[CentOS-virt] Vmware Server 2 and KVM....

Tue Aug 17 16:56:54 UTC 2010
Pasi Kärkkäinen <pasik at iki.fi>

On Tue, Aug 17, 2010 at 09:35:24AM +0100, James Hogarth wrote:
> >
> > Uh.. are you mixing Xen and KVM now?
> >
> > I think KVM *always* requires the kernel module, aka CPU support for hardware virtualization.
> >
> > -- Pasi
> >
> You might be right... having trouble googling something... but I
> thought that kvm without -enable-kvm (or with -no-kvm) and with
> -kernel, -append and -initrd specified could be used for a
> paravirtualized guest .... However that might just be fully emulated
> on qemu which might or might not help rather than
> paravirtualization...

Without KVM Qemu runs everything on pure software, 
so it's still full virtualization, but damn slow.

> My apologies if I err ^^ been a while since I had a system without
> available an vmx/svm interface on the CPU....
> I know for a fact that libvirt doesn't support PV guests under KVM...
> virt-install (which uses libvirt) will refuse to try it etc.

Yeah, because PV guests are *Xen* guests. 
To run PV guests you need to be running Xen hypervisor.

> I'll test it later this week to satisfy my curiosity ;)

"Xenner" is a separate tool that is able to run some Xen PV guests on KVM,
but it's experimental and it's not developed anymore.

Xenner requires KVM, and thus CPU virtualization extensions.

Only way to run Xen PV guests on a hardware without CPU virtualization support
is to actually use Xen hypervisor :)

-- Pasi