KVM - How to forward RAID correctly?

Question

Virtualization

On the host (debian), a software raid md0 (sda + sdb) was started, a guest system for NAS (Xpenology) was raised using KVM.
I tried to transfer / dev / md0 as a Storage Device, but the guest system only offers to format it.
I tried to transfer / dev / sda and / dev / sdb - the guest system as a whole normally sees hard drives, sees the raid, offered to fix it, but after fixing nothing fell off. But the question arises - how correct is it to transfer /dev/sda - /dev/sdb ? is it possible to pass the array as a single disk?
If you simply transfer both /dev/sda and /dev/sdb disks, is it possible to leave mdadm in monitor mode on the host system?
And how is it guaranteed to prohibit mounting this array in the host system (so that in no case the disks are mounted here and there, because, if I understand correctly, there is a specific risk of screwing up the file system)?

Answer 1

make lvm on the raid and put the system on it

Answer 2

The best option is to simply forward the disks to the VM, and create MD/LVM/ZFS volumes inside.