[Beowulf] deciding what partition to boot from on XP boxen

[Jakob Oestergaard]

On Mon, Dec 12, 2005 at 07:13:23AM -0500, Alpay Kasal wrote:
...
> My issue: I'd like to do what I think RGB is describing below. I'd like to
> have 2 partitions on local drives in the nodes, one containing winXP and one
> containing the imaging software. Can I boot nodes via PXE to make the
> decision of which local partition to boot from?

Using PXELINUX for PXE boots you can select on the boot server on a
per-client basis whether the client should boot from local disk or from
the network.

I used this in a compile farm once; I had several machines that would
always PXE boot. Depending on what needed to be done, the system would
either network-boot a small Linux image which would re-image a specific
OS image on the local disk, then reboot. The PXE config for that node
would then select local-disk boot.

So, that way I ran FreeBSD, Linux, Windows and other funny things in
seemingly (to the OS) standard local-disk single-boot configurations.
Only one OS at a time on a machine.

When the job was done on whatever-the-OS-of-the-hour, it would reboot
and by then the PXE server would have changed the config so that the
system booted the network-booted Linux based imaging system that would
then be ready to re-image another 'native' OS onto the client.

I thought it would be great for blades. But in the end it ended up being
cheaper and faster to run the various OSes in vmware and have a queue
system spawm vmware instances on a farm of larger machines.


Ugh... I hope that, well, somehow, the concept of what I did is somewhat
clear  ;)

> Should I be looking towards
> making changes to grub via scripting instead? The reason for me to create a
> new workflow is because Acronis' PXE method can be unreliable, I've been
> using boot cd's lately.

Well, the short answer is that with the PXELINUX boot loader you can
boot from any local-disk partition you like, so having multiple
'operating systems' (XP and Acronis I guess in your case) on a local
disk and selecting which to boot by means of PXE is entirely possible.

The not-so-short answer is that you can even kick out Acronis, at least
as far as I understand from your description, and replace it with a
NFS-root network booted linux image that does nothing but re-image your
XP and reboot.  It is, as I understand it, just a simpler setup than
what I hacked together with a colleague over a weekend (we had a
PostgreSQL backend for image/host configurations as not all hosts could
run all images, web front end for management and queue system for
actually scheduling the various OS-bound jobs).

How much of the above that would make sense in your setup, well, I guess
that's something only you can decide.  :)

-- 

 / jakob