[ILUG] Xen, Debian on DELL PowerEdge 2850[Scanned]

[Peter McEvoy]

On Thu, Oct 05, 2006 at 01:56:25PM +0100, Cormac McClean wrote:
> I teach a course in Linux System Administration. Each year I set up 
> multiple virtual servers so that
> students can have root access to their own system to learn essential skills.
> 
> This year I have been provided with a DELL PowerEdge 2850 server, 
> replacing older hardware
> which wasn't up to the job. I'm now trying to setup Xen on Debian (Sarge).
> 
> However, I am running into serious problems, which I believe are due to 
> the SATA hard drives in the DELL.
> For example, the standard Debian install iso will not work - it doesn't 
> recognise the hard drives.
> I have had to use custom built isos (e.g. from 
> http://blog.blackdown.de/2005/06/26/debian-installer-with-kernel-2611/) 
> to install a basic Debian system.

The debian etch installer should work fine on that hardware, obviously
the usual caveats of lack of security/not 100% tested packages/etc apply 
- but I find etch or sid perfectly manageable for a dom0 with nothing
but ssh and the xen packages installed

> I have built a xen-patched kernel (as described in 
> http://julien.danjou.info/xen.html) configured to include SCSI_SATA and 
> SCSI_ATA_PIIX (which Googling has led me to believe might solve the 
> problem), and added the appropriate lines to my grub/menu.lst:
> title Xen 3.0 / XenLinux 2.6
> kernel /boot/xen-3.0-i386.gz
> module /boot/xenu-linux-2.6.16.19-xen root=/dev/sda1 ro

You would need to an another module line pointing to the initrd which
contains the requisite support for your hardware.
My experience is the debian packaged kernels work well for poweredges,
so apt-get install linux-image-2.6.16-2-xen-686 should provide a working
kernel for dom0 and domU. You'll probably have to generate the initrd
yourself - mkinitrd is deprecated now so using mkinitramfs or yaird
would be better options.
Its also worth pointing out theres an issue with 2.6.17 debian xen
kernels - it will kernel panic after you start your third domU, which is
why I would recommend 2.6.16-2

I gave a demo to to Belfast linux user group last week, this is the
command history of what I did:

http://yerma.org/~pete/temp/talk.txt

(the order of commands is slightly off kilter, but you should get the
idea)

Cheers

-- 
Pete