From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sylvain Bauza <sylvain.bauza@digimind.com>
Subject: Re: Win2003 disk corruption with kvm-1.0. and virtio
Date: Thu, 14 Feb 2013 11:11:33 +0100
Message-ID: <511CB855.9090803@digimind.com>
References: <511A520D.4@digimind.com> <20130213090317.GA12049@stefanha-thinkpad.redhat.com> <511B628A.3040005@digimind.com> <20130214081543.GA3809@stefanha-thinkpad.redhat.com>
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To: Stefan Hajnoczi <stefanha@gmail.com>
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Interesting point you mention. Even if qcow2 is read only, the image is=
=20
changing (especially, I'm running IIS with ASP support and VB DLLs)=20
while the snapshot is taken.

As asked in a second post, I'm running with latest Windows virtio=20
drivers, but I only apply a virtio driver update *after* running an=20
instance, not before taking the snapshot.

What I'll try : run an instance, update the driver, stop the instance,=20
do a qemu-img convert once the instance is stopped.


Le 14/02/2013 09:15, Stefan Hajnoczi a =E9crit :
> On Wed, Feb 13, 2013 at 10:53:14AM +0100, Sylvain Bauza wrote:
>> As per documentation, Nova (Openstack Compute layer) is doing a
>> 'qemu-img convert -s' against a running instance.
>> http://docs.openstack.org/trunk/openstack-compute/admin/content/crea=
ting-images-from-running-instances.html
> That command will not corrupt the running instance because it opens t=
he
> image read-only.
>
> It is possible that the new image is corrupted since qemu-img is read=
ing
> from a qcow2 file that is changing underneath it.  However, the chanc=
e
> is small as long as the snapshot isn't deleted while qemu-img convert=
 is
> running.
>
> So this doesn't sound like the cause of the problems you are seeing.
>
> Stefan