, create a VM on the host and install Veeam Backup & Replication on the VM.

https://helpcenter.veeam.com/docs/backup/hyperv/installation_byb.html?ver=120

If you need to back up the C drive as noted the agent will do the trick but again as Marco pointed out you should not have Veeam on the host.

I would not put agent or anything on the parent partition of HyperV. Microsoft has explicit instructions not to install anything to parent partition, and even agent backup will heavily disrupt the HyperV operations.

I understand the desire here, but also consider that you’ll effectively be rolling back the HyperV host and very likely there will be many unpredictable things you need to handle even with a successful restore. I’m doubtful that you will be able to do this without re-importing the VMs, and even if you could, there is pretty high chance you’ll need to start backup chains fresh.

Given that, I’m not sure I see the benefit of putting pressure on the HV host and going against Veeam and Microsoft’s recommendations here as opposed to simply reinstalling the OS and importing the VMs, as you’re probably going to end up doing this regardless.

Echoing other’s statements here. If you do not have a spare physical or otherwise separate server to install Veeam on, it would be best to install it on a VM and point it to the Hyper-V host to manage the backups. Hopefully you are in a position where the Hyper-V host is only acting as a hypervisor and not any other service. If so I’d work towards virtualizing those wherever possible.
As a last resort, you could use the Veeam agent to back up the physical server, but that isn’t recommended and you’d certainly want to exclude the VM storage.