where KVM is the VM name as listed by `get-vm` commandlet.
This allows VMX CPU extensions to be exposed to the guest.
3) Install QEMU/KVM inside the guest
4) unzip Workstation OVA for ONTAP simulator
5) convert vmdk -> qcow via qemu-img (done on Debian Guest).
6) create VM using virt-manager. This can be also done by importing dupmed XML of an example VM.
7) allowed nested guests in KVM.
Following all these, I succeeded to run 2 instances of ONTAP sim (2 clusters with cluster interconnect). Also Windows and Debian VMs run fine on that KVM hypervisor which itself is actually a guest inside Hyper-V.
Virtualization overhead is almost not noticeable. At least as compared by Linux CLI-based 7-zip benchmark that was executed in first-level guest (VM that runs directly in Hyper-V) and nested guest (debian VM in KVM, while that KVM is a guest in Hyper-V) thanks to VMX extensions exposed all the way through.
KVM configuration and ONTAP xml of the KVM guest (domain) can be found in this thread: