[Users] booting a vm on a raw file disk definated in a hook script

[Shahar Havivi]

On 01.06.12 17:40, Itamar Heim wrote:
> On 05/25/2012 05:47 PM, Nathanaël Blanchet wrote:
> >Hi all,
> >
> >I'm using this hook script :
> >http://gerrit.ovirt.org/gitweb?p=vdsm.git;a=blob;f=vdsm_hooks/vmdisk/before_vm_start.py;h=191d5c1af533e11d699b1d715d3c1ea60e28b787;hb=6817f1c6e3f5bc137d1f3bef45a2d0191465c7a3
> >My goal is to boot a vm on a vm image imported form libvirt/kvm. I want
> >to use this single image, that is to say without importing it into ovirt
> >with tools like v2v.
> >acathrow told me on irc that I'd have to change the boot order in the
> >xml, but I don't know how to proceed for many reasons:
> >
> >  * I can't create a vm through the UI which would boot on the disk
> >    created by the hook script without first creating a disk on the
> >    relevant storage domain. If I try I have those warnings :
> >
> >    hook: Cannot run VM without at least one bootable disk.
> >    Alternatives:
> >    -Create a disk for this VM, and rerun the VM.
> >    -Change the boot sequence using the Edit VM command (Boot Option
> >    Sub-Tab).
> >    -Use the Run-Once command to select a different boot option and
> >    rerun the VM.
> >  * If I run a vm with the first disk from the storage domain and an
> >    additional disk from the hook script, how could I change the boot
> >    order in the xml definition file if I don't know the xml definition
> >    of the main disk?
> >
> >
> >thanks all for your help
> 
> 1. i guess you can change the script to fix the boot order.
> 2. you can create a VM with a disk the same size, and just copy your
> converted disk over it (cp for nfs, dd for iscsi), instead of using
> the hook.
Today you cannot do that because the hook didn't designed to do that.
By modifying the hook you can add a <boot order='1'/> to the disk and change
the other device boot order to higher number.

Take a look at this links:
http://libvirt.org/formatdomain.html#elementsDisks
http://libvirt.org/formatdomain.html#elementsNICSBoot
and look for the string 'boot order'