Merge "Allow configuration of a back end specific availability zone"

doc/source/admin/shared-file-systems-share-replication.rst

@@ -122,7 +122,7 @@ The following examples have been implemented with the ZFSonLinux driver that
 is a reference implementation in the Shared File Systems service. It operates
 in ``driver_handles_share_servers=False`` mode and supports the ``readable``
 type of replication. In the example, we assume a configuration of two
-Availability Zones (configuration option: ``storage_availability_zone``),
+Availability Zones [1]_,
 called `availability_zone_1` and `availability_zone_2`.
 
 Multiple availability zones are not necessary to use the replication feature.
@@ -598,3 +598,14 @@ replica's ID to delete a share replica.
 .. note::
    You cannot delete the last ``active`` replica with this command. You should
    use the :command:`manila delete` command to remove the share.
+
+
+.. [1] When running in a multi-backend configuration, until the Stein
+       release, deployers could only configure one Availability Zone per manila
+       configuration file. This is achieved with the option
+       ``storage_availability_zone`` defined under the ``[DEFAULT]`` section.
+
+       Beyond the Stein release, the option ``backend_availability_zone``
+       can be specified in each back end stanza. The value of this
+       configuration option will override any configuration of the
+       ``storage_availability_zone`` from the ``[DEFAULT]`` section.

doc/source/contributor/share_replication.rst

@@ -56,8 +56,9 @@ pools, manila would allow for replication between two pools on the same
 backend.
 
 The ``replication_domain`` option is meant to be used in conjunction with the
-``storage_availability_zone`` option to utilize this solution for Data
-Protection/Disaster Recovery.
+``storage_availability_zone`` (or back end specific
+``backend_availability_zone``) option to utilize
+this solution for Data Protection/Disaster Recovery.
 
 
 Replication types

manila/manager.py

@@ -91,6 +91,7 @@ class Manager(base.Base, PeriodicTasks):
             host = CONF.host
         self.host = host
         self.additional_endpoints = []
+        self.availability_zone = CONF.storage_availability_zone
         super(Manager, self).__init__(db_driver)
 
     def periodic_tasks(self, context, raise_on_error=False):

manila/service.py

@@ -92,6 +92,7 @@ class Service(service.Service):
         self.manager = manager_class(host=self.host,
                                      service_name=service_name,
                                      *args, **kwargs)
+        self.availability_zone = self.manager.availability_zone
         self.report_interval = report_interval
         self.periodic_interval = periodic_interval
         self.periodic_fuzzy_delay = periodic_fuzzy_delay
@@ -145,13 +146,14 @@ class Service(service.Service):
             self.timers.append(periodic)
 
     def _create_service_ref(self, context):
-        zone = CONF.storage_availability_zone
-        service_ref = db.service_create(context,
-                                        {'host': self.host,
-                                         'binary': self.binary,
-                                         'topic': self.topic,
-                                         'report_count': 0,
-                                         'availability_zone': zone})
+        service_args = {
+            'host': self.host,
+            'binary': self.binary,
+            'topic': self.topic,
+            'report_count': 0,
+            'availability_zone': self.availability_zone
+        }
+        service_ref = db.service_create(context, service_args)
         self.service_id = service_ref['id']
 
     def __getattr__(self, key):
@@ -244,7 +246,6 @@ class Service(service.Service):
     def report_state(self):
         """Update the state of this service in the datastore."""
         ctxt = context.get_admin_context()
-        zone = CONF.storage_availability_zone
         state_catalog = {}
         try:
             try:
@@ -256,8 +257,9 @@ class Service(service.Service):
                 service_ref = db.service_get(ctxt, self.service_id)
 
             state_catalog['report_count'] = service_ref['report_count'] + 1
-            if zone != service_ref['availability_zone']['name']:
-                state_catalog['availability_zone'] = zone
+            if (self.availability_zone !=
+                    service_ref['availability_zone']['name']):
+                state_catalog['availability_zone'] = self.availability_zone
 
             db.service_update(ctxt,
                               self.service_id, state_catalog)

manila/share/driver.py

@@ -126,6 +126,11 @@ share_opts = [
              "replication between each other. If this option is not "
              "specified in the group, it means that replication is not "
              "enabled on the backend."),
+    cfg.StrOpt('backend_availability_zone',
+               default=None,
+               help='Availability zone for this share backend. If not set, '
+                    'the ``storage_availability_zone`` option from the '
+                    '``[DEFAULT]`` section is used.'),
     cfg.StrOpt('filter_function',
                help='String representation for an equation that will be '
                     'used to filter hosts.'),

manila/share/drivers/service_instance.py

@@ -219,6 +219,9 @@ class ServiceInstanceManager(object):
         self.max_time_to_build_instance = self.get_config_option(
             "max_time_to_build_instance")
 
