Subject: Re: Large Disks / Clean Install
To: Manuel Bouyer <bouyer@antioche.lip6.fr>
From: None <mcr@solidum.com>
List: current-users
Date: 01/29/1999 11:27:36
>>>>> "Manuel" == Manuel Bouyer <bouyer@antioche.lip6.fr> writes:
    Manuel> On Jan 28, Paul Wain wrote
    >>  wd0 at wdc0 channel 0 drive 0: <Maxtor 91728D8> wd0: drive
    >> supports 16-sector pio transfers, lba addressing wd0: 16479MB,
    >> 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 33750864 sectors
    >> wd0: 32-bits data port wd0: drive supports PIO mode 4, DMA mode
    >> 2, Ultra-DMA mode 2
    >> 
    >> Now look at that carefully. 16.5 Gb disk, sounds fine. However
    >> 16383*16*63*512 => ~8.2Gb disk! Where has all the rest
    >> gone. Looked on the drive case. 16383*16*63. So the drive
    >> probed co

    Manuel> Known brockennes of the current i386 BIOS: it's limited to
    Manuel> 16383 * 16 * 63 (which means you can't boot from a
    Manuel> partition after the 8G limit).  The current ATA draft
    Manuel> specifies that disk bigger than 8G shoun'nt report a CHS
    Manuel> bigger than this, to not confuse the BIOS.

  Hmm. I have a 10Gb drive with Linux on it. It worked fine on a
K6/266 ATX system, but was intended to go on our fileserver, a K6/200
AT system. The AT system definitely got 19k/16/63 as parameters, and
this royally messed up LILO. The ATX system got the same things and it
didn't care.... so there is some kind of support in newer BIOSes for
larger disks. I don't quite get it.
  What pissed me off, and resulting n us leaving a 3Gb disk in as the
boot disk was that even if I told the BIOS that I had 1024/63/256
(instead of 1244/63/256) that it still didn't work. No... that's
wrong. What really pissed me off was the way that LILO works. I sure
want to teach libsa about ext2fs and make it able to load Linux
kernels. That would also make upgrading our server to NetBSD much
easier. 

  So far I haven't seen a partition editor that really worked well
yet. FreeBSD has come closest.

]              Have encryption. Will travel.                    |1 Fish/2 Fish[
]   Michael Richardson, Sandelman Software Works, Ottawa, ON    |Red F./Blow F[
] mcr@sandelman.ottawa.on.ca http://www.sandelman.ottawa.on.ca/ |strong crypto[
] panic("Just another NetBSD/notebook using, kernel hacking, security guy");  [