[gPXE] generic boot standard virtual drives: interesting and implementable idea?

[Paul Geraedts]

Hi all,

Today I got an idea that I believe is interesting to share with this
mailing list.

A couple days ago I watched your LinuxCon presentation, in which Marty
mentioned that there are some initiatives to reach a more standarized
way of hand-off AoE and iSCSI drives to Linux distributions somewhere
during the initrd process. If you ask me, being able to using these
kind of drives in a fully transparent way without requiring user
intervention would simply rock! : )

Today I made a link between this idea and a post on Marco Gerards blog
that I read recently. (Although we share almost the same last name, we
have no family relation as far as I know; probably he's also from
Holland or maybe from Belgium.) Anyway, this guy has been pretty
active in the development of GRUB2. Among other things, he added the
'loopback' command to GRUB2 with which you can mount things like ISOs
or floppy images. Being able to boot from the El Torito or MBR/VBR
part of an image is definitely a great feature. Unfortunately though,
this loopback command has the same hand-off limitation as AoE or
iSCSI: the dream ends at the BusyBox prompt..

So my idea: wouldn't it be a great idea to not only 'standarize' the
way AoE and iSCSI drives hand-off, but include virtual drives in
general in such a hand-off protocol (including floppy, CD, DVD, etc.)?
So roughly something like that all the bootloader stages look for this
'virtual drive list' (in low memory?) and that they add their own
virtual drives (in a linked-list fashion?) to this list, in addition
to them hooking these virtual drives in the INT13 interrupt. Then you
could do things like booting a virtual machine from a virtual live CD
that's located at the other side of the world as if the CD would be
inside your optical disc drive, fully transparently and without any
user intervention! Not to mention putting back the good old floppy and
DVD drives to netbooks; i.e. who cares that they are virtual if they
act as the really thing.. (I would almost suggest to play their
comforting sound during accessing, but I guess I'm getting carried
away too much now ; ).

I'm an electrical engineer myself, so no expert on hardcore low-level
implementations of such an idea. One of you is certainly better able
to judge on this implementation side. I would be really interested in
any feedback on this.

Cheers,

Paul


P.S. Here's is the link to the Marco Gerards post that I mentioned:
http://mgerards.net/blog/?p=16
        (When I think about it, it could be an idea to send a
reference to this gPXE thread to Marco or to a GRUB2 mailing list.)