diff --git a/tempest/api/baremetal/admin/base.py b/tempest/api/baremetal/admin/base.py
index d7d2efe..80b69b9 100644
--- a/tempest/api/baremetal/admin/base.py
+++ b/tempest/api/baremetal/admin/base.py
@@ -98,8 +98,7 @@
     @classmethod
     @creates('chassis')
     def create_chassis(cls, description=None, expect_errors=False):
-        """
-        Wrapper utility for creating test chassis.
+        """Wrapper utility for creating test chassis.
 
         :param description: A description of the chassis. if not supplied,
             a random value will be generated.
@@ -114,8 +113,7 @@
     @creates('node')
     def create_node(cls, chassis_id, cpu_arch='x86', cpus=8, local_gb=10,
                     memory_mb=4096):
-        """
-        Wrapper utility for creating test baremetal nodes.
+        """Wrapper utility for creating test baremetal nodes.
 
         :param cpu_arch: CPU architecture of the node. Default: x86.
         :param cpus: Number of CPUs. Default: 8.
@@ -134,8 +132,7 @@
     @classmethod
     @creates('port')
     def create_port(cls, node_id, address, extra=None, uuid=None):
-        """
-        Wrapper utility for creating test ports.
+        """Wrapper utility for creating test ports.
 
         :param address: MAC address of the port.
         :param extra: Meta data of the port. If not supplied, an empty
@@ -152,8 +149,7 @@
 
     @classmethod
     def delete_chassis(cls, chassis_id):
-        """
-        Deletes a chassis having the specified UUID.
+        """Deletes a chassis having the specified UUID.
 
         :param uuid: The unique identifier of the chassis.
         :return: Server response.
@@ -169,8 +165,7 @@
 
     @classmethod
     def delete_node(cls, node_id):
-        """
-        Deletes a node having the specified UUID.
+        """Deletes a node having the specified UUID.
 
         :param uuid: The unique identifier of the node.
         :return: Server response.
@@ -186,8 +181,7 @@
 
     @classmethod
     def delete_port(cls, port_id):
-        """
-        Deletes a port having the specified UUID.
+        """Deletes a port having the specified UUID.
 
         :param uuid: The unique identifier of the port.
         :return: Server response.
diff --git a/tempest/api/compute/admin/test_baremetal_nodes.py b/tempest/api/compute/admin/test_baremetal_nodes.py
index 2599d86..b764483 100644
--- a/tempest/api/compute/admin/test_baremetal_nodes.py
+++ b/tempest/api/compute/admin/test_baremetal_nodes.py
@@ -20,9 +20,7 @@
 
 
 class BaremetalNodesAdminTestJSON(base.BaseV2ComputeAdminTest):
-    """
-    Tests Baremetal API
-    """
+    """Tests Baremetal API"""
 
     @classmethod
     def resource_setup(cls):
diff --git a/tempest/api/compute/admin/test_live_migration.py b/tempest/api/compute/admin/test_live_migration.py
index cfae772..7c4c30c 100644
--- a/tempest/api/compute/admin/test_live_migration.py
+++ b/tempest/api/compute/admin/test_live_migration.py
@@ -36,7 +36,7 @@
                         "not available" % cls.__name__)
             raise cls.skipException(skip_msg)
         if CONF.compute.min_compute_nodes < 2:
-            raise cls.skipTest(
+            raise cls.skipException(
                 "Less than 2 compute nodes, skipping migration test.")
 
     @classmethod
diff --git a/tempest/api/compute/admin/test_servers.py b/tempest/api/compute/admin/test_servers.py
index dfaa5d5..993d39e 100644
--- a/tempest/api/compute/admin/test_servers.py
+++ b/tempest/api/compute/admin/test_servers.py
@@ -22,10 +22,7 @@
 
 
 class ServersAdminTestJSON(base.BaseV2ComputeAdminTest):
-
-    """
-    Tests Servers API using admin privileges
-    """
+    """Tests Servers API using admin privileges"""
 
     _host_key = 'OS-EXT-SRV-ATTR:host'
 
diff --git a/tempest/api/compute/admin/test_services_negative.py b/tempest/api/compute/admin/test_services_negative.py
index 0c81ccb..e57401a 100644
--- a/tempest/api/compute/admin/test_services_negative.py
+++ b/tempest/api/compute/admin/test_services_negative.py
@@ -19,10 +19,7 @@
 
 
 class ServicesAdminNegativeTestJSON(base.BaseV2ComputeAdminTest):
-
-    """
-    Tests Services API. List and Enable/Disable require admin privileges.
-    """
+    """Tests Services API. List and Enable/Disable require admin privileges."""
 
