diff --git a/doc/source/library/api_microversion_testing.rst b/doc/source/library/api_microversion_testing.rst
index 0d0b595..b7a4ba8 100644
--- a/doc/source/library/api_microversion_testing.rst
+++ b/doc/source/library/api_microversion_testing.rst
@@ -8,7 +8,7 @@
 ---------------------------------------------
 
 Many of the OpenStack components have implemented API microversions.
-It is important to tests those microversion in Tempest or external plugins.
+It is important to test those microversions in Tempest or external plugins.
 Tempest now provides stable interfaces to support to test the API microversions.
 Based on the microversion range coming from the combination of both configuration
 and each test case, APIs request will be made with selected microversion.
diff --git a/tempest/api/network/test_networks.py b/tempest/api/network/test_networks.py
index d916891..fa1ed6a 100644
--- a/tempest/api/network/test_networks.py
+++ b/tempest/api/network/test_networks.py
@@ -12,10 +12,9 @@
 #    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 #    License for the specific language governing permissions and limitations
 #    under the License.
-import itertools
-
 import netaddr
 import six
+import testtools
 
 from tempest.api.network import base
 from tempest.common import custom_matchers
@@ -376,6 +375,9 @@
 
     @test.attr(type='smoke')
     @test.idempotent_id('af774677-42a9-4e4b-bb58-16fe6a5bc1ec')
+    @test.requires_ext(extension='external-net', service='network')
+    @testtools.skipUnless(CONF.network.public_network_id,
+                          'The public_network_id option must be specified.')
     def test_external_network_visibility(self):
         """Verifies user can see external networks but not subnets."""
         body = self.networks_client.list_networks(**{'router:external': True})
@@ -387,17 +389,12 @@
         self.assertEmpty(nonexternal, "Found non-external networks"
                                       " in filtered list (%s)." % nonexternal)
         self.assertIn(CONF.network.public_network_id, networks)
-
-        subnets_iter = (network['subnets']
-                        for network in body['networks']
-                        if not network['shared'])
-        # subnets_iter is a list (iterator) of lists. This flattens it to a
-        # list of UUIDs
-        public_subnets_iter = itertools.chain(*subnets_iter)
-        body = self.subnets_client.list_subnets()
-        subnets = [sub['id'] for sub in body['subnets']
-                   if sub['id'] in public_subnets_iter]
-        self.assertEmpty(subnets, "Public subnets visible")
+        # only check the public network ID because the other networks may
+        # belong to other tests and their state may have changed during this
+        # test
+        body = self.subnets_client.list_subnets(
+            network_id=CONF.network.public_network_id)
+        self.assertEmpty(body['subnets'], "Public subnets visible")
 
 
 class BulkNetworkOpsTestJSON(base.BaseNetworkTest):
diff --git a/tempest/lib/common/api_version_utils.py b/tempest/lib/common/api_version_utils.py
index 73cd280..1371b3c 100644
--- a/tempest/lib/common/api_version_utils.py
+++ b/tempest/lib/common/api_version_utils.py
@@ -82,7 +82,7 @@
 
 
 def select_request_microversion(test_min_version, cfg_min_version):
-    """Select microversion from test and configuration.
+    """Select microversion from test and configuration min version.
 
     Compare requested microversion and return the maximum
     microversion out of those.
@@ -101,7 +101,7 @@
 def assert_version_header_matches_request(api_microversion_header_name,
                                           api_microversion,
                                           response_header):
-    """Checks API microversion in resposne header
+    """Checks API microversion in response header
 
     Verify whether microversion is present in response header
     and with specified 'api_microversion' value.
diff --git a/tempest/lib/services/compute/base_compute_client.py b/tempest/lib/services/compute/base_compute_client.py
index bbadc8f..9161abb 100644
--- a/tempest/lib/services/compute/base_compute_client.py
+++ b/tempest/lib/services/compute/base_compute_client.py
@@ -23,15 +23,14 @@
 class BaseComputeClient(rest_client.RestClient):
     """Base compute service clients class to support microversion.
 
-    This class adds microversion to API request header if same is set
-    and provide interface to select appropriate JSON schema file for
+    This class adds microversion to API request header if that is set
+    and provides interface to select appropriate JSON schema file for
     response validation.
 
-    :param auth_provider: an auth provider object used to wrap requests in
+    :param auth_provider: An auth provider object used to wrap requests in
                           auth
     :param str service: The service name to use for the catalog lookup
     :param str region: The region to use for the catalog lookup
-                                             request with microversion
     :param kwargs: kwargs required by rest_client.RestClient
     """
 
@@ -79,12 +78,12 @@
         for items in schema_versions_info:
             min_version = api_version_request.APIVersionRequest(items['min'])
             max_version = api_version_request.APIVersionRequest(items['max'])
-            # This is case where self.api_microversion is None, which means
+            # This is case where COMPUTE_MICROVERSION is None, which means
             # request without microversion So select base v2.1 schema.
             if version.is_null() and items['min'] is None:
                 schema = items['schema']
                 break
-            # else select appropriate schema as per self.api_microversion
+            # else select appropriate schema as per COMPUTE_MICROVERSION
             elif version.matches(min_version, max_version):
                 schema = items['schema']
                 break
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index c2b0bf4..8ba5f9a 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -262,7 +262,7 @@
         return server
 
     def create_volume(self, size=None, name=None, snapshot_id=None,
-                      imageRef=None, volume_type=None, wait_on_delete=True):
+                      imageRef=None, volume_type=None):
         if name is None:
             name = data_utils.rand_name(self.__class__.__name__)
         kwargs = {'display_name': name,
@@ -273,17 +273,10 @@
             kwargs.update({'size': size})
         volume = self.volumes_client.create_volume(**kwargs)['volume']
 
-        if wait_on_delete:
-            self.addCleanup(self.volumes_client.wait_for_resource_deletion,
-                            volume['id'])
-            self.addCleanup(self.delete_wrapper,
-                            self.volumes_client.delete_volume, volume['id'])
-        else:
-            self.addCleanup_with_wait(
-                waiter_callable=self.volumes_client.wait_for_resource_deletion,
-                thing_id=volume['id'], thing_id_param='id',
-                cleanup_callable=self.delete_wrapper,
-                cleanup_args=[self.volumes_client.delete_volume, volume['id']])
+        self.addCleanup(self.volumes_client.wait_for_resource_deletion,
+                        volume['id'])
+        self.addCleanup(self.delete_wrapper,
+                        self.volumes_client.delete_volume, volume['id'])
 
         # NOTE(e0ne): Cinder API v2 uses name instead of display_name
         if 'display_name' in volume:
diff --git a/tempest/tests/lib/test_decorators.py b/tempest/tests/lib/test_decorators.py
index 558445d..07b577c 100644
--- a/tempest/tests/lib/test_decorators.py
+++ b/tempest/tests/lib/test_decorators.py
@@ -109,7 +109,7 @@
         t = TestFoo('test_foo')
         if expected_to_skip:
             self.assertRaises(testtools.TestCase.skipException,
-                              t.test_foo())
+                              t.test_foo)
         else:
             try:
                 t.test_foo()