gluster_native: 'manila snapshot delete' fails with gluster 3.7.x as backend

[karthick]

Description:

With gluster version 3.7.x, The name of snapshot taken on gluster volume has time stamp appended to it. The glusterfs_native driver looks for snapshots with just the name and this mismatch prevents 'manila snapshot delete'.

$ manila snapshot-delete e3d11667-bc2d-4916-831f-d4ee1a3b1566

Appending timestamp to the name of snapshot was introduced as a fix to this bug
https://bugzilla.redhat.com/show_bug.cgi?id=1189473

Snippet of /var/log/manila/share.log

2015-07-09 11:34:13.239 23840 WARNING manila.context [-] Arguments dropped when creating context: {u'user': u'4b6679e3794e4357ac7a8224a6f60cf0', u'tenant': u'3c43a2a3a16b4426afa541cae48cbb27'}
2015-07-09 11:34:13.336 23840 ERROR oslo_messaging.rpc.dispatcher [req-db1bf931-37f9-4183-b337-97839b6f0f7a ] Exception during message handling: Deleting snapshot e3d11667-bc2d-4916-831f-d4ee1a3b1566 of share 71e0949f-6815-4844-b513-2ee2aa1d0292 failed with 30807: Snapshot (e3d11667-bc2d-4916-831f-d4ee1a3b1566) does not exist
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher Traceback (most recent call last):
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/dispatcher.py", line 142, in _dispatch_and_reply
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher executor_callback))
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/dispatcher.py", line 186, in _dispatch
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher executor_callback)
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/dispatcher.py", line 130, in _do_dispatch
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher result = func(ctxt, **new_args)
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/manila/share/manager.py", line 578, in delete_snapshot
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher {'status': 'error_deleting'})
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 85, in __exit__
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher six.reraise(self.type_, self.value, self.tb)
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/manila/share/manager.py", line 571, in delete_snapshot
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher share_server=share_server)
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher File "/usr/lib/python2.7/site-packages/manila/share/drivers/glusterfs_native.py", line 703, in delete_snapshot
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher 'errstr': operrstr})
2015-07-09 11:34:13.336 23840 TRACE oslo_messaging.rpc.dispatcher GlusterfsException: Deleting snapshot e3d11667-bc2d-4916-831f-d4ee1a3b1566 of share 71e0949f-6815-4844-b513-2ee2aa1d0292 failed with 30807: Snapshot (e3d11667-bc2d-4916-831f-d4ee1a3b1566) does not exist

List of snapshots as seen from gluster server:

[root@dhcp37-133 glusterfs_packages]# gluster snapshot list

e3d11667-bc2d-4916-831f-d4ee1a3b1566_GMT-2015.07.09-05.52.33
3911868e-9712-4083-adc2-7968ed28881b_GMT-2015.07.09-07.01.38

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/200784

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/200784
Committed: https://git.openstack.org/cgit/openstack/manila/commit/?id=39b92fd9ebd978db16b2367c39582aea72d4f71a
Submitter: Jenkins
Branch: master

commit 39b92fd9ebd978db16b2367c39582aea72d4f71a
Author: Csaba Henk <email address hidden>
Date: Sat Jul 11 03:02:42 2015 +0200

    glusterfs_native: delete_snapshot(): find out real GlusterFS snap name

    So far the delete_snapshot() logic assumed that a GlusterFS snapshot
    exists with exactly the same name as the Manila snapshot id.

    This was a fragile assumption -- both GlusterFS and Manila can
    potentially change how the GlusterFS snapshots are named.
    (And currently we have a problem as GlusterFS has actually changed
    this -- see referred bug about details.)

    Therefore from now on we'll use the weaker assumption that the
    Manila snapshot id is a substring of the backing GlusterFS snapshot
    name. (That's a robust assumption, unlikely to break in the future.)
    The actual GlusterFS snapshot name is found by doing a
    `gluster snapshot list` and grepping for the Manila snapshot id in
    it.

    Change-Id: I40873208c7431e42885bee4db06d6229a202bad6
    Closes-Bug: #1473044

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/kilo
Review: https://review.openstack.org/204993

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/204993
Committed: https://git.openstack.org/cgit/openstack/manila/commit/?id=eec51db6f50bac101e6b9663f1b8286b8c087588
Submitter: Jenkins
Branch: stable/kilo

commit eec51db6f50bac101e6b9663f1b8286b8c087588
Author: Csaba Henk <email address hidden>
Date: Sat Jul 11 03:02:42 2015 +0200

    glusterfs_native: delete_snapshot(): find out real GlusterFS snap name

    So far the delete_snapshot() logic assumed that a GlusterFS snapshot
    exists with exactly the same name as the Manila snapshot id.

    This was a fragile assumption -- both GlusterFS and Manila can
    potentially change how the GlusterFS snapshots are named.
    (And currently we have a problem as GlusterFS has actually changed
    this -- see referred bug about details.)

    Therefore from now on we'll use the weaker assumption that the
    Manila snapshot id is a substring of the backing GlusterFS snapshot
    name. (That's a robust assumption, unlikely to break in the future.)
    The actual GlusterFS snapshot name is found by doing a
    `gluster snapshot list` and grepping for the Manila snapshot id in
    it.

    Change-Id: I40873208c7431e42885bee4db06d6229a202bad6
    Closes-Bug: #1473044
    (cherry picked from commit 39b92fd9ebd978db16b2367c39582aea72d4f71a)