Xen users - Feb 2009 - SCSI driver clash with PV drivers

Hi,

I am trying to boot a DomU system with two harddrives attached as hda
and sda. I can use hda fine as the boot disk, but when I add a second
disk as sda the DomU OS kernel panics on boot.

The DomU is using PV drivers for disk and network access inside a
fully virtualised (qemu-dm) instance. Also, I have disabled replies to
disk probes after the initial DomU BIOS check. This means the
underlying OS shouldn''t be able to see the virtualised disks at all.

I disabled the sd_mod.ko driver inside the domU image and I am able to
boot the DomU in the way I want. Unfortunately it is not possible to
use this work-around in the majority of my planned environment.

I have also been able to get the DomU to boot by specifying the second
disk as xvda instead of sda and this also worked.

I can see plenty of examples of people using ''sda'' as their
device
name, but I cannot make this work for myself.

Any help at all on this would be very welcome.

Thanks,
Iain
-- 
"Just think how stupid the average person is,
and then realize that half of them are even stupider!"
--George Carlin

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Hi,

Given the lack of response to this email, can I just query why?

Did I ask this question in a bad way or is it just that no-one has any
idea how to do what I want?

Thanks,
Iain

On Wed, Feb 25, 2009 at 4:32 PM, Iain J. Watson <iain@ij-watson.co.uk>
wrote:
> Hi,
>
> I am trying to boot a DomU system with two harddrives attached as hda
> and sda. I can use hda fine as the boot disk, but when I add a second
> disk as sda the DomU OS kernel panics on boot.
>
> The DomU is using PV drivers for disk and network access inside a
> fully virtualised (qemu-dm) instance. Also, I have disabled replies to
> disk probes after the initial DomU BIOS check. This means the
> underlying OS shouldn''t be able to see the virtualised disks at
all.
>
> I disabled the sd_mod.ko driver inside the domU image and I am able to
> boot the DomU in the way I want. Unfortunately it is not possible to
> use this work-around in the majority of my planned environment.
>
> I have also been able to get the DomU to boot by specifying the second
> disk as xvda instead of sda and this also worked.
>
> I can see plenty of examples of people using ''sda'' as
their device
> name, but I cannot make this work for myself.
>
> Any help at all on this would be very welcome.
>
> Thanks,
> Iain
> --
> "Just think how stupid the average person is,
> and then realize that half of them are even stupider!"
> --George Carlin
>


-- 
"Just think how stupid the average person is,
and then realize that half of them are even stupider!"
--George Carlin

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

On Sat, Feb 28, 2009 at 3:43 AM, Iain J. Watson <iain@ij-watson.co.uk>
wrote:
> Hi,
>
> Given the lack of response to this email, can I just query why?
>
> Did I ask this question in a bad way or is it just that no-one has any
> idea how to do what I want?

Most likely the later.
If you''re using HVM guest, why bother mapping the disk as sda anyway?
Form what I know so far:
- In windows HVM guest, drives should be mapped as hd[a-d]. Additional
drives can be mapped as xvda, but those extra drives will only be
available when using GPLPV or Redhat''s PV driver.
- In Linux HVM guest it''s somewhat the same. The main difference is
when using the PV driver (I only tested the one in RH), drives will be
mapped twice, as both hda and xvda.

The configs that uses sda that I''ve seen so far is for PV domU.
So back to my first question, is there any need to use sda on your
domU in the first place?

Regards,

Fajar

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

On Sat, Feb 28, 2009 at 3:43 AM, Iain J. Watson <iain@ij-watson.co.uk>
wrote:
> Hi,
>
> Given the lack of response to this email, can I just query why?
>
> Did I ask this question in a bad way or is it just that no-one has any
> idea how to do what I want?

Most likely the later.
If you''re using HVM guest, why bother mapping the disk as sda anyway?
Form what I know so far:
- In windows HVM guest, drives should be mapped as hd[a-d]. Additional
drives can be mapped as xvda, but those extra drives will only be
available when using GPLPV or Redhat''s PV driver.
- In Linux HVM guest it''s somewhat the same. The main difference is
when using the PV driver (I only tested the one in RH), drives will be
mapped twice, as both hda and xvda.

The configs that uses sda that I''ve seen so far is for PV domU.
So back to my first question, is there any need to use sda on your
domU in the first place?

Regards,

Fajar

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Xen-users mailing list
Xen-users@lists.xensource.com
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