Cinder backup - The multipath flag is not set on a create_backup operation

[Helen Walsh]

Operation:
Cinder backup create_backup of an attached volume where multipathing is enabled

How to reproduce:
1. Make sure multipathing is enabled
2. Create an instance from a bootable volume (in-use)
3. Make a backup of that volume
    $ openstack volume backup create --force --name backup1 678a3b27-ef07-4be7-990a-0fcab0210058

4. Check the logs. The 'multipath' flag is False

DEBUG os_brick.utils [req-f9b88931-5ac5-4172-ad9b-edd0670eaac5 req-6c9c1abe-751b-48fe-8d9c-a96004d4f29b admin None] <== get_connector_properties: return (1180ms) {'platform': 'x86_64', 'os_type': 'linux', 'ip': '10.60.141.67', 'host': 'xxxxxxxx', 'multipath': False, 'initiator': 'iqn.2005-03.org.open-iscsi:xxxxxxxx', 'wwpns': ['10000000c95xxxxx', '10000000c95xxxxx'], 'wwnns': ['20000000c95xxxxx', '20000000c95xxxxx'], 'do_local_attach': False, 'uuid': '9a036057-6cdd-4120-94f1-507ae655889e', 'system uuid': '4226039f-fa43-d9a2-8c00-c3d1fabc6c56'} {{(pid=382363) trace_logging_wrapper /usr/local/lib/python3.8/dist-packages/os_brick/utils.py:184}}

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/cinder/+/818994

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/cinder/+/818994
Committed: https://opendev.org/openstack/cinder/commit/bf23678fe0f8583f80dc216ecbe645debb044220
Submitter: "Zuul (22348)"
Branch: master

commit bf23678fe0f8583f80dc216ecbe645debb044220
Author: Gorka Eguileor <email address hidden>
Date: Tue Nov 23 17:27:24 2021 +0100

    Honor multipath config everywhere

    There are multiple places in Cinder where the os-brick call to get the
    connector properties is not passing the "multipath" and
    "enforce_multipath" configuration options.

    This means that some driver won't return a multipathed connection
    information on the initialize_connection RPC call, resulting in a single
    pathed attachment even when the os-brick connector is instantiated with
    the right configuration option.

    This patch fixes the different calls where this is an issue:

    - Backup create
    - Backup restore
    - Kaminario create volume from snapshot
    - Kaminario create volume from volume
    - Volume rekeying

    And also in places where this is not affecting operations because
    drivers are always returning multipathed information:

    - Unity driver
    - IBM FlashSystem

    Closes-Bug: #1951982
    Closes-Bug: #1951977
    Closes-Bug: #1951981
    Change-Id: I73ab87b5aaa4835a814389bc1cdd8016d75f52ef

[Tarun Mathur (tkmathur)]

Can we please backport this fix to Yoga?

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 21.0.0.0rc1 release candidate.