From owner-freebsd-stable Thu Dec 14 19:46: 5 2000 From owner-freebsd-stable@FreeBSD.ORG Thu Dec 14 19:46:03 2000 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mail.clones.com (unknown [216.70.178.182]) by hub.freebsd.org (Postfix) with ESMTP id E6FAC37B400 for ; Thu, 14 Dec 2000 19:46:02 -0800 (PST) Received: from localhost (gross@localhost) by mail.clones.com (8.9.3/8.9.3) with ESMTP id TAA08758; Thu, 14 Dec 2000 19:46:47 -0800 Date: Thu, 14 Dec 2000 19:46:47 -0800 (PST) From: Glendon Gross To: Warner Losh Cc: Greg Lehey , Sam Zamarripa , stable@FreeBSD.ORG Subject: Re: Dedicated disks (was: Dangerously Dedicated) In-Reply-To: <200011200036.RAA16154@harmony.village.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Please correct me if I am wrong, but this discussion seems to revolve around a problem that results from nonstandard BIOS routines. On Sun, 19 Nov 2000, Warner Losh wrote: > In message <20001120105211.O58333@echunga.lemis.com> Greg Lehey writes: > : > No it isn't bogus. You can't boot off a DD disk on some machines > : > because the MBR is too bogus for the BIOS to cope with. > : > : So you put a Microsoft partition table on the boot disk. That doesn't > : mean you need it on the other disks. > > On some systems, this works. On others it doesn't. Some systems > throw a rod when they see the bogus partition table, even if it isn't > on the primary disk. > > : > The problem with DD is that we put a bogus MBR onto the disk. All > : > that is necessary to fix it would be to put a non-bgous MBR onto the > : > disk. > : > : Right, for those cases where it's needed. More specifically, we need > : to now how non-bogus it needs to be. > > It must describe most/all of the disk. It must allow the BIOS to > figure out the geometry so that the boot loader could read the disk > (note, I say could because it might not be the primary disk, and a > bogus partition could cause the BIOS to lose its brain). > > I think, and I haven't checked this out yet, that we could make the > partition end c/h/s rounded to the end of the cylinder nearest the > real end of the disk. > > Warner > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-stable" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message