From: Ulli Horlacher <framstag@rus.uni-stuttgart.de>
To: linux-btrfs@vger.kernel.org
Subject: Re: how do I know a subvolume is a snapshot?
Date: Wed, 17 Jul 2019 11:11:00 +0200 [thread overview]
Message-ID: <20190717091100.GC3462@tik.uni-stuttgart.de> (raw)
In-Reply-To: <eff513b1-a77c-cd5f-5af7-87eae73cff6a@suse.com>
On Wed 2019-07-17 (11:24), Nikolay Borisov wrote:
>
>
> On 17.07.19 3. 2:24 G., Ulli Horlacher wrote:
>
> > I thought, I can recognize a snapshot when it has a Parent UUID, but this
> > is not true for snapshots of toplevel subvolumes:
>
> As you have asked this before - in my testing this is not true.
It is true on all my SUSE and Ubuntu systems, for all versions.
> Alternatively you have to parse the root tree - the ROOT_ITEM's offset
> member should be 0 for well-known trees/ordinary subvolume or the
> transaction id when the snapshot was created.
Where can I find this ROOT_ITEM offset member? Which command?
--
Ullrich Horlacher Server und Virtualisierung
Rechenzentrum TIK
Universitaet Stuttgart E-Mail: horlacher@tik.uni-stuttgart.de
Allmandring 30a Tel: ++49-711-68565868
70569 Stuttgart (Germany) WWW: http://www.tik.uni-stuttgart.de/
REF:<eff513b1-a77c-cd5f-5af7-87eae73cff6a@suse.com>
next prev parent reply other threads:[~2019-07-17 9:11 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-16 23:24 how do I know a subvolume is a snapshot? Ulli Horlacher
2019-07-17 7:45 ` Bernhard Kühnel
2019-07-17 8:05 ` Ulli Horlacher
2019-07-17 10:33 ` Remi Gauvin
2019-07-17 8:23 ` Hans van Kranenburg
2019-07-17 8:57 ` misono.tomohiro
2019-07-17 9:06 ` Ulli Horlacher
2019-07-17 9:24 ` misono.tomohiro
2019-07-17 8:24 ` Nikolay Borisov
2019-07-17 9:11 ` Ulli Horlacher [this message]
2019-07-17 10:11 ` Nikolay Borisov
2019-07-17 10:29 ` Andrei Borzenkov
2019-07-17 11:19 ` Nikolay Borisov
2019-07-17 17:39 ` Andrei Borzenkov
2019-07-17 18:16 ` Nikolay Borisov
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