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Date: Mon, 28 Apr 2014 21:29:37 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Rick Macklem <rmacklem@uoguelph.ca>
Subject: Re: RFC: using ceph as a backend for an NFSv4.1 pNFS server
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Cc: freebsd-fs@freebsd.org, Ivan Voras <ivoras@freebsd.org>
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On Mon, Apr 28, 2014 at 08:37:19PM -0400, Rick Macklem wrote:
>   2 - Block/volume, where the client uses iSCSI to read/write blocks for
>       the file's data.

There is nothing iSCSI specific in the block layout spec, even if that
seems to be the reference implementation.  Any block device that allows
multiple initiators will do.