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Date: Tue, 2 Jan 1996 19:29:16 +0100
From: Juergen Lock <nox@jelal.hb.north.de>
Message-Id: <199601021829.TAA13667@saturn>
To: bde@zeta.org.au
Subject: Re: boot from sd1?
Cc: hackers@freebsd.org
In-Reply-To: <199512310553.QAA19389@godzilla.zeta.org.au>
Sender: owner-hackers@freebsd.org
Precedence: bulk

In article <199512310553.QAA19389@godzilla.zeta.org.au> you write:
>>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'.

Heyy...  maybe this is a silly idea :)  but what about adding the
root device to the list of things configurable with -c?  default (-1?)
is whatever the boot code (bios) guessed like its now, if thats wrong
(`cannot mount root') simply reboot with -c and tell the kernel where
it really is.  then write this back in dset -q...
>
>Bruce
	Juergen