From owner-freebsd-scsi  Sat Jun  8 13:41:56 1996
Return-Path: owner-freebsd-scsi
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.5/8.7.3) id NAA15772
          for freebsd-scsi-outgoing; Sat, 8 Jun 1996 13:41:56 -0700 (PDT)
Received: from MindBender.HeadCandy.com (root@[199.238.225.168])
          by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id NAA15751;
          Sat, 8 Jun 1996 13:41:50 -0700 (PDT)
Received: from localhost.HeadCandy.com (michaelv@localhost.HeadCandy.com [127.0.0.1]) by MindBender.HeadCandy.com (8.7.5/8.6.9) with SMTP id NAA19365; Sat, 8 Jun 1996 13:37:35 -0700 (PDT)
Message-Id: <199606082037.NAA19365@MindBender.HeadCandy.com>
X-Authentication-Warning: MindBender.HeadCandy.com: Host michaelv@localhost.HeadCandy.com [127.0.0.1] didn't use HELO protocol
To: Dave Hayes <dave@kachina.jetcafe.org>
cc: freebsd-hackers@freebsd.org, freebsd-scsi@freebsd.org
Subject: Re: Using two NCR 53C825 controllers blows up? 
In-reply-to: Your message of Sat, 08 Jun 96 04:15:24 -0700.
             <199606081115.EAA08772@kachina.jetcafe.org> 
Date: Sat, 08 Jun 1996 13:37:18 -0700
From: "Michael L. VanLoon -- HeadCandy.com" <michaelv@HeadCandy.com>
Sender: owner-freebsd-scsi@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk


>In a Pent-133 I am trying to install with two of these NCR
>controllers in it, there are two disks per controller.
>
>When I boot off the floppy, the disks are numbered one way
>(sd0 thru sd3). Install proceeds happily. 
>
>Wben I boot off the installed operating system, the controller
>cards suddenly switch roles, causing sd0 to become sd2, and 
>causing a panic("cannot mount root");.

What kind of machine is this?

I know that Dell, for example, really screwed this up.  You could get
similar bad behavior under Windows NT (add a new disk on the external
controller, which DOS recognizes as D:; reboot into Windows NT and all
of a sudden the new disk is C:, and your old C: drive is now D:).

The problem there was that the second controller piggy-backed onto the
first, and the Dell BIOS artificially made the second controller
drives probe after the first controller's.

However, the "second" card was actually installed with a lower address
or IRQ or something.  The only thing that made it come "after" the
first was because it was hacked into the BIOS that way.  After
bootstrapping, NT doesn't use the BIOS anymore, and so would make the
"second" controller into the first controller under NT, and the
"first" controller would become the second.  The drives on the
controllers, of course, would then follow the new order.  Very very
annoying.

You might be seeing something similar.

-----------------------------------------------------------------------------
  Michael L. VanLoon                                 michaelv@HeadCandy.com
        --<  Free your mind and your machine -- NetBSD free un*x  >--
    NetBSD working ports: 386+PC, Mac 68k, Amiga, Atari 68k, HP300, Sun3,
        Sun4/4c/4m, DEC MIPS, DEC Alpha, PC532, VAX, MVME68k, arm32...
    NetBSD ports in progress: PICA, others...

   Roll your own Internet access -- Seattle People's Internet cooperative.
                  If you're in the Seattle area, ask me how.
-----------------------------------------------------------------------------