Subject: Re: NetBSD-2.0 Install CD does not boot on Dell
To: None <port-i386@netbsd.org>
From: Wolfgang S. Rupprecht <wolfgang+gnus20041221T093914@dailyplanet.dontspam.wsrcc.com>
List: port-i386
Date: 12/21/2004 10:47:18
martin@duskware.de (Martin Husemann) writes:
> On Tue, Dec 21, 2004 at 03:35:38PM +0100, Feico Dillema wrote:
>> The problem is (I think) that the BIOS does not even manahe to load the bootloader
>> from the CD. Beofre getting the bootloader prompt, the BIOS prints DISKERR on the
>> screen and that's it (I first thought the CD was badly burned, but the CD is just
>> fine).
>
> We could argue that your broken BIOS is not NetBSD's fault ;-)

If it turns out that this is indeed a cdrom/floppy emulation problem
it might be interesting to note if a direct style cdrom bootstrap
works better.  The new machines designed to run recent microsoft code
don't really need that emulation code, so we might start seeing more
and more bioses not have it.

I believe both {free,open}bsd do non-floppy emulated cdrom boots now.
What they now do is have a 2048-byte bootstrap (called cdbr) that gets
placed on the CD via "mkhybrid -b cdbr ...".  That bootstrap knows how
to read the second-level bootstrap (cdboot) from the root of the cdrom
iso filesystem.  Similarly that second level bootstrap reads the
kernel from the root of the iso fs also.

(I always hated the way the floppy emulation hides the running
kernel's binary away from prying eyes.  You can seriously confuse
yourself by having a different kernel in / on your cdrom from what
your loaded via the emulation area.)

-wolfgang