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Date: Thu, 04 Jul 2013 10:25:39 +0800
From: David Xu <davidxu@freebsd.org>
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To: Berend de Boer <berend@pobox.com>
Subject: Re: EBS snapshot backups from a FreeBSD zfs file system: zpool freeze?
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On 2013/07/03 17:17, Berend de Boer wrote:
>>>>>> "David" == David Xu <davidxu@freebsd.org> writes:
>
>      David> What you need is a tool to create snapshot on EBS server,
>
> FYI, EBS is not a server. It is NAS. It's block storage.
>
> --
> All the best,
>
> Berend de Boer
>

You can call it as NAS, but in pratical it is implemented as a server
farm, we do have implemented a local EBS farm, normally, a command can
be sent to a master server to request a snapshot for its client, the
client can continuely writes to its iSCSI disk without being suspended 
by snapshot. HW snapshot is not a problem, because our clients uses
journal file system, the snapshot even in inconsistent state will be 
recovered by its client OS when it is mounted. So our client does not
need to support file system suspending or snapshot, only needs a journal
file system.

Regards,
David Xu