     @classmethod
     def setup_clients(cls):
diff --git a/tempest/api/data_processing/base.py b/tempest/api/data_processing/base.py
index 5d78539..4e88f65 100644
--- a/tempest/api/data_processing/base.py
+++ b/tempest/api/data_processing/base.py
@@ -399,6 +399,7 @@
     @classmethod
     def _get_default_version(cls):
         """Returns the default plugin version used for testing.
+
         This is gathered separately from the plugin to allow
         the usage of plugin name in skip_checks. This method is
         rather invoked into resource_setup, which allows API calls
@@ -439,6 +440,7 @@
     @classmethod
     def get_cluster_template(cls, node_group_template_ids=None):
         """Returns a cluster template for the default plugin.
+
         node_group_template_defined contains the type and ID of pre-defined
         node group templates that have to be used in the cluster template
         (instead of dynamically defining them with 'node_processes').
diff --git a/tempest/api/data_processing/test_cluster_templates.py b/tempest/api/data_processing/test_cluster_templates.py
index 42cbd14..dfd8e27 100644
--- a/tempest/api/data_processing/test_cluster_templates.py
+++ b/tempest/api/data_processing/test_cluster_templates.py
@@ -19,9 +19,9 @@
 
 
 class ClusterTemplateTest(dp_base.BaseDataProcessingTest):
-    """Link to the API documentation is http://docs.openstack.org/developer/
-    sahara/restapi/rest_api_v1.0.html#cluster-templates
-    """
+    # Link to the API documentation is http://docs.openstack.org/developer/
+    # sahara/restapi/rest_api_v1.0.html#cluster-templates
+
     @classmethod
     def skip_checks(cls):
         super(ClusterTemplateTest, cls).skip_checks()
diff --git a/tempest/api/data_processing/test_job_binaries.py b/tempest/api/data_processing/test_job_binaries.py
index 98b7e24..a47ddbc 100644
--- a/tempest/api/data_processing/test_job_binaries.py
+++ b/tempest/api/data_processing/test_job_binaries.py
@@ -18,9 +18,9 @@
 
 
 class JobBinaryTest(dp_base.BaseDataProcessingTest):
-    """Link to the API documentation is http://docs.openstack.org/developer/
-    sahara/restapi/rest_api_v1.1_EDP.html#job-binaries
-    """
+    # Link to the API documentation is http://docs.openstack.org/developer/
+    # sahara/restapi/rest_api_v1.1_EDP.html#job-binaries
+
     @classmethod
     def resource_setup(cls):
         super(JobBinaryTest, cls).resource_setup()
diff --git a/tempest/api/data_processing/test_job_binary_internals.py b/tempest/api/data_processing/test_job_binary_internals.py
index 6919fa5..b4f0769 100644
--- a/tempest/api/data_processing/test_job_binary_internals.py
+++ b/tempest/api/data_processing/test_job_binary_internals.py
@@ -18,9 +18,9 @@
 
 
 class JobBinaryInternalTest(dp_base.BaseDataProcessingTest):
-    """Link to the API documentation is http://docs.openstack.org/developer/
-    sahara/restapi/rest_api_v1.1_EDP.html#job-binary-internals
-    """
+    # Link to the API documentation is http://docs.openstack.org/developer/
+    # sahara/restapi/rest_api_v1.1_EDP.html#job-binary-internals
+
     @classmethod
     def resource_setup(cls):
         super(JobBinaryInternalTest, cls).resource_setup()
diff --git a/tempest/api/data_processing/test_jobs.py b/tempest/api/data_processing/test_jobs.py
index 7798056..8503320 100644
--- a/tempest/api/data_processing/test_jobs.py
+++ b/tempest/api/data_processing/test_jobs.py
@@ -18,9 +18,9 @@
 
