Re: [Qemu-devel] [PATCH v4 0/8] block: drive-backup live backup command

[Paolo Bonzini]

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.