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Date: Tue, 12 Aug 2014 17:14:56 -0300 (ADT)
From: Andrew Hamilton-Wright <AHamiltonWright@MtA.ca>
To: Roland Smith <rsmith@xs4all.nl>
Subject: Re: Problems with dump and restore
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Sorry, a bit of a follow up after some reading, as the soft-update
bit was itching in my memory...


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.

I have just realize that the soft update journal (newfs option -j enable)
is actually not in play here, however "soft updates" (option -U) is.  My
understanding of the referenced bug:
 	https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=160662
is that it is specifically referred to _journaled_ soft updates as being
a danger, but soft updates using -U are not referred to by this bug.

Is that your understanding as well?

I believe that when I set up the filesystems for this machine in the first
place, I specifically ensured that "-j disable" was chosen, for exactly
this reason -- however my logbook does not contain enough detail for
me to be sure.


To be clear then, do I understand that your filesystem options include
neither "-j enable" nor "-U"?

Thanks,
Andrew.