diff --git a/neutron/agent/linux/dhcp.py b/neutron/agent/linux/dhcp.py
index 97e96fd81f0..ee855dc9acc 100644
--- a/neutron/agent/linux/dhcp.py
+++ b/neutron/agent/linux/dhcp.py
@@ -172,6 +172,7 @@ class DhcpBase(object):
         raise NotImplementedError()
 
 
+@six.add_metaclass(abc.ABCMeta)
 class DhcpLocalProcess(DhcpBase):
     PORTS = []
 
diff --git a/neutron/extensions/agent.py b/neutron/extensions/agent.py
index 13a8a39db94..bda48582952 100644
--- a/neutron/extensions/agent.py
+++ b/neutron/extensions/agent.py
@@ -17,6 +17,7 @@ import abc
 
 from neutron_lib.api import converters
 from neutron_lib import exceptions
+import six
 
 from neutron._i18n import _
 from neutron.api import extensions
@@ -122,6 +123,7 @@ class Agent(extensions.ExtensionDescriptor):
             return {}
 
 
+@six.add_metaclass(abc.ABCMeta)
 class AgentPluginBase(object):
     """REST API to operate the Agent.
 
diff --git a/neutron/extensions/dhcpagentscheduler.py b/neutron/extensions/dhcpagentscheduler.py
index 413387ea3c3..41f922e9f21 100644
--- a/neutron/extensions/dhcpagentscheduler.py
+++ b/neutron/extensions/dhcpagentscheduler.py
@@ -17,6 +17,7 @@ import abc
 
 from neutron_lib import constants
 from neutron_lib import exceptions
+import six
 
 from neutron._i18n import _
 from neutron.api import extensions
@@ -135,6 +136,7 @@ class NetworkNotHostedByDhcpAgent(exceptions.Conflict):
                 " by the DHCP agent %(agent_id)s.")
 
 
+@six.add_metaclass(abc.ABCMeta)
 class DhcpAgentSchedulerPluginBase(object):
     """REST API to operate the DHCP agent scheduler.
 
diff --git a/neutron/extensions/l3.py b/neutron/extensions/l3.py
index d82decc0af8..a47cab61e7b 100644
--- a/neutron/extensions/l3.py
+++ b/neutron/extensions/l3.py
@@ -18,6 +18,7 @@ import abc
 from neutron_lib.api import converters
 from neutron_lib import exceptions as nexception
 from oslo_config import cfg
+import six
 
 from neutron._i18n import _
 from neutron.api import extensions
@@ -220,6 +221,7 @@ class L3(extensions.ExtensionDescriptor):
             return {}
 
 
+@six.add_metaclass(abc.ABCMeta)
 class RouterPluginBase(object):
 
     @abc.abstractmethod
diff --git a/neutron/extensions/l3agentscheduler.py b/neutron/extensions/l3agentscheduler.py
index 33f5c31ad1c..f67ca0f51f7 100644
--- a/neutron/extensions/l3agentscheduler.py
+++ b/neutron/extensions/l3agentscheduler.py
@@ -18,6 +18,7 @@ import abc
 from neutron_lib import constants
 from neutron_lib import exceptions
 from oslo_log import log as logging
+import six
 import webob.exc
 
 from neutron._i18n import _, _LE
@@ -183,6 +184,7 @@ class DVRL3CannotRemoveFromDvrAgent(exceptions.Conflict):
                 "an agent in 'dvr' mode.")
 
 
+@six.add_metaclass(abc.ABCMeta)
 class L3AgentSchedulerPluginBase(object):
     """REST API to operate the l3 agent scheduler.
 
diff --git a/neutron/plugins/ml2/drivers/l2pop/rpc_manager/l2population_rpc.py b/neutron/plugins/ml2/drivers/l2pop/rpc_manager/l2population_rpc.py
index 09e53d60739..3273a1e785d 100644
--- a/neutron/plugins/ml2/drivers/l2pop/rpc_manager/l2population_rpc.py
+++ b/neutron/plugins/ml2/drivers/l2pop/rpc_manager/l2population_rpc.py
@@ -104,6 +104,7 @@ class L2populationRpcCallBackMixin(object):
         pass
 
 
+@six.add_metaclass(abc.ABCMeta)
 class L2populationRpcCallBackTunnelMixin(L2populationRpcCallBackMixin):
     '''Mixin class of L2-population call back for Tunnel.
 
diff --git a/neutron/plugins/ml2/drivers/type_tunnel.py b/neutron/plugins/ml2/drivers/type_tunnel.py
index 2f877e13729..d5804bbe10a 100644
--- a/neutron/plugins/ml2/drivers/type_tunnel.py
+++ b/neutron/plugins/ml2/drivers/type_tunnel.py
@@ -21,6 +21,7 @@ from oslo_config import cfg
 from oslo_db import api as oslo_db_api
 from oslo_db import exception as db_exc
 from oslo_log import log
+import six
 from six import moves
 from sqlalchemy import or_
 
@@ -45,6 +46,7 @@ def chunks(iterable, chunk_size):
         chunk = list(itertools.islice(iterator, 0, chunk_size))
 
 
+@six.add_metaclass(abc.ABCMeta)
 class TunnelTypeDriver(helpers.SegmentTypeDriver):
     """Define stable abstract interface for ML2 type drivers.
 
diff --git a/neutron/scheduler/base_resource_filter.py b/neutron/scheduler/base_resource_filter.py
index a2b1729123c..115b2be1e5f 100644
--- a/neutron/scheduler/base_resource_filter.py
+++ b/neutron/scheduler/base_resource_filter.py
@@ -15,7 +15,10 @@
 
 import abc
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class BaseResourceFilter(object):
     """Encapsulate logic that is specific to the resource type."""
     @abc.abstractmethod
diff --git a/neutron/scheduler/base_scheduler.py b/neutron/scheduler/base_scheduler.py
index 561d12e38c9..96be86f7fc7 100644
--- a/neutron/scheduler/base_scheduler.py
+++ b/neutron/scheduler/base_scheduler.py
@@ -17,7 +17,10 @@ import abc
 from operator import attrgetter
 import random
 
+import six
 
+
+@six.add_metaclass(abc.ABCMeta)
 class BaseScheduler(object):
     """The base scheduler (agnostic to resource type).
        Child classes of BaseScheduler must define the
diff --git a/neutron/tests/unit/extensions/foxinsocks.py b/neutron/tests/unit/extensions/foxinsocks.py
index d77dc764c95..1edde476790 100644
--- a/neutron/tests/unit/extensions/foxinsocks.py
+++ b/neutron/tests/unit/extensions/foxinsocks.py
@@ -16,6 +16,7 @@
 import abc
 
 from oslo_serialization import jsonutils
+import six
 
 from neutron.api import extensions
 from neutron import wsgi
@@ -27,6 +28,7 @@ class FoxInSocksController(wsgi.Controller):
         return "Try to say this Mr. Knox, sir..."
 
 
+@six.add_metaclass(abc.ABCMeta)
 class FoxInSocksPluginInterface(extensions.PluginInterface):
 
     @abc.abstractmethod