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Date: Sun, 19 May 2013 21:30:46 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v4 0/8] block: drive-backup live backup
	command
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To: "Richard W.M. Jones" <rjones@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>, qemu-devel@nongnu.org, dietmar@proxmox.com, imain@redhat.com, Stefan Hajnoczi <stefanha@redhat.com>, xiawenc@linux.vnet.ibm.com

Il 19/05/2013 18:47, Richard W.M. Jones ha scritto:
>> > 
>> > More advanced users may wish to make the target an NBD URL.  The NBD server
>> > listening on the other side can process the backup writes any way it wishes.  I
>> > previously posted an RFC series with a backup server that streamed Dietmar's
>> > VMA backup archive format.
> I'm guessing the answer is no, but thought I would ask:  Is there
> any way to use this to do point-in-time inspection of guests?

Almost, and even for an atomic copy of multiple disks.  All that is left
is to create the copy with the disk as a backing file, and switch the
backing file at the end of the copy.  It is a very simple change on top
of these patches.

Paolo

> AFAICT the only way to do it would be to make a complete copy of a
> guest disk in another file.