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Date: Sat, 4 Feb 2017 22:57:23 +0100
From: Polytropon <freebsd@edvax.de>
To: Roger Marquis <marquis@roble.com>
Cc: freebsd-questions@freebsd.org
Subject: Re: Disappearing /dev/diskid/DISK*
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On Sat, 4 Feb 2017 11:42:07 -0800 (PST), Roger Marquis wrote:
> What would cause these entries be disappearing and reappearing, several
> days apart, on an 11.0-RELEASE-p6 system with ZFS root?

Other than the obvious (disks physically disconnecting),
I could imagine this has something to do with labels
(or in this case specifically, with disk serial numbers).
When a label is being used, for example to mount a
partition, the corresponding entry in the /dev subtree
will disappear, i. e. only those _not_ in use are present
there. Could it be some "automount"-related thing (when
you say it's happening more or less randomly)?

Maybe related:

https://www.freebsd.org/doc/handbook/geom-glabel.html

https://lists.freebsd.org/pipermail/freebsd-geom/2014-June/005921.html

http://bradleythughes.github.io/2015/05/06/booting-freebsd-zfs-raw-disks.html

https://forums.freebsd.org/threads/47671/


-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...