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From: Martin Simmons <martin@lispworks.com>
To: Borja Marcos <borjam@sarenet.es>
CC: jbe-mlist@magnetkern.de, freebsd-fs@freebsd.org
In-reply-to: <462E2C53-2490-4B8C-BB54-BCE8B75BAEB0@sarenet.es> (message from
 Borja Marcos on Thu, 21 Nov 2019 14:46:04 +0100)
Subject: Re: ZFS snapdir readability (Crosspost)
References: <20191107004635.c6d2e7d464d3d556a0d87465@magnetkern.de>
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>>>>> On Thu, 21 Nov 2019 14:46:04 +0100, Borja Marcos said:
> 
> > On 21 Nov 2019, at 13:59, Martin Simmons <martin@lispworks.com> wrote:
> > 
> >>>>>> On Thu, 21 Nov 2019 13:12:04 +0100, Borja Marcos said:
> >> 
> >> What I mean is, there is no snapshot mount functionality. If you want to access the
> >> contents of a snapshot you either rollback it or you clone it. There is no
> >> mount.
> > 
> > I think that is incorrect.  You can mount a snapshot on /mnt like this:
> > 
> > /sbin/mount -t zfs filesystem@snapname /mnt
> 
> I’ve never seen that and, indeed, on FreeBSD 12.1 it’s not possible. Or I am terribly
> sloppy today!
> 
> Did I miss anything? Is it a new ZFS on Linux feature?
> 
> 
> root@micro1:~ # mount -t zfs -o ro pool/dataset@snapshot /mnt
> mount: unpul/wwwnfsen@antesinst: Device busy
> root@micro1:~ # 

It looks like unpul/wwwnfsen@antesinst is already mounted -- probably in .zfs :-)

__Martin