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From: Wolfgang Helbig <helbig@MX.BA-Stuttgart.De>
Message-Id: <199706270756.JAA27070@helbig.informatik.ba-stuttgart.de>
Subject: Re: Root on secondary master IDE drive
In-Reply-To: <199706270058.UAA20895@townhouse.dyn.ml.org> from Matthew Hunt at "Jun 26, 97 08:58:16 pm"
To: mph@pobox.com (Matthew Hunt)
Date: Fri, 27 Jun 1997 09:56:58 +0200 (MET DST)
Cc: freebsd-questions@FreeBSD.ORG
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> I helped to setup FreeBSD 2.2.2 on a friend's computer today.  It has
> Windows on wd0, no wd1, and FreeBSD on wd2.
> 
> We can boot FreeBSD from the boot prompt using:
> 
> 1:wd(2,a)/kernel
> 
> Then everything's fine.  In order to make the root device wd2a
> permanently, I did the obvious:
> 
> config kernel root on wd2

This does not seem to define the disk the kernel is looking for the
root system. Its defined by the bootstring only.

> I have confirmed that config parsed it correctly, because in the
> compile directory we have a swapkernel.c with:
> 
> dev_t   rootdev = makedev(0, 0x00000010);               /* wd2a */
> 
> However, on booting the new kernel (yes, it is the new kernel) tries
> to mount wd1a, which doesn't exist.  Obviously, it panics.
> 
> Anybody have any ideas?

Use nextboot(8) to make your bootstring permanent.
Or switch the names "wd0" and "wd2" in your kernel config file, so
"wd0" points to the master drive of the second IDE controller, and
"wd2" points to the master drive of the first IDE controller.

Don't forget to update the file system table /etc/fstab before rebooting
the new kernel.

Wolfgang