[fedora-virt] Guest can no longer be bootet with libvirt 0.9.6 from virt-preview repo

[Ruben Kerkhof]

On Wed, Sep 28, 2011 at 16:12, Dennis Jacobfeuerborn
<dennisml at conversis.de> wrote:
> On 09/28/2011 01:23 PM, Ruben Kerkhof wrote:
>>
>> Hey Dennis,
>>
>> On Tue, Sep 27, 2011 at 16:20, Dennis Jacobfeuerborn
>> <dennisml at conversis.de>  wrote:
>>>
>>> Hi,
>>> I just noticed that once I upgrade to libvirt-0.9.6-1 from the
>>> virt-preview
>>> repo on my Fedora 15 machine I can no longer boot guests that use virtio
>>> disks. I only get "Boot failed: could not read the boot disk".
>>> Removing the disk and re-adding it as IDE drive allows KVM to boot from
>>> the
>>> disk (although the full boot obviously fails due to the hda/vda naming
>>> difference but that's expected).
>>>
>>> After downgrading to libvirt-0.8.8-7 again the problem goes away and the
>>> guest boot fine from virtio disks.
>>>
>>> Is this a known problem? Do I have to configure something differently to
>>> make this work as it should?
>>
>> What version of Seabios are you using? I believe support for direct
>> booting from virtio disks was added only recently.
>
> That can't be right. I've been using only virtio disks for years now and
> never had any problem booting from them.
> Also as I mentioned above it is upgrading/downgrading libvirt that
> creates/fixes the issue. I don't touch the installed seabios package at all.
>
> Regards,
>  Dennis

Somewhere around 0.9.4 libvirt switched to use a different method to
indicate from which device to boot.
See http://libvirt.org/git/?p=libvirt.git;a=commit;h=c3068d4d2381146ed46051ad636a928edea5c602

I think this causes Seabios to skip using extboot.bin for booting and
to try to directly boot from a disk.
If your Seabios version is too old, it won't support booting from
virtio disks directly.

Does adding <bootmenu enable='yes'/> to your xml help? If I'm right
this will cause Seabios to fall back to using extboot.bin

This is all just a wild guess, but I'm having the same issue with scsi disks.

Regards,

Ruben