From owner-freebsd-questions Sun Mar 24 14:03:00 1996 Return-Path: owner-questions Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id OAA27074 for questions-outgoing; Sun, 24 Mar 1996 14:03:00 -0800 (PST) Received: from genesis.atrad.adelaide.edu.au (genesis.atrad.adelaide.edu.au [129.127.96.120]) by freefall.freebsd.org (8.7.3/8.7.3) with ESMTP id OAA27069 for ; Sun, 24 Mar 1996 14:02:56 -0800 (PST) Received: from msmith@localhost by genesis.atrad.adelaide.edu.au (8.6.12/8.6.9) id IAA25534; Mon, 25 Mar 1996 08:47:32 +1030 From: Michael Smith Message-Id: <199603242217.IAA25534@genesis.atrad.adelaide.edu.au> Subject: Re: Booting off SCSI disks when two IDE disks also installed. (fwd) To: shap@AURORA.CIS.UPENN.EDU (Jonathan S. Shapiro) Date: Mon, 25 Mar 1996 08:47:31 +1030 (CST) Cc: dherbst@gradient.cis.upenn.edu, msmith@atrad.adelaide.edu.au, wes@intele.net, questions@freebsd.org In-Reply-To: <199603241715.MAA16402@eros.cis.upenn.edu> from "Jonathan S. Shapiro" at Mar 24, 96 12:15:57 pm MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-questions@freebsd.org X-Loop: FreeBSD.org Precedence: bulk A couple of points ... > Before you installed the second drive, the adaptec controller was > looking, saying "okay, scsi0 should become BIOS drive 0x81" and > installing the drive in the BIOS table and the adaptec ROM disk > BIOS as the BIOS for that drive. ... except that the SCSI disk was the newcomer on the scene. > Actually, my guess is that it wasn't installing the BIOS with one > drive either, and you were getting away with this by sheer luck and > register level compatibility. ... and Adaptec SCSI controllers aren't "register level compatible" with IDE controllers. Or anything else for that matter. The only SCSI controllers I know of that were "register level compatible" were the old Longshine LC400(?) cards that concatenated every SCSI disk you connected to them into a huge RAID -1 IDE disk. > If your board supports multiple IDE interfaces (many now support > two), you might find that you are able to make things work by > installing your 2nd drive on the 2nd interface. Even so, be aware > that you're playing with fire here, and not all boards will work. Most BIOSes will consider that to be the second drive. > I don't think that any of the fancy boot loaders will work for you. > Most of them are dependent on the BIOS. Almost all are inherently dependant on the BIOS. Some BIOSes support booting from higher disks than 0x81, Bruce's noew bootstrap code may help with this - I haven't cut it onto a disk to try out yet. > Jonathan > -- ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[ ]] Genesis Software genesis@atrad.adelaide.edu.au [[ ]] High-speed data acquisition and (GSM mobile) 0411-222-496 [[ ]] realtime instrument control (ph/fax) +61-8-267-3039 [[ ]] Collector of old Unix hardware. "Where are your PEZ?" The Tick [[