Nested Virtualization – oVirt Node 3.2


The sky is the limit!!!

What was just an idea not so long ago has turned into realty.
Thanks to the efforts of the oVirt devs it is now possible to virtualize an oVirt node, adding another virtualization layer.
Obviously the first step is to install oVirt Engine 3.2 on Fedora 18 thru the official oVirt repositories.
Then we add a Fedora 18 node – actually two in our case - with a properly configured vdsm daemon, joined by the vdsm-hook-nestedvt.noarch package which is actually the one that makes this little black magic trick work. Don't forget to enable the KVM nested virtualization itself by putting "options kvm-intel nested=1" inside the /etc/modprobe.d/kvm-intel.conf file on the node (that's for an intel arch, of course). Finally, have the node join the engine.

We're now ready to virtualize a shiny new node inside a V.M. which, in turn, is virtualization capable. We'll let it join the very same engine.

Here are the main packages involved in this experiment:

Kernel: 3.7.9 – 201.fc18.x86_64
Libvirt: libvirt-
Vdsm: vdsm-4.10.3-8.fc18

This is just a demo of the kind of power nested virtualization unlocks.

Have a few screenshots and thanks for taking time to read this.

Physical and Virtual Hosts:

 Virtual Machines

Virtualized Host

V.M.s running on a Virtualized Host

Davide Giannilivigni 
Daniele Pavia