Comment 10 for bug 1978958

Reviewed: https://review.opendev.org/c/openstack/nova/+/872116
Committed: https://opendev.org/openstack/nova/commit/d00a848a735f98b028f5930798ee69ef205c8e2e
Submitter: "Zuul (22348)"
Branch: stable/zed

commit d00a848a735f98b028f5930798ee69ef205c8e2e
Author: Rajesh Tailor <email address hidden>
Date: Wed Aug 10 18:15:04 2022 +0530

    Fix rescue volume-based instance

    As of now, when attempting to rescue a volume-based instance
    using an image without the hw_rescue_device and/or hw_rescue_bus
    properties set, the rescue api call fails (as non-stable rescue
    for volume-based instances are not supported) leaving the instance
    in error state.

    This change checks for hw_rescue_device/hw_rescue_bus image
    properties before attempting to rescue and if the property
    is not set, then fail with proper error message, without changing
    instance state.

    Related-Bug: #1978958
    Closes-Bug: #1926601
    Change-Id: Id4c8c5f3b32985ac7d3d7c833b82e0876f7367c1
    (cherry picked from commit 6eed55bf55469f4ceaa7d4d4eb1be635e14bc73b)