diff --git a/etc/tempest.conf.sample b/etc/tempest.conf.sample
index 9de7492..1f287c8 100644
--- a/etc/tempest.conf.sample
+++ b/etc/tempest.conf.sample
@@ -77,9 +77,6 @@
 # Enables or disables publication of error events. (boolean value)
 #publish_errors = false
 
-# Enables or disables fatal status of deprecations. (boolean value)
-#fatal_deprecations = false
-
 # The format for an instance that is passed with the log message.
 # (string value)
 #instance_format = "[instance: %(uuid)s] "
diff --git a/tempest/tests/common/test_accounts.py b/tempest/tests/common/test_accounts.py
index e713969..f2e8b20 100644
--- a/tempest/tests/common/test_accounts.py
+++ b/tempest/tests/common/test_accounts.py
@@ -292,7 +292,6 @@
              'password': 'p', 'roles': ['role-7', 'role-11'],
              'resources': {'network': 'network-2'}}]
         # Clear previous mock using self.test_accounts
-        self.accounts_mock.cleanUp()
         self.useFixture(mockpatch.Patch(
             'tempest.common.accounts.read_accounts_yaml',
             return_value=test_accounts))
diff --git a/tempest/tests/test_decorators.py b/tempest/tests/test_decorators.py
index e5f51f2..ce3eb7e 100644
--- a/tempest/tests/test_decorators.py
+++ b/tempest/tests/test_decorators.py
@@ -213,8 +213,8 @@
                                        service='compute')
 
     def test_requires_ext_decorator_with_all_ext_enabled(self):
-        # disable fixture so the default (all) is used.
-        self.config_fixture.cleanUp()
+        cfg.CONF.set_default('api_extensions', 'all',
+                             group='compute-feature-enabled')
         self._test_requires_ext_helper(expected_to_skip=False,
                                        extension='random_ext',
                                        service='compute')
diff --git a/tempest/tests/test_tenant_isolation.py b/tempest/tests/test_tenant_isolation.py
index 72a63c3..95008a2 100644
--- a/tempest/tests/test_tenant_isolation.py
+++ b/tempest/tests/test_tenant_isolation.py
@@ -211,20 +211,15 @@
         iso_creds = isolated_creds.IsolatedCreds(name='test class',
                                                  password='fake_password')
         self._mock_assign_user_role()
-        roles_fix = self._mock_list_role()
-        tenant_fix = self._mock_tenant_create('1234', 'fake_prim_tenant')
-        user_fix = self._mock_user_create('1234', 'fake_prim_user')
+        self._mock_list_role()
+        self._mock_tenant_create('1234', 'fake_prim_tenant')
+        self._mock_user_create('1234', 'fake_prim_user')
         iso_creds.get_primary_creds()
-        tenant_fix.cleanUp()
-        user_fix.cleanUp()
-        tenant_fix = self._mock_tenant_create('12345', 'fake_alt_tenant')
-        user_fix = self._mock_user_create('12345', 'fake_alt_user')
+        self._mock_tenant_create('12345', 'fake_alt_tenant')
+        self._mock_user_create('12345', 'fake_alt_user')
         iso_creds.get_alt_creds()
-        tenant_fix.cleanUp()
-        user_fix.cleanUp()
-        roles_fix.cleanUp()
-        tenant_fix = self._mock_tenant_create('123456', 'fake_admin_tenant')
-        user_fix = self._mock_user_create('123456', 'fake_admin_user')
+        self._mock_tenant_create('123456', 'fake_admin_tenant')
+        self._mock_user_create('123456', 'fake_admin_user')
         self._mock_list_roles('123456', 'admin')
         iso_creds.get_admin_creds()
         user_mock = self.patch(
@@ -335,47 +330,36 @@
                                                  password='fake_password')
         # Create primary tenant and network
         self._mock_assign_user_role()
-        roles_fix = self._mock_list_role()
-        user_fix = self._mock_user_create('1234', 'fake_prim_user')
-        tenant_fix = self._mock_tenant_create('1234', 'fake_prim_tenant')
-        net_fix = self._mock_network_create(iso_creds, '1234', 'fake_net')
-        subnet_fix = self._mock_subnet_create(iso_creds, '1234', 'fake_subnet')
-        router_fix = self._mock_router_create('1234', 'fake_router')
+        self._mock_list_role()
+        self._mock_user_create('1234', 'fake_prim_user')
+        self._mock_tenant_create('1234', 'fake_prim_tenant')
+        self._mock_network_create(iso_creds, '1234', 'fake_net')
+        self._mock_subnet_create(iso_creds, '1234', 'fake_subnet')
+        self._mock_router_create('1234', 'fake_router')
         router_interface_mock = self.patch(
             'tempest.services.network.json.network_client.NetworkClientJSON.'
             'add_router_interface_with_subnet_id')
         iso_creds.get_primary_creds()
         router_interface_mock.called_once_with('1234', '1234')
         router_interface_mock.reset_mock()
-        tenant_fix.cleanUp()
-        user_fix.cleanUp()
-        net_fix.cleanUp()
-        subnet_fix.cleanUp()
-        router_fix.cleanUp()
         # Create alternate tenant and network
-        user_fix = self._mock_user_create('12345', 'fake_alt_user')
-        tenant_fix = self._mock_tenant_create('12345', 'fake_alt_tenant')
-        net_fix = self._mock_network_create(iso_creds, '12345', 'fake_alt_net')
-        subnet_fix = self._mock_subnet_create(iso_creds, '12345',
-                                              'fake_alt_subnet')
-        router_fix = self._mock_router_create('12345', 'fake_alt_router')
+        self._mock_user_create('12345', 'fake_alt_user')
+        self._mock_tenant_create('12345', 'fake_alt_tenant')
+        self._mock_network_create(iso_creds, '12345', 'fake_alt_net')
+        self._mock_subnet_create(iso_creds, '12345',
+                                 'fake_alt_subnet')
+        self._mock_router_create('12345', 'fake_alt_router')
         iso_creds.get_alt_creds()
         router_interface_mock.called_once_with('12345', '12345')
         router_interface_mock.reset_mock()
-        tenant_fix.cleanUp()
-        user_fix.cleanUp()
-        net_fix.cleanUp()
-        subnet_fix.cleanUp()
-        router_fix.cleanUp()
-        roles_fix.cleanUp()
         # Create admin tenant and networks
-        user_fix = self._mock_user_create('123456', 'fake_admin_user')
-        tenant_fix = self._mock_tenant_create('123456', 'fake_admin_tenant')
-        net_fix = self._mock_network_create(iso_creds, '123456',
-                                            'fake_admin_net')
-        subnet_fix = self._mock_subnet_create(iso_creds, '123456',
-                                              'fake_admin_subnet')
-        router_fix = self._mock_router_create('123456', 'fake_admin_router')
+        self._mock_user_create('123456', 'fake_admin_user')
+        self._mock_tenant_create('123456', 'fake_admin_tenant')
+        self._mock_network_create(iso_creds, '123456',
+                                  'fake_admin_net')
+        self._mock_subnet_create(iso_creds, '123456',
+                                 'fake_admin_subnet')
+        self._mock_router_create('123456', 'fake_admin_router')
         self._mock_list_roles('123456', 'admin')
         iso_creds.get_admin_creds()
         self.patch('tempest.services.identity.v2.json.identity_client.'