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Date: Thu, 22 Oct 2015 18:06:42 +0800
From: Fam Zheng <famz@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 0/2] Fix werror=enospc for qcow2 on iscsi
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To: Peter Lieven <pl@kamp.de>
Cc: Kevin Wolf <kwolf@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, qemu-block@nongnu.org, qemu-devel@nongnu.org, Ronnie Sahlberg <ronniesahlberg@gmail.com>

On Thu, 10/22 10:32, Peter Lieven wrote:
> Am 22.10.2015 um 10:17 schrieb Fam Zheng:
> >When qcow2 is created on iscsi target with a virtual size greater than physical
> >capacity of the LUN, over time it's possible that guest fills too much data and
> >at that point, new clusters in qcow2 will be allocated beyond the end of disk.
> 
> Why would you want to put a QCOW2 on a fixed size block device?
> 

It can have a backing file.

Fam