New ISO available / ...

Garance A Drosihn drosih at rpi.edu
Sat May 1 21:11:42 PDT 2004


At 7:29 PM -0700 5/1/04, Evan Dower wrote:
Definitely check and make sure that the active flag for your second
partition is set. I had a similar problem after losing and recovering
my partition table. My partition table seemed to be back to normal,
but I couldn't boot from anything but the first slice. After much
hair pulling, I realized that I just forgot to set the active flag
to make them bootable. You'll use fdisk (not disklabel) for this.
Well, that's certainly worth a try.  I tried it, but it didn't help
me.  I still couldn't boot off anything but the first slice (using
the F1 key).
My guess is that it has something to do with what the fdisk man page
describes as:
     The automatic calculation of starting cylinder etc. uses a set
     of figures that represent what the BIOS thinks the geometry
     of the drive is.  These figures are taken from the in-core
     disklabel by default, but fdisk initially gives you an
     opportunity to change them.  This allows you to create a
     bootblock that can work with drives that use geometry
     translation under the BIOS.
It might be that I messed up something there (or maybe GRUB did,
when it was installed).  Perhaps the problem is that the BIOS is
using a different calculation than fdisk on the system is using,
and thus anything that usees the BIOS calls will end up reading
from the wrong part of the disk for everything but the first slice.
(it's safe to assume that I don't really understand the low-level
details of the bootup process...  AND that I don't really want to
learn them, either!   :-)
--
Garance Alistair Drosehn            =   gad at xxxxxxxxxxxxxxxxxxxx
Senior Systems Programmer           or  gad at xxxxxxxxxxx
Rensselaer Polytechnic Institute    or  drosih at xxxxxxx




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