diff --git a/networking_arista/ml2/rpc/arista_eapi.py b/networking_arista/ml2/rpc/arista_eapi.py
index f730d55d..6aa5d637 100644
--- a/networking_arista/ml2/rpc/arista_eapi.py
+++ b/networking_arista/ml2/rpc/arista_eapi.py
@@ -609,6 +609,10 @@ class AristaRPCWrapperEapi(AristaRPCWrapperBase):
                     port_name = 'name "%s"' % neutron_port['name']
 
                 device_owner = neutron_port['device_owner']
+
+                if port_id not in port_profiles:
+                    continue
+
                 vnic_type = port_profiles[port_id]['vnic_type']
                 network_id = neutron_port['network_id']
                 segments = []
diff --git a/networking_arista/ml2/rpc/arista_json.py b/networking_arista/ml2/rpc/arista_json.py
index ca789a44..b7b0ec18 100644
--- a/networking_arista/ml2/rpc/arista_json.py
+++ b/networking_arista/ml2/rpc/arista_json.py
@@ -78,8 +78,14 @@ class AristaRPCWrapperJSON(AristaRPCWrapperBase):
 
             resp = func(url, timeout=self.conn_timeout, verify=False,
                         data=data, headers=request_headers)
-            LOG.info(_LI('JSON response contains: %s'), resp.json())
-            return resp.json()
+            msg = (_LI('JSON response contains: %(code)s %(resp)s') %
+                   {'code': resp.status_code,
+                   'resp': resp.json()})
+            LOG.info(msg)
+            if resp.ok:
+                return resp.json()
+            else:
+                raise arista_exc.AristaRpcError(msg=resp.json().get('error'))
         except requests.exceptions.ConnectionError:
             msg = (_('Error connecting to %(url)s') % {'url': url})
             LOG.warning(msg)
@@ -149,8 +155,11 @@ class AristaRPCWrapperJSON(AristaRPCWrapperBase):
 
     def get_region_updated_time(self):
         path = 'agent/'
-        data = self._send_api_request(path, 'GET')
-        return {'regionTimestamp': data['uuid']}
+        try:
+            data = self._send_api_request(path, 'GET')
+            return {'regionTimestamp': data.get('uuid', '')}
+        except arista_exc.AristaRpcError:
+            return {'regionTimestamp': ''}
 
     def create_region(self, region):
         path = 'region/'
@@ -166,11 +175,14 @@ class AristaRPCWrapperJSON(AristaRPCWrapperBase):
         return self.delete_region(self.region)
 
     def get_region(self, name):
-        path = 'region/'
-        regions = self._send_api_request(path, 'GET')
-        for region in regions:
-            if region['name'] == name:
-                return region
+        path = 'region/%s' % name
+        try:
+            regions = self._send_api_request(path, 'GET')
+            for region in regions:
+                if region['name'] == name:
+                    return region
+        except arista_exc.AristaRpcError:
+            pass
         return None
 
     def sync_supported(self):
@@ -182,6 +194,13 @@ class AristaRPCWrapperJSON(AristaRPCWrapperBase):
     def sync_start(self):
         try:
             region = self.get_region(self.region)
+
+            # If the region doesn't exist, we may need to create
+            # it in order for POSTs to the sync endpoint to succeed
+            if not region:
+                self.register_with_eos()
+                return False
+
             if region and region['syncStatus'] == 'syncInProgress':
                 LOG.info('Sync in progress, not syncing')
                 return False
@@ -425,6 +444,10 @@ class AristaRPCWrapperJSON(AristaRPCWrapperBase):
                 instance = self._create_instance_data(inst_id, inst_host)
 
                 device_owner = neutron_port['device_owner']
+
+                if port_id not in port_profiles:
+                    continue
+
                 vnic_type = port_profiles[port_id]['vnic_type']
                 if device_owner == n_const.DEVICE_OWNER_DHCP:
                     instance_type = const.InstanceType.DHCP
diff --git a/networking_arista/tests/unit/ml2/rpc/test_arista_json_rpc_wrapper.py b/networking_arista/tests/unit/ml2/rpc/test_arista_json_rpc_wrapper.py
index 0423e400..82e43643 100644
--- a/networking_arista/tests/unit/ml2/rpc/test_arista_json_rpc_wrapper.py
+++ b/networking_arista/tests/unit/ml2/rpc/test_arista_json_rpc_wrapper.py
@@ -113,13 +113,28 @@ class TestAristaJSONRPCWrapper(testlib_api.SqlTestCase):
         ]
         self._verify_send_api_request_call(mock_send_api_req, calls)
 
