Re: [9fans] PXE boot?

[andrey mirtchovski <mirtchov@cpsc.ucalgary.ca>]

On Fri, 30 May 2003, David Presotto wrote:

> The 32k limitation doesn't seem to be true.  The limitiation is architecture
> dependent and the PC seems to have chosen infinite, though there is a
> practical limit of (640-28)K because of where things get loaded.  I've
> got 9load saying hello but it crashes when it jumps to 32 bit mode.
> My forehead is getting bloodier by the minute.
>

i'm there too. i gave up though -- etherboot won't recognize the gigabit
ethernet card on this box, so i'm waiting until i get a card etherboot can
use.

another suggestion: why not do a three-stage boot? the dhcp configuration for
etherboot (linux dhcp, though, not sure if supported in plan9) has this
interesting option:

        if substring (option vendor-class-identifier, 0, 9) = "PXEClient" {
            filename "/tftpboot/etherboot";
        } else {
            filename "/tftpboot/9load";
        }

the first time it loads the etherboot kernel, which then repeats the same
operation, but is this time given a 9load, which is masked as a linux kernel
image (this is what Ron uses to boot the small solid-state cluster). then
9load could proceed loading any way it likes (still no plan9.ini at this
point, though). this way there is no restriction on the size of the 9load
image.

I can't test this right now, unfortunately.

andrey

ps: i'm aiming for an even better setup -- PXE downloads etherboot through
the gige card, etherboot downloads 9load through a 100baseT rtl card i've
stuck in the machine just for that purpose, 9load does something else that i
haven't decided upon yet.