 
 class JobTest(dp_base.BaseDataProcessingTest):
-    """Link to the API documentation is http://docs.openstack.org/developer/
-    sahara/restapi/rest_api_v1.1_EDP.html#jobs
-    """
+    # NOTE: Link to the API documentation: http://docs.openstack.org/developer/
+    # sahara/restapi/rest_api_v1.1_EDP.html#jobs
+
     @classmethod
     def resource_setup(cls):
         super(JobTest, cls).resource_setup()
diff --git a/tempest/api/identity/admin/v2/test_tokens.py b/tempest/api/identity/admin/v2/test_tokens.py
index e808990..0e7a480 100644
--- a/tempest/api/identity/admin/v2/test_tokens.py
+++ b/tempest/api/identity/admin/v2/test_tokens.py
@@ -52,8 +52,9 @@
 
     @test.idempotent_id('25ba82ee-8a32-4ceb-8f50-8b8c71e8765e')
     def test_rescope_token(self):
-        """An unscoped token can be requested, that token can be used to
-           request a scoped token.
+        """An unscoped token can be requested
+
+        That token can be used to request a scoped token.
         """
 
         # Create a user.
diff --git a/tempest/api/identity/admin/v3/test_domains_negative.py b/tempest/api/identity/admin/v3/test_domains_negative.py
index 910fe5f..9eb3149 100644
--- a/tempest/api/identity/admin/v3/test_domains_negative.py
+++ b/tempest/api/identity/admin/v3/test_domains_negative.py
@@ -52,3 +52,21 @@
         d_name = 'a' * 65
         self.assertRaises(lib_exc.BadRequest, self.client.create_domain,
                           d_name)
+
+    @test.attr(type=['negative'])
+    @test.idempotent_id('43781c07-764f-4cf2-a405-953c1916f605')
+    def test_delete_non_existent_domain(self):
+        # Attempt to delete a non existent domain should fail
+        self.assertRaises(lib_exc.NotFound, self.client.delete_domain,
+                          data_utils.rand_uuid_hex())
+
+    @test.attr(type=['negative'])
+    @test.idempotent_id('e6f9e4a2-4f36-4be8-bdbc-4e199ae29427')
+    def test_domain_create_duplicate(self):
+        domain_name = data_utils.rand_name('domain-dup')
+        domain = self.client.create_domain(domain_name)['domain']
+        domain_id = domain['id']
+        self.addCleanup(self.delete_domain, domain_id)
+        # Domain name should be unique
+        self.assertRaises(
+            lib_exc.Conflict, self.client.create_domain, domain_name)
diff --git a/tempest/api/image/admin/v2/test_images.py b/tempest/api/image/admin/v2/test_images.py
index 09877ba..01838b6 100644
--- a/tempest/api/image/admin/v2/test_images.py
+++ b/tempest/api/image/admin/v2/test_images.py
@@ -26,10 +26,8 @@
 
 
 class BasicAdminOperationsImagesTest(base.BaseV2ImageAdminTest):
+    """Here we test admin operations of images"""
 
-    """
-    Here we test admin operations of images
-    """
     @testtools.skipUnless(CONF.image_feature_enabled.deactivate_image,
                           'deactivate-image is not available.')
     @test.idempotent_id('951ebe01-969f-4ea9-9898-8a3f1f442ab0')
diff --git a/tempest/api/image/v1/test_images.py b/tempest/api/image/v1/test_images.py
index d4dbfcd..64f3174 100644
--- a/tempest/api/image/v1/test_images.py
+++ b/tempest/api/image/v1/test_images.py
@@ -100,10 +100,7 @@
 
 
 class ListImagesTest(base.BaseV1ImageTest):
-
-    """
-    Here we test the listing of image information
-    """
+    """Here we test the listing of image information"""
 
