3PAR driver doesn't remove all VLUNs after a volume detach in some situations

[Anthony Lee]

The 3PAR FC and iSCSI drivers will sometimes not remove all VLUNs from the backend after a volume detach has occured.

One situation where this can happen is if multiple VLUNs are connected to a volume. Currently the 3PAR driver will only call the backend with a request to remove the first VLUN associated with the volume. The other VLUNs will usually be removed, but sometimes not all will be deleted. A change needs to be made to make sure an attempt to remove all VLUNs is done in order to ensure none are left over.

Another situation where VLUNs end up being left over after a volume detach is during live migration. Nova calls initialize_connection several times during live migration. Currently the 3PAR FC and iSCSI drivers will create a new VLUN each time initialize_connection is called. This results in possible dangling VLUNs once the live migration process has completed. A change is needed to only return connection info if a VLUN is already attached to a volume (as this is what Nova currently assumes initialize_connection will do).

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/196164
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=b068ae93e26d21cb94504ac2f70231361acd38e6
Submitter: Jenkins
Branch: master

commit b068ae93e26d21cb94504ac2f70231361acd38e6
Author: Anthony Lee <email address hidden>
Date: Fri Jun 26 10:38:33 2015 -0700

    Improve 3PAR driver VLUN creation and deletion

    This patch improves the creation and deletion logic for VLUNs
    for the 3PAR drivers. The changes will help to prevent VLUNs
    from being left behind after volume detaches. It also prevents
    extra VLUNs being created when initialize_connection is called
    multiple times for the same volume and host.

    Closes-Bug: #1469816
    Change-Id: I497564cb4bd661252570eb2e69962f7d5f3c07da

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/kilo
Review: https://review.openstack.org/226971

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/kilo
Review: https://review.openstack.org/227050

[OpenStack Infra (hudson-openstack)]

Change abandoned by Anthony Lee (<email address hidden>) on branch: stable/kilo
Review: https://review.openstack.org/226971
Reason: creating a new patch that is correctly cherry picked.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/227050
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=64998f1c8c12a2c8575b0b7027e010955c2203eb
Submitter: Jenkins
Branch: stable/kilo

commit 64998f1c8c12a2c8575b0b7027e010955c2203eb
Author: Anthony Lee <email address hidden>
Date: Wed Sep 23 12:59:53 2015 -0700

    Improve 3PAR driver VLUN creation and deletion

    This patch improves the creation and deletion logic for VLUNs
    for the 3PAR drivers. The changes will help to prevent VLUNs
    from being left behind after volume detaches. It also prevents
    extra VLUNs being created when initialize_connection is called
    multiple times for the same volume and host.

    Closes-Bug: #1469816
    Change-Id: I497564cb4bd661252570eb2e69962f7d5f3c07da
    (cherry picked from commit b068ae93e26d21cb94504ac2f70231361acd38e6)