Before you backup and restore Hyper-V virtual machines, ensure that you go through the following considerations.
Considerations for backup and restore of Hyper-V virtual machines
How Druva handles VSS based backup of differencing virtual disks or virtual machines with differencing disks
Druva backs up parent and child disks separately.
When you restore the virtual machine or virtual disks to an alternate location, the parent and child disks are restored separately.
When you restore the virtual machine to the original location, only child disks are restored. The parent disk must be present on the virtual machine or else the restore job fails. You can download the original disk separately and attach it to the virtual machine before you run a restore job.
How Druva handles RCT based backup of differencing virtual disks or virtual machines with differencing disks
Druva backs up and restores the parent and child disks as one consolidated disk.
How Druva handles VSS based backup of virtual machines with shared disks attached to them
Druva cannot run a VSS based backup of a virtual machine with shared disks attached to it and the backup job fails with the error HYPERV53.
How Druva handles RCT based backup of virtual machines with shared disks attached to them
Druva cannot run an RCT based backup of a virtual machine with shared disks attached to it and the backup job fails with the error HYPERV38.
How Druva handles backup and restore operations on Azure hosts
Druva does not support VSS backup and restore operations on Azure hosts with the Azure Stack HCI v21H2 operating system, as virtual machine backups with Volume Shadow Copy Service (VSS) is not applicable on these Azure hosts. For more information, see System Requirements for Hyper-V.