     @classmethod
     def resource_setup(cls):
@@ -131,10 +128,8 @@
 
     @classmethod
     def _create_remote_image(cls, name, container_format, disk_format):
-        """
-        Create a new remote image and return the ID of the newly-registered
-        image
-        """
+        """Create a new remote image and return newly-registered image-id"""
+
         name = 'New Remote Image %s' % name
         location = CONF.image.http_image
         image = cls.create_image(name=name,
@@ -148,9 +143,9 @@
     @classmethod
     def _create_standard_image(cls, name, container_format,
                                disk_format, size):
-        """
-        Create a new standard image and return the ID of the newly-registered
-        image. Note that the size of the new image is a random number between
+        """Create a new standard image and return newly-registered image-id
+
+        Note that the size of the new image is a random number between
         1024 and 4096
         """
         image_file = moves.cStringIO(data_utils.random_bytes(size))
@@ -241,10 +236,8 @@
     @classmethod
     def _create_standard_image(cls, name, container_format,
                                disk_format, size):
-        """
-        Create a new standard image and return the ID of the newly-registered
-        image.
-        """
+        """Create a new standard image and return newly-registered image-id"""
+
         image_file = moves.cStringIO(data_utils.random_bytes(size))
         name = 'New Standard Image %s' % name
         image = cls.create_image(name=name,
diff --git a/tempest/api/image/v2/test_images.py b/tempest/api/image/v2/test_images.py
index bacf211..936eadf 100644
--- a/tempest/api/image/v2/test_images.py
+++ b/tempest/api/image/v2/test_images.py
@@ -29,17 +29,15 @@
 
 
 class BasicOperationsImagesTest(base.BaseV2ImageTest):
-    """
-    Here we test the basic operations of images
-    """
+    """Here we test the basic operations of images"""
 
     @test.attr(type='smoke')
     @test.idempotent_id('139b765e-7f3d-4b3d-8b37-3ca3876ee318')
     def test_register_upload_get_image_file(self):
+        """Here we test these functionalities
 
-        """
-        Here we test these functionalities - Register image,
-        upload the image file, get image and get image file api's
+        Register image, upload the image file, get image and get image
+        file api's
         """
 
         uuid = '00000000-1111-2222-3333-444455556666'
@@ -135,9 +133,7 @@
 
 
 class ListImagesTest(base.BaseV2ImageTest):
-    """
-    Here we test the listing of image information
-    """
+    """Here we test the listing of image information"""
 
     @classmethod
     def resource_setup(cls):
@@ -158,9 +154,9 @@
 
     @classmethod
     def _create_standard_image(cls, container_format, disk_format):
-        """
-        Create a new standard image and return the ID of the newly-registered
-        image. Note that the size of the new image is a random number between
+        """Create a new standard image and return the newly-registered image-id
+
+        Note that the size of the new image is a random number between
         1024 and 4096
         """
         size = random.randint(1024, 4096)
@@ -176,9 +172,8 @@
         return image_id
 
     def _list_by_param_value_and_assert(self, params):
-        """
-        Perform list action with given params and validates result.
-        """
+        """Perform list action with given params and validates result."""
+
         images_list = self.client.list_images(params=params)['images']
         # Validating params of fetched images
         for image in images_list:
diff --git a/tempest/api/image/v2/test_images_metadefs_namespaces.py b/tempest/api/image/v2/test_images_metadefs_namespaces.py
index 21247b1..d089c84 100644
--- a/tempest/api/image/v2/test_images_metadefs_namespaces.py
+++ b/tempest/api/image/v2/test_images_metadefs_namespaces.py
@@ -20,9 +20,8 @@
 
 
 class MetadataNamespacesTest(base.BaseV2ImageTest):
-    """
-    Here we will test the Metadata definition Namespaces basic functionality.
-    """
+    """Test the Metadata definition Namespaces basic functionality"""
+
     @test.idempotent_id('319b765e-7f3d-4b3d-8b37-3ca3876ee768')
     def test_basic_metadata_definition_namespaces(self):
         # get the available resource types and use one resource_type
diff --git a/tempest/api/image/v2/test_images_negative.py b/tempest/api/image/v2/test_images_negative.py
index c5c5e8b..71c8c7a 100644
--- a/tempest/api/image/v2/test_images_negative.py
+++ b/tempest/api/image/v2/test_images_negative.py
@@ -24,8 +24,7 @@
 
 class ImagesNegativeTest(base.BaseV2ImageTest):
 
-    """
-    here we have -ve tests for show_image and delete_image api
+    """here we have -ve tests for show_image and delete_image api
 
     Tests
         ** get non-existent image
diff --git a/tempest/api/messaging/base.py b/tempest/api/messaging/base.py
index 64a7fd5..39dc7c3 100644
--- a/tempest/api/messaging/base.py
+++ b/tempest/api/messaging/base.py
@@ -26,8 +26,7 @@
 
 class BaseMessagingTest(test.BaseTestCase):
 
