From owner-freebsd-hackers Mon Mar 17 10:55:00 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id KAA27109 for hackers-outgoing; Mon, 17 Mar 1997 10:55:00 -0800 (PST) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.50]) by freefall.freebsd.org (8.8.5/8.8.5) with SMTP id KAA27103 for ; Mon, 17 Mar 1997 10:54:57 -0800 (PST) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id LAA08211; Mon, 17 Mar 1997 11:43:45 -0700 From: Terry Lambert Message-Id: <199703171843.LAA08211@phaeton.artisoft.com> Subject: Re: wd and funky geometry (understood?) To: bde@zeta.org.au (Bruce Evans) Date: Mon, 17 Mar 1997 11:43:45 -0700 (MST) Cc: dgy@rtd.com, freebsd-hackers@freefall.freebsd.org, bde@zeta.org.au, joerg_wunsch@uriah.heep.sax.de In-Reply-To: <199703171346.AAA13488@godzilla.zeta.org.au> from "Bruce Evans" at Mar 18, 97 00:46:39 am X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk > >However, *both* drives have a BIOS geometry of 611/16/63. (Sorry, > >my ancient BIOS does not support "user configurable" geometries > >so this was the closest geometry I could find -- hence the reason > > What's the problem? The BIOS uses the fudged geometry that you told it, > but the FreeBSD driver knows better - there is no reason for it to use > a fudged geometry. The disk is shared with DOS and uses the DOS MBR. THe DOS MBR will use the fudged geometry, and the BSD DOS partition table entry must be in the fudged geometry to make the DOS MBR happy to boot it. > Of course you must use a consistently fudged geometry for everything > related to the BIOS. Like multiplying the C/H/S value by the fudged geometry in protected mode to find the BSD boot and disktab data. Regards, Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.