+    @patch('requests.Response')
+    def test_sync_start_exception(self, mock_response):
+        mock_response.ok.return_value = False
+        self.assertFalse(self.drv.sync_start())
+
+    @patch(JSON_SEND_FUNC)
+    def test_sync_start_no_region(self, mock_send_api_req):
+        mock_send_api_req.return_value = {}
+        self.assertFalse(self.drv.sync_start())
+        calls = [
+            ('region/RegionOne', 'GET'),
+            ('region/', 'POST', [{'name': 'RegionOne'}])
+        ]
+        self._verify_send_api_request_call(mock_send_api_req, calls)
+
     @patch(JSON_SEND_FUNC)
     @patch(RAND_FUNC, _get_random_name)
     def test_sync_end(self, mock_send_api_req):
         mock_send_api_req.return_value = [{'requester':
                                            self._get_random_name()}]
         self.drv.current_sync_name = self._get_random_name()
-        assert self.drv.sync_end()
+        self.assertTrue(self.drv.sync_end())
         calls = [
             ('region/RegionOne/sync', 'DELETE')
         ]
@@ -131,12 +146,23 @@ class TestAristaJSONRPCWrapper(testlib_api.SqlTestCase):
         calls = [('region/', 'POST', [{'name': 'foo'}])]
         self._verify_send_api_request_call(mock_send_api_req, calls)
 
+    @patch('requests.Response')
+    def test_get_region_exception(self, mock_response):
+        mock_response.ok.return_value = False
+        self.assertIsNone(self.drv.get_region('foo'))
+
     @patch(JSON_SEND_FUNC)
     def test_delete_region(self, mock_send_api_req):
         self.drv.delete_region('foo')
         calls = [('region/', 'DELETE', [{'name': 'foo'}])]
         self._verify_send_api_request_call(mock_send_api_req, calls)
 
+    @patch('requests.Response')
+    def test_get_region__updated_exception(self, mock_response):
+        mock_response.ok.return_value = False
+        self.assertEqual(self.drv.get_region_updated_time(),
+                         {'regionTimestamp': ''})
+
     @patch(JSON_SEND_FUNC)
     def test_get_tenants(self, mock_send_api_req):
         self.drv.get_tenants()
diff --git a/networking_arista/tests/unit/ml2/test_arista_sync.py b/networking_arista/tests/unit/ml2/test_arista_sync.py
index 8d95a064..3cb49c10 100644
--- a/networking_arista/tests/unit/ml2/test_arista_sync.py
+++ b/networking_arista/tests/unit/ml2/test_arista_sync.py
@@ -111,6 +111,24 @@ class SyncServiceTest(testlib_api.SqlTestCase):
         db_lib.forget_network_segment(tenant_id, network_id)
         db_lib.forget_tenant(tenant_id)
 
+    def test_sync_start_failure(self):
+        """Tests that we force another sync when sync_start fails.
+
+           The failure could be because a region does not exist or
+           because another controller has the sync lock.
+        """
+        self.sync_service.synchronize = mock.MagicMock()
+        region_updated_time = {
+            'regionName': 'RegionOne',
+            'regionTimestamp': '424242'
+        }
+        self.rpc.get_region_updated_time.return_value = region_updated_time
+        self.rpc.check_cvx_availability.return_value = True
+        self.rpc.sync_start.return_value = False
+        self.sync_service.do_synchronize()
+        self.assertFalse(self.sync_service.synchronize.called)
+        self.assertTrue(self.sync_service._force_sync)
+
     def test_synchronize_not_required(self):
         """Tests whether synchronize() sends the right commands.