+        self.availability_zone = self.get_config_option(
+            'backend_availability_zone') or CONF.storage_availability_zone
+
         if self.get_config_option("driver_handles_share_servers"):
             self.path_to_public_key = self.get_config_option(
                 "path_to_public_key")
@@ -564,7 +567,7 @@ class ServiceInstanceManager(object):
                 flavor=self.get_config_option("service_instance_flavor_id"),
                 key_name=key_name,
                 nics=network_data['nics'],
-                availability_zone=CONF.storage_availability_zone,
+                availability_zone=self.availability_zone,
                 **create_kwargs)
 
             fail_safe_data['instance_id'] = service_instance['id']

manila/share/manager.py

@@ -239,6 +239,12 @@ class ShareManager(manager.SchedulerDependentManager):
             configuration=self.configuration,
         )
 
+        backend_availability_zone = self.driver.configuration.safe_get(
+            'backend_availability_zone')
+        self.availability_zone = (
+            backend_availability_zone or CONF.storage_availability_zone
+        )
+
         self.access_helper = access.ShareInstanceAccess(self.db, self.driver)
         self.snapshot_access_helper = (
             snapshot_access.ShareSnapshotInstanceAccess(self.db, self.driver))
@@ -1659,7 +1665,7 @@ class ShareManager(manager.SchedulerDependentManager):
         if not share_instance['availability_zone']:
             share_instance = self.db.share_instance_update(
                 context, share_instance_id,
-                {'availability_zone': CONF.storage_availability_zone},
+                {'availability_zone': self.availability_zone},
                 with_share_data=True
             )
 
@@ -1834,7 +1840,7 @@ class ShareManager(manager.SchedulerDependentManager):
         if not share_replica['availability_zone']:
             share_replica = self.db.share_replica_update(
                 context, share_replica['id'],
-                {'availability_zone': CONF.storage_availability_zone},
+                {'availability_zone': self.availability_zone},
                 with_share_data=True
             )
 
@@ -2400,7 +2406,7 @@ class ShareManager(manager.SchedulerDependentManager):
             share_update.update({
                 'status': constants.STATUS_AVAILABLE,
                 'launched_at': timeutils.utcnow(),
-                'availability_zone': CONF.storage_availability_zone,
+                'availability_zone': self.availability_zone,
             })
 
             # If the share was managed with `replication_type` extra-spec, the
@@ -3865,7 +3871,7 @@ class ShareManager(manager.SchedulerDependentManager):
     def _get_az_for_share_group(self, context, share_group_ref):
         if not share_group_ref['availability_zone_id']:
             return self.db.availability_zone_get(
-                context, CONF.storage_availability_zone)['id']
+                context, self.availability_zone)['id']
         return share_group_ref['availability_zone_id']
 
     @utils.require_driver_initialized

manila/tests/share/drivers/test_service_instance.py

@@ -75,6 +75,8 @@ def fake_get_config_option(key):
         return None
     elif key == 'admin_subnet_id':
         return None
+    elif key == 'backend_availability_zone':
+        return None
     else:
         return mock.Mock()
 

manila/tests/share/test_manager.py

@@ -990,7 +990,7 @@ class ShareManagerTestCase(test.TestCase):
         replica_2 = fake_replica(id='fake2')
         self.mock_object(db, 'share_replicas_get_all_by_share',
                          mock.Mock(return_value=[replica, replica_2]))
-        manager.CONF.set_default('storage_availability_zone', 'fake_az')
+        self.share_manager.availability_zone = 'fake_az'
         fake_access_rules = [{'id': '1'}, {'id': '2'}, {'id': '3'}]
         self.mock_object(db, 'share_replica_get',
                          mock.Mock(return_value=replica))

releasenotes/notes/per-backend-az-590c68be0e2cb4bd.yaml

@@ -0,0 +1,14 @@
+---
+features:
+  - |
+    Availability zones may now be configured per backend in a multi-backend
+    configuration. Individual back end sections can now have the configuration
+    option ``backend_availability_zone`` set. If set, this value will override
+    the ``storage_availability_zone`` option from the [DEFAULT] section.
+upgrade:
+  - The ``storage_availability_zone`` option can now be overridden per
+    backend by using the ``backend_availability_zone`` option within the
+    backend stanza. This allows enabling multiple storage backends that may
+    be deployed in different AZs in the same ``manila.conf`` file if
+    desired, simplifying service architecture around the Share Replication
+    feature.