---
features:
  - |
    This change ensures the synchronization of volume attachments
    between Nova and Cinder, by deleting any dangling volume attachments
    and maintaining consistency between two databases.

    Block device mapping (BDM) table in the Nova database, stores
    information about volume attachments, image attachments
    and swap attachments. Similarly, each volume attachment had a
    corresponding entry in the Cinder database volume attachment table.

    With this change, on instance reboot, Nova will checks for all volume
    attachments associated with the instance and verifies their availability
    in the Cinder database. If attachments are not found they will get deleted
    from Nova database too.

    After Nova database cleanup, similarly Cinder database is checked for
    attachments related to instance. If attachments found in Cinder DB that
    are not present in Nova DB, they will get deleted from Cinder database.

    See `spec`__ for more details.

    __ https://specs.openstack.org/openstack/nova-specs/specs/2023.2/approved/cleanup-dangling-volume-attachments.html