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Date: Sun, 31 Dec 1995 16:53:23 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199512310553.QAA19389@godzilla.zeta.org.au>
To: bjj@sequent.com, dgy@rtd.com
Subject: Re: boot from sd1?
Cc: freebsd-hackers@freefall.freebsd.org
Sender: owner-hackers@FreeBSD.ORG
Precedence: bulk

>Question:  I have wd0, sd0, sd1, and I boot from sd0 (from before I had
>the wd0 drive).  When I was running 2.0.5, I patched the boot code to
>default to hd1 so that after getting the secondary boot block off of
>wd0, it would actually boot from sd0.  After I installed 2.1.0, I made
>the same change.  Now, however, after successfully booting from sd0,
>the kernel panics because it isn't pointing at sd0a as the root device.
>What did I miss?

It should work.  The hard part is getting the kernel started.  I've
often recovered from a wrong root device by booting with -d to run
ddb early (with a kernel compiled with options DDB of course) and
editing `bootdev'.

Bruce