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From: Orit Wasserman <owasserm@redhat.com>
Date: Wed, 14 Sep 2011 19:36:49 +0300
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Subject: Re: [Qemu-devel] [PATCH] Add iSCSI support for QEMU
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, stefanha@linux.vnet.ibm.com, qemu-devel@nongnu.org, fujita.tomonori@lab.ntt.co.jp, RonnieSahlberg <ronniesahlberg@gmail.com>, Christoph Hellwig <hch@lst.de>

On Wed, 2011-09-14 at 16:51 +0100, Stefan Hajnoczi wrote:
> On Wed, Sep 14, 2011 at 4:40 PM, Christoph Hellwig <hch@lst.de> wrote:
> > On Wed, Sep 14, 2011 at 04:35:50PM +0100, Stefan Hajnoczi wrote:
> >> I think the motivation for iSCSI target support in QEMU is exactly
> >> what you mentioned - providing shared storage.  In migration scenarios
> >> it is necessary temporarily make shared storage possible with an image
> >> that is on a local disk.
> >
> > Why do we need to use the complex iSCSI protocol for that instead of
> > simply using NBD?
> 
> I think NBD would be fine, especially with a flush command.
If I remember correctly , there is a problem with NBD with an image with
a backing file chain . NBD client only displays a single file image.
With ISCSI we can use different luns per image file.
Orit
> 
> Stefan