On Wed, 28 Aug 2002, Joel Baker wrote:

> fdisk -i -c /usr/mdec/mbr_bootsel (configured to boot partition 0 after
> 10 seconds, has an named option for partition 1 as well)
>
> /usr/mdec/installboot /usr/mdec/biosboot.sym /dev/rwd0a
>
> Upon reboot, the boot selector runs, expires the 10 second timer, and at
> that point prints a "3" on the next line, then hangs.

ERR_NOOS -- Magic no. check failed for part.
(from /usr/src/sbin/fdisk/mbr_bootsel/mbr_bootsel.S.)

> Booting from the install CD, interrupting the auto-boot, and entering
> "boot wd0a:/netbsd" works just fine, for both the old and new kernels

Look at "re-installing bootselector ?" thread at
http://mail-index.netbsd.org/port-i386/2001/04/
and maybe at  http://mail-index.netbsd.org/port-i386/2002/05/01/0002.html

   Jeremy C. Reed
   http://bsd.reedmedia.net/