[Beowulf] BIOS

Carsten Aulbert carsten.aulbert at aei.mpg.de
Mon Aug 13 00:21:01 PDT 2007

John Hearns wrote:
> I would advise the original poster to read up on /dev/nvram - capture
> the /dev/nvram of a 'good' node in a file. Update a node via PXE, then
> when it is rebooted into Linux use cat goodfile > /dev/nvram
> A forlorn hope really.

The trouble with this is simply, that some modern BIOS store more
information than others, especially in areas not accessible by
/dev/nvram. SuperMicro has a few boards storing 256 byte(?) instead of
he allowed 114 bytes. Also, at least in some of their A-series boards
they seem to store the date of the last flash (or something related),
thus even hacking the kernel module to read more data would not help
much, since the md5 hash of each image will differ anyway. Thus one
would have to reverse engineer where what is stored... quite a hassle.



More information about the Beowulf mailing list