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Subject: Re: ZFS should prefer the most specific... or something.
To: freebsd-hackers@freebsd.org,Zaphod Beeblebrox <zbeeble@gmail.com>
From: Allan Jude <allanjude@FreeBSD.org>
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On February 26, 2017 3:31:54 PM PST, Zaphod Beeblebrox <zbeeble@gmail=2Ecom=
> wrote:
>So, my experience is that I added two drives (that showed up as ada0
>and
>ada1) =2E=2E=2E something odd with the raid card added a da0 =2E=2E=2E wh=
ich is
>unreadable =2E=2E=2E seems to be a bogon=2E
>
>=2E=2E=2E and ZFS, in it's infinite wisdom changes my nice, neat da0s2a z=
fs
>to
>diskid/<blahblahblah>s2a=2E
>
>=2E=2E=2E this is doubly bad, because then the /dev/da0s1a cannot mount a=
s
>swap=2E
>
>I realize that this is can be somewhat fixed for non-root zfs with
>import/export, but for root ZFS =2E=2E=2E you're stuck=2E
>
>Can we have ZFS prefer the shortest (rather than longest)?  Can we have
>it
>prefer labels, if they exist (have a priority field in the different
>types
>of geom =2E=2E=2E an order in which they are tasted)?
>
>The current situation has been annoying multiple distinct times=2E
>_______________________________________________
>freebsd-hackers@freebsd=2Eorg mailing list
>https://lists=2Efreebsd=2Eorg/mailman/listinfo/freebsd-hackers
>To unsubscribe, send any mail to
>"freebsd-hackers-unsubscribe@freebsd=2Eorg"

Zfs has no Control over this, it is GEOM that decides the device names=2E =
There are multiple for each disk, and once one is used, geom hides the rest=
=2E As Alan Somers pointed out, you can disable the names you do not want=
=2E

Disk ID can be useful as it is the serial number of the disk
--=20
Allan Jude