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Date: Thu, 07 Apr 2011 15:16:36 +0300
From: Daniel Kalchev <daniel@digsys.bg>
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To: Pete French <petefrench@ingresso.co.uk>
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Cc: freebsd-stable@freebsd.org
Subject: Re: ZFS HAST config preference
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On 06.04.11 15:55, Pete French wrote:
> Or, I could use ZFS volumes and run HAST on top of these. This means,
>> that on each blade, I will have an local ZFS pool. Let's call this setup2.
> ...you would need to put a filesystem on to of the
> HAST filesystem though, what would that be ?

Thanks for your comments Pete.

The idea here is to have local ZFS pool(s) on each of the nodes. Then, 
in each local ZFS pool create ZFS volumes and use these for HAST. On the 
HAST device, I would again run ZFS, just without any redundancy. Just to 
avoid having to run fsck after switching roles.

This should, I guess, permit safe use of cache and log devices for 
pools, thus increasing performance. However, no idea how reliability 
will be affected if sudden loss of one node happens, especially the 
active node.

It seems I am going with setup1 for now, going live in about a week.

Daniel