-    """
-    Base class for the Messaging tests that use the Tempest Zaqar REST client
+    """Base class for the Messaging (Zaqar) tests
 
     It is assumed that the following option is defined in the
     [service_available] section of etc/tempest.conf
diff --git a/tempest/api/object_storage/base.py b/tempest/api/object_storage/base.py
index 41a7d65..2621581 100644
--- a/tempest/api/object_storage/base.py
+++ b/tempest/api/object_storage/base.py
@@ -90,10 +90,8 @@
                 pass
 
     def assertHeaders(self, resp, target, method):
-        """
-        Common method to check the existence and the format of common response
-        headers
-        """
+        """Check the existence and the format of response headers"""
+
         self.assertThat(resp, custom_matchers.ExistsAllResponseHeaders(
                         target, method))
         self.assertThat(resp, custom_matchers.AreAllWellFormatted())
diff --git a/tempest/api/object_storage/test_account_quotas.py b/tempest/api/object_storage/test_account_quotas.py
index 78707d8..0f6a330 100644
--- a/tempest/api/object_storage/test_account_quotas.py
+++ b/tempest/api/object_storage/test_account_quotas.py
@@ -92,8 +92,7 @@
     @test.idempotent_id('63f51f9f-5f1d-4fc6-b5be-d454d70949d6')
     @test.requires_ext(extension='account_quotas', service='object')
     def test_admin_modify_quota(self):
-        """Test that the ResellerAdmin is able to modify and remove the quota
-        on a user's account.
+        """Test ResellerAdmin can modify/remove the quota on a user's account
 
         Using the account client, the test modifies the quota
         successively to:
diff --git a/tempest/api/object_storage/test_account_quotas_negative.py b/tempest/api/object_storage/test_account_quotas_negative.py
index 2bf331a..aee17d3 100644
--- a/tempest/api/object_storage/test_account_quotas_negative.py
+++ b/tempest/api/object_storage/test_account_quotas_negative.py
@@ -83,9 +83,7 @@
     @test.idempotent_id('d1dc5076-555e-4e6d-9697-28f1fe976324')
     @test.requires_ext(extension='account_quotas', service='object')
     def test_user_modify_quota(self):
-        """Test that a user is not able to modify or remove a quota on
-        its account.
-        """
+        """Test that a user cannot modify or remove a quota on its account."""
 
         # Not able to remove quota
         self.assertRaises(lib_exc.Forbidden,
diff --git a/tempest/api/orchestration/stacks/test_non_empty_stack.py b/tempest/api/orchestration/stacks/test_non_empty_stack.py
index e37587c..4bc2c17 100644
--- a/tempest/api/orchestration/stacks/test_non_empty_stack.py
+++ b/tempest/api/orchestration/stacks/test_non_empty_stack.py
@@ -91,8 +91,7 @@
 
     @test.idempotent_id('c951d55e-7cce-4c1f-83a0-bad735437fa6')
     def test_list_resources(self):
-        """Getting list of created resources for the stack should be possible.
-        """
+        """Get list of created resources for the stack should be possible."""
         resources = self.list_resources(self.stack_identifier)
         self.assertEqual({self.resource_name: self.resource_type}, resources)
 
diff --git a/tempest/api/telemetry/base.py b/tempest/api/telemetry/base.py
index 8f07614..81f00ec 100644
--- a/tempest/api/telemetry/base.py
+++ b/tempest/api/telemetry/base.py
@@ -112,8 +112,8 @@
         super(BaseTelemetryTest, cls).resource_cleanup()
 
     def await_samples(self, metric, query):
-        """
-        This method is to wait for sample to add it to database.
+        """This method is to wait for sample to add it to database.
+
         There are long time delays when using Postgresql (or Mysql)
         database as ceilometer backend
         """
diff --git a/tempest/api/telemetry/test_alarming_api_negative.py b/tempest/api/telemetry/test_alarming_api_negative.py
index 7d5a0bf..06753b0 100644
--- a/tempest/api/telemetry/test_alarming_api_negative.py
+++ b/tempest/api/telemetry/test_alarming_api_negative.py
@@ -21,8 +21,8 @@
 
