iSCSI: Flushing issues when multipath config has changed

[Gorka Eguileor]

OS-Brick disconnect_volume code assumes that the use_multipath parameter that is used to instantiate the connector has the same value than the connector that was used on the original connect_volume call.

Unfortunately this is not necessarily true, because Nova can attach a volume, then its multipath configuration can be enabled or disabled, and then a detach can be issued.

This leads to a series of serious issues such as:

- Not flushing the single path on disconnect_volume (possible data loss) and leaving it as a leftover device on the host when Nova calls terminate-connection on Cinder.
- Not flushing the multipath device (possible data loss) and leaving it as a lefover device similarly to the other case.

[Gorka Eguileor (gorka)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/os-brick/+/782992

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/os-brick 4.3.1 release.

[Balazs Gibizer (balazs-gibizer)]

Nova master (Xena) merged the os-brick min version bump in https://review.opendev.org/c/openstack/nova/+/783674
The stable/wallaby os-brick min version bump is in progress in https://review.opendev.org/c/openstack/nova/+/783822

[Balazs Gibizer (balazs-gibizer)]

The nova stable/wallaby patch has been merged https://review.opendev.org/c/openstack/nova/+/783822 and an RC2 including this fix has been proposed https://review.opendev.org/c/openstack/releases/+/784201

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/os-brick 4.0.3 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/os-brick 3.0.6 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/os-brick 2.10.6 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/os-brick 4.4.0 release.

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Brian Rosmaita <email address hidden>" on branch: stable/stein
Review: https://review.opendev.org/c/openstack/os-brick/+/785383
Reason: Stein transitioned to End of Life by change Icf9a539a7b8b and is accepting no more changes.