--- other: - | The ``resize`` and ``migrate`` server action APIs used to synchronously block until a destination host is selected by the scheduler. Those APIs now asynchronously return a response to the user before scheduling. The response code remains 202 and users can monitor the operation via the ``status`` and ``OS-EXT-STS:task_state`` fields on the server resource and also by using the ``os-instance-actions`` API. The most notable change is ``NoValidHost`` will not be returned in a 400 error response from the API if scheduling fails but that information is available via the instance actions API interface.