The following reply was made to PR install/31274; it has been noted by GNATS.

From: David Laight <david@l8s.co.uk>
To: Pavel Cahyna <pavel.cahyna@st.mff.cuni.cz>
Cc: gnats-bugs@NetBSD.org
Subject: Re: install/31274: can't install with single large partition easily, sysinst menu is inconsistent
Date: Sun, 23 Oct 2005 10:10:41 +0100

 On Sat, Oct 22, 2005 at 10:36:51PM +0200, pcah8322@artax.karlin.mff.cuni.cz wrote:
 > I'm almost sure that the BIOS can access the whole 18 GB disk, as Windows
 > NT (2000) were installed in a single large FAT32 partition, so their
 > bootloader had to be able to access the whole disk (unless they do some
 > dirty trick like putting the kernel and all LKMs in the beginning of the
 > filesystem, which I strongly doubt).
 
 The FAT (and NTFS for that matter) filesystems tend to fill up the disk
 from low sector numbers.  So the boot code could easily all be in low
 sector numbers!  (This is why they need 'defragmenting', and more or less
 what defragmenting does.)
 
 > The machine is Compaq Evo N600c laptop with 1 GHz Pentium III CPU and I
 > think it's "new enough".
 
 What does 'sysctl machdep.diskinfo' report?
 My guess is 80:39070080(1022/240/63),0 wd0:80
 The ',0' indicates that LBA reads aren't (being reported as) supported.
 
 > But the BIOS is probably a bit strange. fdisk says:
 ...
 > BIOS disk geometry:
 > cylinders: 1022, heads: 240, sectors/track: 63 (15120 sectors/cylinder)
 > total sectors: 39070080
 ...
 > the "heads" value looks nonstandard and the BIOS already confused GNU
 > Parted, which made NT unbootable by setting the geometry values in their
 > boot sector to different values when shrinking the partition.
 
 It is certainly more usual to use 1024 cylinders and 255 heads for the
 facked geometry.  But other values are used.
 Possibly the BIOS has some options for that disk - like 'LARGE', LBA' etc
 the different ones will give different faked geometries.
 
 > Also, why did sysinst offer to create circa 0.5 GB root? The NetBSD
 > partition starts at ~ 5 GB, and 5.5 GB is not near any BIOS or IDE magic
 > limit IIRC.
 
 sysint has default sizes for / and /usr (which are horridly out of date)
 which are, hopefully,  just about big enough for a simple install.
 It will try hard to stop you making parts of / unreadablt by the BIOS.
 
 At least you get a chance to change the default sizes these days!
 
 
 	David
 
 --
 David Laight: david@l8s.co.uk