diff --git a/neutron/agent/dhcp/agent.py b/neutron/agent/dhcp/agent.py
index a5718409867..2ecc0705ed4 100644
--- a/neutron/agent/dhcp/agent.py
+++ b/neutron/agent/dhcp/agent.py
@@ -237,7 +237,7 @@ class DhcpAgent(manager.Manager):
                 # allocation failure. When the subnet is updated with a new
                 # allocation pool or a port is  deleted to free up an IP, this
                 # will automatically be retried on the notification
-                self.schedule_resync(e, network.id)
+                self.schedule_resync(str(e), network.id)
             if (isinstance(e, oslo_messaging.RemoteError) and
                     e.exc_type == 'NetworkNotFound' or
                     isinstance(e, exceptions.NetworkNotFound)):
@@ -362,7 +362,7 @@ class DhcpAgent(manager.Manager):
                         net = "*"
                     LOG.debug("resync (%(network)s): %(reason)s",
                               {"reason": r, "network": net})
-                self.sync_state(reasons.keys())
+                self.sync_state(list(reasons.keys()))
 
     def periodic_resync(self):
         """Spawn a thread to periodically resync the dhcp state."""
diff --git a/neutron/tests/unit/agent/dhcp/test_agent.py b/neutron/tests/unit/agent/dhcp/test_agent.py
index d56ca1579cf..6fa8b174955 100644
--- a/neutron/tests/unit/agent/dhcp/test_agent.py
+++ b/neutron/tests/unit/agent/dhcp/test_agent.py
@@ -672,7 +672,7 @@ class TestDhcpAgent(base.BaseTestCase):
             sync_state.side_effect = RuntimeError
             with testtools.ExpectedException(RuntimeError):
                 dhcp._periodic_resync_helper()
-            sync_state.assert_called_once_with(resync_reasons.keys())
+            sync_state.assert_called_once_with(list(resync_reasons.keys()))
             self.assertEqual(0, len(dhcp.needs_resync_reasons))
 
     def test_periodic_resync_helper_with_event(self):
@@ -680,7 +680,7 @@ class TestDhcpAgent(base.BaseTestCase):
             dhcp = dhcp_agent.DhcpAgent(HOSTNAME)
             dhcp.schedule_resync('reason1', 'a')
             dhcp.schedule_resync('reason1', 'b')
-            reasons = dhcp.needs_resync_reasons.keys()
+            reasons = list(dhcp.needs_resync_reasons.keys())
             with mock.patch.object(dhcp, 'sync_state') as sync_state:
                 sync_state.side_effect = RuntimeError
                 with testtools.ExpectedException(RuntimeError):