 
 class TelemetryAlarmingNegativeTest(base.BaseTelemetryTest):
-    """here we have negative tests for show_alarm, update_alarm, show_alarm_history
-       Tests
+    """Negative tests for show_alarm, update_alarm, show_alarm_history tests
+
         ** show non-existent alarm
         ** show the deleted alarm
         ** delete deleted alarm
diff --git a/tempest/api/volume/admin/test_volume_services.py b/tempest/api/volume/admin/test_volume_services.py
index 74fffb9..6692594 100644
--- a/tempest/api/volume/admin/test_volume_services.py
+++ b/tempest/api/volume/admin/test_volume_services.py
@@ -18,8 +18,8 @@
 
 
 class VolumesServicesV2TestJSON(base.BaseVolumeAdminTest):
-    """
-    Tests Volume Services API.
+    """Tests Volume Services API.
+
     volume service list requires admin privileges.
     """
 
diff --git a/tempest/api/volume/test_availability_zone.py b/tempest/api/volume/test_availability_zone.py
index 366b8d2..fe51375 100644
--- a/tempest/api/volume/test_availability_zone.py
+++ b/tempest/api/volume/test_availability_zone.py
@@ -18,10 +18,7 @@
 
 
 class AvailabilityZoneV2TestJSON(base.BaseVolumeTest):
-
-    """
-    Tests Availability Zone V2 API List
-    """
+    """Tests Availability Zone V2 API List"""
 
     @classmethod
     def setup_clients(cls):
diff --git a/tempest/api/volume/test_volumes_list.py b/tempest/api/volume/test_volumes_list.py
index 620366a..b776494 100644
--- a/tempest/api/volume/test_volumes_list.py
+++ b/tempest/api/volume/test_volumes_list.py
@@ -26,14 +26,11 @@
 
 
 class VolumesV2ListTestJSON(base.BaseVolumeTest):
-
-    """
-    This test creates a number of 1G volumes. To run successfully,
-    ensure that the backing file for the volume group that Nova uses
-    has space for at least 3 1G volumes!
-    If you are running a Devstack environment, ensure that the
-    VOLUME_BACKING_FILE_SIZE is at least 4G in your localrc
-    """
+    # NOTE: This test creates a number of 1G volumes. To run successfully,
+    # ensure that the backing file for the volume group that Nova uses
+    # has space for at least 3 1G volumes!
+    # If you are running a Devstack environment, ensure that the
+    # VOLUME_BACKING_FILE_SIZE is at least 4G in your localrc
 
     VOLUME_FIELDS = ('id', 'name')
 
@@ -83,10 +80,7 @@
         super(VolumesV2ListTestJSON, cls).resource_cleanup()
 
     def _list_by_param_value_and_assert(self, params, with_detail=False):
-        """
-        Perform list or list_details action with given params
-        and validates result.
-        """
+        """list or list_details with given params and validates result"""
         if with_detail:
             fetched_vol_list = \
                 self.client.list_volumes(detail=True, params=params)['volumes']
diff --git a/tempest/api/volume/test_volumes_snapshots.py b/tempest/api/volume/test_volumes_snapshots.py
index 9866da3..856adcc 100644
--- a/tempest/api/volume/test_volumes_snapshots.py
+++ b/tempest/api/volume/test_volumes_snapshots.py
@@ -43,10 +43,8 @@
         self.volumes_client.wait_for_volume_status(volume_id, 'available')
 
     def _list_by_param_values_and_assert(self, params, with_detail=False):
-        """
-        Perform list or list_details action with given params
-        and validates result.
-        """
+        """list or list_details with given params and validates result."""
+
         if with_detail:
             fetched_snap_list = self.snapshots_client.list_snapshots(
                 detail=True, params=params)['snapshots']
diff --git a/tempest/api/volume/v2/test_volumes_list.py b/tempest/api/volume/v2/test_volumes_list.py
index 94a9d16..6568627 100644
--- a/tempest/api/volume/v2/test_volumes_list.py
+++ b/tempest/api/volume/v2/test_volumes_list.py
@@ -21,9 +21,7 @@
 
 
 class VolumesV2ListTestJSON(base.BaseVolumeTest):
-
-    """
-    volumes v2 specific tests.
+    """volumes v2 specific tests.
 
     This test creates a number of 1G volumes. To run successfully,
     ensure that the backing file for the volume group that Nova uses