On Wed, Jul 11, 2012 at 7:37 AM, Eric Blake
<eblake@redhat.com> wrote:
Unfortunately, block migration during migration is an all-or-none
prospect. And qemu 1.1 does not provide enough tools to do anything
differently, short of creating a snapshot file where the snapshot delta
is on shared storage, and then you manually copy the backing file into
place on the destination, then migrate without copying storage; but
there is no way to coalesce things back into one file once you take the
snapshot.
Qemu 1.2 will be adding some new features that allow for block storage
migration as well as live commits (coalescing a delta snapshot file back
into its backing file) which can then be exposed through libvirt to
provide more functionality into what you want to do.
> Does the concept of storage pool help this? I browse the source
> code but don't find hints right now.
A storage pool lets you inform libvirt where your shared storage lives,
but does not help with the aspect of whether live storage migration is
possible in the underlying qemu.
--
Eric Blake eblake@redhat.com +1-919-301-3266
Libvirt virtualization library http://libvirt.org