Hi,

Andy Ball wrote:
> The root partition is within the first 1024 cylinders (even
> though the 'BIOS-level partition' it's in is not entirely. I
> don't know if the firmware of the machine I'm using makes a
> difference.

Note the different concepts of cylinders here!

Leaving out newer BIOSes for now (but see below), it is only required
that the root partition is within the first 1024 cylinders as defined
by the BIOS geometry.  This restriction is a result of the use of
the BIOS to boot the machine.  It isn't needed to be within the first
1024 cylinders of the NetBSD geometry nor of the real geometry
(if you would even be able to get at that one).

>   GF> The actual limit depends on the BIOS.. on newer
>     > BIOSes, I think you can have it anywhere within the
>     > first 8 gigabytes.
> 
> Didn't I just say that? ;-)  I needn't worry about the 8Gb
> barrier on this machine yet... it only has a 1.7Gb drive.
> Perhaps it's another reason to be wary of ATA drives.  I'm
> using what I have to hand.

No, on newer BIOSes which happen to (correctly!) implement the
int13-extensions there is no limit at all for the placement of
the root partition.

The 8GB limit is the result of the maximum geometry supported by
the old int13 code being 63 sectors/track * 255 heads * 1024 cyls.
If you multiply this out (and keep in mind that the sector size
is 512 bytes), you end up with just a bit below 8GB.

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