Comment 1 for bug 1954883

Reviewed: https://review.opendev.org/c/openstack/glance_store/+/819481
Committed: https://opendev.org/openstack/glance_store/commit/3d221ec529862d43ab303644e74ee9ad6ce8cd40
Submitter: "Zuul (22348)"
Branch: master

commit 3d221ec529862d43ab303644e74ee9ad6ce8cd40
Author: Abhishek Kekane <email address hidden>
Date: Fri Nov 26 14:58:23 2021 +0000

    [RBD] Clone v2: Image is unusable if deletion fails

    Recently cinder has utilized Ceph clone v2 support for its
    RBD backend, since then if you attempt to delete an image from
    glance that has a dependent volume, all future uses of that
    image will fail in error state. Despite the fact that image
    itself is still inside of Ceph/Glance. This issue is reproducible
    if you are using ceph client version greater than 'luminous'

    To resolve this issue glance RBD driver now checks whether snapshot
    of original image has any external references before deleting/removing
    it's snapshot and returns 409 Conflict response if it has any.

    NOTE: To check this dependency glance osd needs 'read' access to
    cinder and nova side RBD pool.

    Closes-Bug: #1954883
    Depends-on: https://review.opendev.org/c/openstack/devstack-plugin-ceph/+/819476
    Change-Id: If30b7bd7acac148b6f89ce46abbe128c678c90e7