---
upgrade:
  - |
    The ``image_ref_url`` entry in legacy instance notification payloads will
    be just the instance image id if ``[glance]/api_servers`` is not set
    and the notification is being sent from a periodic task. In this case the
    periodic task does not have a token to get the image service endpoint URL
    from the identity service so only the image id is in the payload. This
    does not affect versioned notifications.
