[1408] in netbsd-help mailing list archive
Re: access to DOS ext. partition
daemon@ATHENA.MIT.EDU (Greg Hudson)
Tue Feb 16 15:53:47 1999
To: Robert J Fleming <bfleming@MIT.EDU>
Cc: netbsd-help@MIT.EDU
In-Reply-To: Your message of "Tue, 16 Feb 1999 15:34:46 EST."
<199902162034.PAA00955@uqbar.mit.edu>
Date: Tue, 16 Feb 1999 15:53:20 EST
From: Greg Hudson <ghudson@MIT.EDU>
The disklabel geometry does not have to be the same as your BIOS
geometry and, due to some issues with the existing FFS code, doesn't
usually want to be. In your case (which is the usual case), the
disklabel geometry reflects the geometry reported by the disk, whereas
the BIOS geometry is translated to get the number of cylinders down to
under 1024.
To make your DOS partition accessible you want to use disklabel -e to
edit your disklabel. You'll need to know the size in sectors of your
logical DOS partition and it's starting sector relative to the
beginning of the disk (many partitioning utilities will report where
it is relative to the beginning of the extended partition). The
NetBSD fdisk can't tell you that, so you'll have to find out using
pfdisk or the DOS fdisk or something, and maybe do some math. Use the
BIOS geometry (993/128/63) to do any based on cylinder numbers in the
MBR.
I hope this helps.
