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Date: Tue, 12 Aug 2014 15:04:51 -0600 (MDT)
From: Warren Block <wblock@wonkity.com>
To: Roland Smith <rsmith@xs4all.nl>
Subject: Re: Problems with dump and restore
In-Reply-To: <20140812193419.GB7166@slackbox.erewhon.home>
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 (wonkity.com [127.0.0.1]); Tue, 12 Aug 2014 15:04:51 -0600 (MDT)
Cc: freebsd-questions@freebsd.org,
 Andrew Hamilton-Wright <AHamiltonWright@MtA.ca>
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On Tue, 12 Aug 2014, Roland Smith wrote:

> In 2011, a problem was found with snapshots in combination with soft
> updates *and* journaling (SU+J) hanging the machine. At that time the
> recommendation was to switch off journaling.
> According to https://wiki.freebsd.org/NewFAQs:
>
>    If you want to use snapshot (dump -L) then disable the soft updates
>    journal for that filesystem.
>
> This bug was fixed toward the end of 2011;
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=160662

The snapshot code still does not support snapshots of mounted SUJ 
filesystems: 
http://svnweb.freebsd.org/base/head/sys/ufs/ffs/ffs_snapshot.c?revision=262678&view=markup#l234