diff --git a/neutron/plugins/ibm/agent/sdnve_neutron_agent.py b/neutron/plugins/ibm/agent/sdnve_neutron_agent.py
index 4f6579071f..a30f91170e 100644
--- a/neutron/plugins/ibm/agent/sdnve_neutron_agent.py
+++ b/neutron/plugins/ibm/agent/sdnve_neutron_agent.py
@@ -35,11 +35,12 @@ from neutron.common import utils as n_utils
 from neutron import context
 from neutron.openstack.common import log as logging
 from neutron.openstack.common import loopingcall
-from neutron.plugins.ibm.common import config  # noqa
 from neutron.plugins.ibm.common import constants
 
 
 LOG = logging.getLogger(__name__)
+cfg.CONF.import_group('SDNVE', 'neutron.plugins.ibm.common.config')
+cfg.CONF.import_group('SDNVE_AGENT', 'neutron.plugins.ibm.common.config')
 
 
 class SdnvePluginApi(agent_rpc.PluginApi):
@@ -230,7 +231,6 @@ class SdnveNeutronAgent(n_rpc.RpcCallback):
 
 
 def create_agent_config_map(config):
-
     interface_mappings = n_utils.parse_mappings(
         config.SDNVE.interface_mappings)
 
diff --git a/neutron/plugins/ofagent/agent/ofa_neutron_agent.py b/neutron/plugins/ofagent/agent/ofa_neutron_agent.py
index 8c4b98a3e3..5dd4c52b43 100644
--- a/neutron/plugins/ofagent/agent/ofa_neutron_agent.py
+++ b/neutron/plugins/ofagent/agent/ofa_neutron_agent.py
@@ -52,11 +52,11 @@ from neutron.plugins.ofagent.agent import constants as ofa_const
 from neutron.plugins.ofagent.agent import flows
 from neutron.plugins.ofagent.agent import ports
 from neutron.plugins.ofagent.agent import tables
-from neutron.plugins.ofagent.common import config  # noqa
 from neutron.plugins.openvswitch.common import constants
 
 
 LOG = logging.getLogger(__name__)
+cfg.CONF.import_group('AGENT', 'neutron.plugins.ofagent.common.config')
 
 
 # A class to represent a VIF (i.e., a port that has 'iface-id' and 'vif-mac'
diff --git a/neutron/plugins/openvswitch/agent/ovs_neutron_agent.py b/neutron/plugins/openvswitch/agent/ovs_neutron_agent.py
index 08cbbb64c5..76626e9f38 100644
--- a/neutron/plugins/openvswitch/agent/ovs_neutron_agent.py
+++ b/neutron/plugins/openvswitch/agent/ovs_neutron_agent.py
@@ -45,11 +45,11 @@ from neutron import context
 from neutron.openstack.common import log as logging
 from neutron.openstack.common import loopingcall
 from neutron.plugins.common import constants as p_const
-from neutron.plugins.openvswitch.common import config  # noqa
 from neutron.plugins.openvswitch.common import constants
 
 
 LOG = logging.getLogger(__name__)
+cfg.CONF.import_group('AGENT', 'neutron.plugins.openvswitch.common.config')
 
 # A placeholder for dead vlans.
 DEAD_VLAN_TAG = str(q_const.MAX_VLAN_TAG + 1)
diff --git a/neutron/tests/unit/nuage/test_nuage_plugin.py b/neutron/tests/unit/nuage/test_nuage_plugin.py
index 424d7194f6..97a132f955 100644
--- a/neutron/tests/unit/nuage/test_nuage_plugin.py
+++ b/neutron/tests/unit/nuage/test_nuage_plugin.py
@@ -17,7 +17,6 @@ import contextlib
 import copy
 import os
 
-import contextlib
 import mock
 import netaddr
 from oslo.config import cfg
@@ -488,18 +487,6 @@ class TestNuageExtrarouteTestCase(NuagePluginV2TestCase,
                                        {'floatingip': {'port_id': None}})
                     self.assertIsNone(fip['floatingip']['router_id'])
 
-    def test_network_update_external_failure(self):
-        self._test_network_update_external_failure()
-
-    def test_floatingip_create_different_fixed_ip_same_port(self):
-        self._test_floatingip_create_different_fixed_ip_same_port()
-
-    def test_floatingip_update_different_router(self):
-        self._test_floatingip_update_different_router()
-
-    def test_floatingip_update_different_fixed_ip_same_port(self):
-        self._test_floatingip_update_different_fixed_ip_same_port()
-
 
 class NuageRouterTestExtensionManager(object):
 
diff --git a/neutron/tests/unit/test_db_plugin.py b/neutron/tests/unit/test_db_plugin.py
index 440e925c6f..8a4f3ec5ac 100644
--- a/neutron/tests/unit/test_db_plugin.py
+++ b/neutron/tests/unit/test_db_plugin.py
@@ -3456,7 +3456,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
             self.assertEqual(res.status_int,
                              webob.exc.HTTPClientError.code)
 
-    def test_update_subnet_ipv6_ra_mode_fails(self):
+    def test_update_subnet_ipv6_address_mode_fails(self):
         with self.subnet(ip_version=6, cidr='fe80::/64',
                          ipv6_address_mode=constants.IPV6_SLAAC) as subnet:
             data = {'subnet': {'ipv6_address_mode': constants.DHCPV6_STATEFUL}}
diff --git a/tox.ini b/tox.ini
index 0d3100e038..6e57c14ab0 100644
--- a/tox.ini
+++ b/tox.ini
@@ -65,7 +65,6 @@ commands = python setup.py build_sphinx
 # E128 continuation line under-indented for visual indent
 # E129 visually indented line with same indent as next logical line
 # E265 block comment should start with ‘# ‘
-# F811 redefinition of unused variable
 # F812 list comprehension redefines name from line
 # H237 module is removed in Python 3
 # H305 imports not grouped correctly
@@ -75,7 +74,7 @@ commands = python setup.py build_sphinx
 # H405 multi line docstring summary not separated with an empty line
 # H904 Wrap long lines in parentheses instead of a backslash
 # TODO(marun) H404 multi line docstring should start with a summary
-ignore = E125,E126,E128,E129,E265,F811,F812,H237,H305,H307,H401,H402,H404,H405,H904
+ignore = E125,E126,E128,E129,E265,F812,H237,H305,H307,H401,H402,H404,H405,H904
 show-source = true
 builtins = _
 exclude = .venv,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*egg,build,tools,.ropeproject,rally-scenarios