Unity: Failed to detach LUN when auto zone enabled

[Ryan Liang]

The exception raised when detaching LUN.
The auto zone is enabled.

The root cause is that the LUN is the last LUN attached to the host. After detaching it, the `host.host_luns` is None.
To fix this issue, add None check.

2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils Traceback (most recent call last):
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils File "/usr/lib/python2.7/site-packages/powervc_cinder/zonemanager/powervc_utils.py", line 570, in decorator
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils info = terminate_connection(self, *args, **kwargs)
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils File "/usr/lib/python2.7/site-packages/cinder/volume/drivers/dell_emc/unity/driver.py", line 166, in terminate_connection
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils return self.adapter.terminate_connection(volume, connector)
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils File "/usr/lib/python2.7/site-packages/cinder/utils.py", line 883, in trace_logging_wrapper
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils result = f(*args, **kwargs)
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils File "/usr/lib/python2.7/site-packages/cinder/volume/drivers/dell_emc/unity/adapter.py", line 317, in terminate_connection
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils return self._terminate_connection(lun, connector)
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils File "/usr/lib/python2.7/site-packages/cinder/utils.py", line 883, in trace_logging_wrapper
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils result = f(*args, **kwargs)
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils File "/usr/lib/python2.7/site-packages/cinder/volume/drivers/dell_emc/unity/adapter.py", line 746, in _terminate_connection
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils if len(host.host_luns) == 0:
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils TypeError: object of type 'NoneType' has no len()
2018-03-26 09:29:31.595 55283 ERROR powervc_cinder.zonemanager.powervc_utils

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/556803

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/556803
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=c816be897e7ab1c95b38979b2cc94ecf179e44e7
Submitter: Zuul
Branch: master

commit c816be897e7ab1c95b38979b2cc94ecf179e44e7
Author: Ryan Liang <email address hidden>
Date: Wed Mar 28 07:30:39 2018 +0000

    Unity: fail to detach lun when auto zone enabled

    When the lun is the last one attached to the host and it is detached,
    the attribute `host.host_luns` is None. Use `not` in if statement which
    is pythonic in checking None and empty list of `host.host_luns`.

    Change-Id: I5d8f63f9a78d001bc699af538f586aab8d73a5cf
    Closes-bug: #1759175

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/queens
Review: https://review.openstack.org/558659

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/pike
Review: https://review.openstack.org/558662

[OpenStack Infra (hudson-openstack)]

Change abandoned by Ryan Liang (<email address hidden>) on branch: stable/pike
Review: https://review.openstack.org/558662
Reason: According to Eric's comments, need to cherry pick from Queens.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/558659
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=febe57cfee50425c0fc9945169b5f9c3898cbdfe
Submitter: Zuul
Branch: stable/queens

commit febe57cfee50425c0fc9945169b5f9c3898cbdfe
Author: Ryan Liang <email address hidden>
Date: Wed Mar 28 07:30:39 2018 +0000

    Unity: fail to detach lun when auto zone enabled

    When the lun is the last one attached to the host and it is detached,
    the attribute `host.host_luns` is None. Use `not` in if statement which
    is pythonic in checking None and empty list of `host.host_luns`.

    Change-Id: I5d8f63f9a78d001bc699af538f586aab8d73a5cf
    Closes-bug: #1759175
    (cherry picked from commit c816be897e7ab1c95b38979b2cc94ecf179e44e7)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 13.0.0.0b1 development milestone.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/558662
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=ead818199e07923760e525c0367c9dcb5f4ab343
Submitter: Zuul
Branch: stable/pike

commit ead818199e07923760e525c0367c9dcb5f4ab343
Author: Ryan Liang <email address hidden>
Date: Wed Mar 28 07:30:39 2018 +0000

    Unity: fail to detach lun when auto zone enabled

    When the lun is the last one attached to the host and it is detached,
    the attribute `host.host_luns` is None. Use `not` in if statement which
    is pythonic in checking None and empty list of `host.host_luns`.

    Change-Id: I5d8f63f9a78d001bc699af538f586aab8d73a5cf
    Closes-bug: #1759175
    (cherry picked from commit c816be897e7ab1c95b38979b2cc94ecf179e44e7)
    (cherry picked from commit febe57cfee50425c0fc9945169b5f9c3898cbdfe)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 12.0.2 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/cinder 11.1.1 release.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/ocata
Review: https://review.openstack.org/625855

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/625855
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=e704e834024cf4ec156527b16f7437f9dba4d551
Submitter: Zuul
Branch: stable/ocata

commit e704e834024cf4ec156527b16f7437f9dba4d551
Author: Ryan Liang <email address hidden>
Date: Wed Mar 28 07:30:39 2018 +0000

    Unity: fail to detach lun when auto zone enabled

    When the lun is the last one attached to the host and it is detached,
    the attribute `host.host_luns` is None. Use `not` in if statement which
    is pythonic in checking None and empty list of `host.host_luns`.

    Change-Id: I5d8f63f9a78d001bc699af538f586aab8d73a5cf
    Closes-bug: #1759175
    (cherry picked from commit c816be897e7ab1c95b38979b2cc94ecf179e44e7)
    (cherry picked from commit febe57cfee50425c0fc9945169b5f9c3898cbdfe)
    (cherry picked from commit ead818199e07923760e525c0367c9dcb5f4ab343)