Date: Wed, 13 Dec 1995 09:48:49 -0700
From: Tony Jones <tony@rtd.com>
Message-Id: <199512131648.JAA25533@seagull.rtd.com>
To: hackers@freebsd.org
Subject: Wiring down scsi id's
Sender: owner-hackers@freebsd.org
Precedence: bulk

I asked this on -questions and didn't get any replies.
Can anyone give me some suggestions ?

Running 2.0.5 on a ASUS P/I-P55TP4XE with NCR SCSI.

thanks!

-------------------------------------------------------------

I'm obviously missing something fairly major here, can anyone 
enlighten me.

Have 3 scsi discs
	id0	quantum (Win95)
	id1	dec (FreeBSD root/usr/var)
	id2	dec (FreeBSD src/home)

Booteasy installed on id0 and id1.

Occasionally I'll remove the quantum, which causes the dynamic sdN allocation.
to change (dec drives become sd0 and sd1) which causes fsck(fstab) problems.

So, I decided I'd fix down the scsi id's

	config kernel root on sd0

	disk sd0 at scbus0 target 1
	disc sd1 at scbus0 target 2

I _thought_ this would do the trick. 

Works OK if the Quantum is removed/powered off.

If I add the Quantum back in ...  System boots with the Quantum in place, 
assigns id0 to sd2, id1 to sd0 and id2 to sd1.

Then it sets root device to *sd1* and barfs trying to mount root as sd1a. Seems 
to be getting sd1 from the fact that I'm booting off id1.

So, I switched tack a little

	config kernel root on sd1
	disk sd1 at scbus0 target 1
	disc sd2 at scbus0 target 2

System boots with the Quantum in place, assigns id0 to sd3, id1 to sd1
and id2 to sd2.

Works.

If I remove the Quantum,  system boots, assigns id1 to sd1, id2 to sd2,
get the same problem, tries to mount root  off *sd0*.

I'm getting the feeling that the root disc assignment is being affected
by the bios' C: D: scsi assignment, and that my 'config kernel root on XXX' 
line is being ignored.

Anyone have any ideas on what I am missing ?

tony