KVM Host --W10 VM with HYPER -V running another VM (Nesting)

Hi there.

It seems some CPU's will handle HYPER-V in a VM running on a Host where a HYPERVISOR (KVM in this case) is already running.
One needs to make a few mods otherwise booting up the VM running UNDER the HYPER-V (the 2nd level VM) will freeze.

I'm currently playing with this -- it looks like some modules from QEMU need to be updated -- and one needs to use IOMMU to get any sort of decent I/O throughput - even on SSD's.

I'll post back when I've got some better results -- note I haven't a CLUE about AMD CPU's . I think also getting USB and SOUND on to the second level VM could be a problem. PCI passthru is pretty easy from the KVM Host to the Windows VM (ist level) but passing that to the second level VM is proving somewhat problematical.

(HOST --CENTOS 7 with KVM, ist level VM W10 pro with HYPER-V enabled, second level VM W7 ultimate -- all x-64 machines).

I believe also performance can be improved by switching from Full virtualisation to "Para virtualision" on the guests -- easily enough done with settings in KVM - but then passthru gets a bit ????.

Anyway I've got some time to play with all this --when I'm done I'll post a guide. It should work also for most other common Linux distros capable of running KVM.

Tip - don't use the libvirt manager GUI as a console for your VM's as once in Full screen you can't always get back to Windowed mode -- might be my mouse etc. Use RDP / VNC instead -- no problem connecting to VM's even if you are running the VM's on your local machine.

Cheers
jimbo

Hi.

I'll be trying something similar out.
With Hyper-V on Ubuntu 14.04
Need some help to get it working.

Can you please mention the modifications/updations that are needed?
The guide would be really helpful.

Thanks,
indu.

indu119 said:

Hi.

I'll be trying something similar out.
With Hyper-V on Ubuntu 14.04
Need some help to get it working.

Can you please mention the modifications/updations that are needed?
The guide would be really helpful.

Thanks,
indu.

Hi there

I'll have a go with this over the weekend -- not doing much else this weekend so I've got a bit of time.
It should work on UBUNTU as well -- note enable VTX on your CPU or it won't work.

Cheers
jimbo

Hi,

I would be interested in your guide too.

I have KVM with nested virtualization enabled running on Ubuntu 14.04, and a Windows Server 2012 R2 guest.
But in the guest, the command line

Code:

wmic cpu get VirtualizationFirmwareEnabled

returns false

Thanks.

Hi,

I would also like to try this on Ubuntu 14.04
Can you please let me know how to get it working.
You mentioned that some modules of QEMU needs to be updated.
Any details on how to get this working will be helpful

Regards,
Sagar

jimbo45 said:

Hi there.

It seems some CPU's will handle HYPER-V in a VM running on a Host where a HYPERVISOR (KVM in this case) is already running.
One needs to make a few mods otherwise booting up the VM running UNDER the HYPER-V (the 2nd level VM) will freeze.

I'm currently playing with this -- it looks like some modules from QEMU need to be updated -- and one needs to use IOMMU to get any sort of decent I/O throughput - even on SSD's.

I'll post back when I've got some better results -- note I haven't a CLUE about AMD CPU's . I think also getting USB and SOUND on to the second level VM could be a problem. PCI passthru is pretty easy from the KVM Host to the Windows VM (ist level) but passing that to the second level VM is proving somewhat problematical.

(HOST --CENTOS 7 with KVM, ist level VM W10 pro with HYPER-V enabled, second level VM W7 ultimate -- all x-64 machines).

I believe also performance can be improved by switching from Full virtualisation to "Para virtualision" on the guests -- easily enough done with settings in KVM - but then passthru gets a bit ????.

Anyway I've got some time to play with all this --when I'm done I'll post a guide. It should work also for most other common Linux distros capable of running KVM.

Tip - don't use the libvirt manager GUI as a console for your VM's as once in Full screen you can't always get back to Windowed mode -- might be my mouse etc. Use RDP / VNC instead -- no problem connecting to VM's even if you are running the VM's on your local machine.

Cheers
jimbo