Delete gateway conntrack state when remove external gateway

This fixed the problem that a gateway ip conntrack state not cleared
when user clears a router external gateway.

Change-Id: I77f22d9504430259b01366e6296a99ba1cd6a046
Closes-Bug: #1488730

neutron/agent/l3/ha_router.py

@@ -362,10 +362,10 @@ class HaRouter(router.RouterInfo):
                                                        interface_name)
 
     def delete(self, agent):
+        super(HaRouter, self).delete(agent)
         self.destroy_state_change_monitor(self.process_monitor)
         self.ha_network_removed()
         self.disable_keepalived()
-        super(HaRouter, self).delete(agent)
 
     def process(self, agent):
         super(HaRouter, self).process(agent)

neutron/agent/l3/router_info.py

@@ -202,6 +202,9 @@ class RouterInfo(object):
     def remove_floating_ip(self, device, ip_cidr):
         device.delete_addr_and_conntrack_state(ip_cidr)
 
+    def remove_external_gateway_ip(self, device, ip_cidr):
+        device.delete_addr_and_conntrack_state(ip_cidr)
+
     def get_router_cidrs(self, device):
         return set([addr['cidr'] for addr in device.addr.list()])
 
@@ -538,6 +541,12 @@ class RouterInfo(object):
     def external_gateway_removed(self, ex_gw_port, interface_name):
         LOG.debug("External gateway removed: port(%s), interface(%s)",
                   ex_gw_port, interface_name)
+        device = ip_lib.IPDevice(interface_name, namespace=self.ns_name)
+        for ip_addr in ex_gw_port['fixed_ips']:
+            self.remove_external_gateway_ip(device,
+                                            common_utils.ip_to_cidr(
+                                                ip_addr['ip_address'],
+                                                ip_addr['prefixlen']))
         self.driver.unplug(interface_name,
                            bridge=self.agent_conf.external_network_bridge,
                            namespace=self.ns_name,

neutron/agent/linux/ip_lib.py

@@ -231,9 +231,10 @@ class IPDevice(SubProcessBase):
 
         This terminates any active connections through an IP.
 
-        cidr: the IP address for which state should be removed.  This can be
-            passed as a string with or without /NN.  A netaddr.IPAddress or
-            netaddr.Network representing the IP address can also be passed.
+        :param cidr: the IP address for which state should be removed.
+            This can be passed as a string with or without /NN.
+            A netaddr.IPAddress or netaddr.Network representing the IP address
+            can also be passed.
         """
         self.addr.delete(cidr)
 

neutron/tests/unit/agent/l3/test_legacy_router.py

@@ -48,6 +48,15 @@ class TestBasicRouterOperations(BasicRouterTestCaseFramework):
 
         device.delete_addr_and_conntrack_state.assert_called_once_with(cidr)
 
+    def test_remove_external_gateway_ip(self):
+        ri = self._create_router(mock.MagicMock())
+        device = mock.Mock()
+        cidr = '172.16.0.0/24'
+
+        ri.remove_external_gateway_ip(device, cidr)
+
+        device.delete_addr_and_conntrack_state.assert_called_once_with(cidr)
+
 
 @mock.patch.object(ip_lib, 'send_ip_addr_adv_notif')
 class TestAddFloatingIpWithMockGarp(BasicRouterTestCaseFramework):