Merged next in

unit_tests/test_neutron_api_hooks.py

@@ -329,6 +329,22 @@ class NeutronAPIHooksTests(CharmTestCase):
             **_relation_data
         )
 
+    def test_neutron_plugin_api_relation_joined_w_mtu(self):
+        self.test_config.set('network-device-mtu', 1500)
+        _relation_data = {
+            'neutron-security-groups': False,
+            'l2-population': False,
+            'overlay-network-type': 'vxlan',
+            'network-device-mtu': 1500,
+        }
+        self.get_l2population.return_value = False
+        self.get_overlay_network_type.return_value = 'vxlan'
+        self._call_hook('neutron-plugin-api-relation-joined')
+        self.relation_set.assert_called_with(
+            relation_id=None,
+            **_relation_data
+        )
+
     def test_cluster_changed(self):
         self._call_hook('cluster-relation-changed')
         self.assertTrue(self.CONFIGS.write_all.called)