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Date: Mon, 29 Nov 2004 13:39:58 +0100
From: Andrea Campi <andrea+freebsd_stable@webcom.it>
To: Michael Grant <mg-fbsd3@grant.org>
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cc: freebsd-stable@freebsd.org
Subject: Re: bios disk numbers and device names
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On Mon, Nov 29, 2004 at 07:21:00AM -0500, Michael Grant wrote:
> Has anyone thought about this problem?  Is there some spare space in
> the label that could be used for a device name that, if set, could
> be used in place of (or an alias for) a name like da0?

GEOM_LABEL is what you're looking for. Check the glabel(8) man
page. In a nutshell, you'd do this:

tunefs -L log /dev/ad1s1a
tunefs -L db /dev/da4s1a
tunefs -L www /dev/da4s1a
...

mount /dev/ufs/log /mnt/log
mount /dev/ufs/db /mnt/db
mount /dev/ufs/www /mnt/www

(you get the idea). Obviously you can move use the /dev/ufs/*
devices in fstab as well.

If later on you move the filesystems to a different device while
retaining the label (which means no tar, you have to use dd or
dump/restore), everything works.

Hope it helps. Bye,
	Andrea

-- 
            Give a man a fish and you feed him for a day;
     teach him to use the Net and he won't bother you for weeks.