[one-users] Strange behaviour of DEFAULT_DEVICE_PREFIX and TARGET when using Xen in HVM mode

[Tino Vazquez]

Hi,

So then, if you set the DEV_PREFIX to xvd, everything should work as
expected, right? I mean, you would end up with a deployment file like
the one you just modified.

Take into account that you can set TARGET in the image template, and
also force it in the DISK section of the VM template.

Regards,

-Tino

--
Constantino Vázquez Blanco, MSc
OpenNebula Major Contributor
www.OpenNebula.org | @tinova79



On Thu, Sep 1, 2011 at 10:34 AM, Maxence Dunnewind
<maxence.dunnewind at inria.fr> wrote:
> Hi Tino,
>
>> Not sure why that is the case. To use /dev/xvd* devices in Xen, domU's
>> need to load the xen paravirtualization kernel modules.
>>
>> Maybe loading these drivers as explained in [1] helps?
>
> I tried loading these modules without result, the datablock still does not
> appear.
>
> Anyway, if I change the deployment.0 to replace xvde by xvdc, so it looks like :
>
> ===
> name = 'one-1956-2'
> #O CPU_CREDITS = 256
> memory  = '256'
> kernel = '/usr/lib/xen-default/boot/hvmloader'
> disk = [
>    'tap:aio:/srv/cloud/one/var/1956/images/disk.0,xvda,w',
>    'tap:aio:/srv/cloud/one/var/1956/images/disk.1,xvdc,w',
>    'tap:aio:/srv/cloud/one/var/1956/images/disk.2,xvdb,r',
>    ]
> vif = [
>    ' mac=02:00:83:fe:cc:a3,ip=131.254.204.163,bridge=eth0',
> ]
> builder='hvm'
> device_model='/usr/lib/xen-default/bin/qemu-dm'
> vfb = [ 'type=vnc' ]
> ====
>
> Then it works, the disk is correctly detected ( as /dev/sdc ).
>
> I tried many values, works for xvdc & xvdd, does not work for xvde and above
> (always shown as sdc).
>
> Maxence
> --
> Maxence Dunnewind
> System Engineer on Bonfire
> Research Center INRIA Rennes - Bretagne Atlantique, France
> Team Myriads, Office E219, tel +33 2 99 84 25 76
>