Subject: Re: Problems with dual booting
To: None <atatat@atatdot.net, reinoud@ibbnet.org>
From: Wolfgang Solfrank <ws@tools.de>
List: netbsd-help
Date: 04/03/2000 16:02:06
Hi,

> I believe the issue is the following:
> The bios os a x86 platform can read on till cilinder 1023 from a disk.
> Now for linux and the bsd's this isnt a problem, however, the freebsd bootloader and lilo use the bios to read the kernel from a disk. So both cant boot os'ses from parts of a disk where the bios cant reach it. In this case, just use the netbsd bootmanager, it's a great thing and easy to install, i guess that'll solve your problem. 

Slight correction/addition:

The bios on newer PCs can access a disk with two methods.  For compatibility,
it supports the old method with its 1024 cylinder limitation.  The newer
method allows access to much larger disks (I'd have to look it up again,
if you need to know the exact number, but believe me, there is quite some
room left, even with todays rapidly growing disk sizes).

The netbsd bootmanager (as well as the standard netbsd mbr, and the netbsd
partition bootcode) does use the bios to read the kernel from disk, just as
its linux/freebsd counterparts.  It does however try to use the newer method,
it it determines that the old method wouldn't work.  Thus it is able to
boot from partitions beyond the 8GB limit.

Ciao,
Wolfgang
-- 
ws@TooLs.DE     Wolfgang Solfrank, TooLs GmbH 	+49-228-985800