At present, we can modify the properties in the instance system_metadata through the sub command image_property of nova-manage, but there may be inconsistencies between their values and those in request_specs. And the migration is based on request_specs, so the same image properties are also written to request_specs. Closes-Bug: 2078999 Change-Id: Id36ecd022cb6f7f9a0fb131b0d202b79715870a9