Subject: Re: How to write NetBSD boot blocks to DOS disk?
To: Ken Hornstein <kenh@cmf.nrl.navy.mil>
From: Michael L. VanLoon -- HeadCandy.com <michaelv@HeadCandy.com>
List: port-i386
Date: 03/28/1996 19:30:15
>>When I do a "disklabel -B ...", I can boot NetBSD just fine, but it
>>toasts the DOS parition table.  If I boot a DOS floppy and run fdisk
>>after that, it just gives me garbage partition data.

>>My concern is: where does disklable put the boot blocks?  And, where
>>should it be putting them?  Should I maybe start the whole disk in the
>>disklabel at sector one instead of zero, or at cylinder one, instead
>>of zero?  I dunno...

>Hmmmmmmmm ... when you use disklabel -B, do you say "/dev/rsd0c", or
>"/dev/rsd0d"?  What _should_ happen is that the boot blocks should get put
>at the beginning of the NetBSD part of the disk.  If you use /dev/rsd0d,
>it _might_ put them at the beginning of the whole disk.  That would explain
>the problems you're seeing.

Bummer.  I thought this was the answer.  I was using "disklabel -B
... wd0", which uses /dev/rwd0d by default.  So I figured I would
explicitely do "disklable -B ... /dev/rwd0c", but it tells me
disklabel: "/dev/rwd0c: Device not configured".  How can it be not
configured?!  The /dev/ entry is there; the drive is there and probed
successfully on startup.  I don't get it.  I guess you just *can't*
put a disklabel or boot block on the "c" partition.

Any more ideas?  I *know* people have done this (made a single disk
bootable both in DOS and NetBSD).  If you've done it, how did you do
it?

-----------------------------------------------------------------------------
  Michael L. VanLoon                                 michaelv@HeadCandy.com
       --<  Free your mind and your machine -- NetBSD free un*x  >--
     NetBSD working ports: 386+PC, Mac 68k, Amiga, HP300, Sun3, Sun4,
                           DEC PMAX (MIPS), DEC Alpha, PC532
     NetBSD ports in progress: VAX, Atari 68k, others...
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