Don't delete HA router primary VIP on agent restarts

An HA router's primary VIP was being deleted from the router
namespace when the L3 agent is restarted. Make sure that
doesn't happen and change the functional test to make sure
the bug stays squashed.

Change-Id: I0e5b416152bacf496de54bedee0fca8d3950be2b
Closes-Bug: #1432806
Closes-Bug: #1432785

neutron/agent/l3/ha.py

@@ -62,13 +62,13 @@ class AgentMixin(object):
             return
 
         ri._set_subnet_info(ha_port)
+        ri.ha_port = ha_port
+        ri._init_keepalived_manager(self.process_monitor)
         ri.ha_network_added(ha_port['network_id'],
                             ha_port['id'],
                             ha_port['ip_cidr'],
                             ha_port['mac_address'])
-        ri.ha_port = ha_port
 
-        ri._init_keepalived_manager(self.process_monitor)
         ri._add_keepalived_notifiers()
 
     def process_ha_router_removed(self, ri):

neutron/agent/l3/ha_router.py

@@ -131,6 +131,9 @@ class HaRouter(router.RouterInfo):
     def _get_keepalived_instance(self):
         return self.keepalived_manager.config.get_instance(self.ha_vr_id)
 
+    def _get_primary_vip(self):
+        return self._get_keepalived_instance().get_primary_vip()
+
     def get_ha_device_name(self, port_id):
         return (HA_DEV_PREFIX + port_id)[:self.driver.DEV_NAME_LEN]
 
@@ -141,7 +144,8 @@ class HaRouter(router.RouterInfo):
                          namespace=self.ns_name,
                          prefix=HA_DEV_PREFIX)
         self.driver.init_l3(interface_name, [internal_cidr],
-                            namespace=self.ns_name)
+                            namespace=self.ns_name,
+                            preserve_ips=[self._get_primary_vip()])
 
     def ha_network_removed(self):
         interface_name = self.get_ha_device_name(self.ha_port['id'])

neutron/agent/linux/keepalived.py

@@ -185,7 +185,7 @@ class KeepalivedInstance(object):
             ('        %s' % i for i in self.track_interfaces),
             ['    }'])
 
-    def _generate_primary_vip(self):
+    def get_primary_vip(self):
         """Return an address in the primary_vip_range CIDR, with the router's
         VRID in the host section.
 
@@ -197,7 +197,7 @@ class KeepalivedInstance(object):
 
         ip = (netaddr.IPNetwork(self.primary_vip_range).network +
               self.vrouter_id)
-        return netaddr.IPNetwork('%s/%s' % (ip, PRIMARY_VIP_RANGE_SIZE))
+        return str(netaddr.IPNetwork('%s/%s' % (ip, PRIMARY_VIP_RANGE_SIZE)))
 
     def _build_vips_config(self):
         # NOTE(amuller): The primary VIP must be consistent in order to avoid
@@ -212,8 +212,7 @@ class KeepalivedInstance(object):
         # interface IP and floating IPs) are placed in the
         # virtual_ipaddress_excluded section.
 
-        primary = KeepalivedVipAddress(str(self._generate_primary_vip()),
-                                       self.interface)
+        primary = KeepalivedVipAddress(self.get_primary_vip(), self.interface)
         vips_result = ['    virtual_ipaddress {',
                        '        %s' % primary.build_config(),
                        '    }']

neutron/tests/functional/agent/test_l3_agent.py

@@ -402,7 +402,8 @@ class L3AgentTestCase(L3AgentTestFramework):
         if enable_ha:
             port = router.get_ex_gw_port()
             interface_name = self.agent.get_external_device_name(port['id'])
-            self._assert_no_ip_addresses_on_interface(router, interface_name)
+            self._assert_no_ip_addresses_on_interface(router.ns_name,
+                                                      interface_name)
             utils.wait_until_true(lambda: router.ha_state == 'master')
 
             # Keepalived notifies of a state transition when it starts,
@@ -466,18 +467,28 @@ class L3AgentTestCase(L3AgentTestFramework):
             router.router[l3_constants.HA_INTERFACE_KEY],
             router.get_ha_device_name, router.ns_name))
 
-    def _assert_no_ip_addresses_on_interface(self, router, interface):
-        device = ip_lib.IPDevice(interface, namespace=router.ns_name)
-        self.assertEqual([], device.addr.list())
+    @classmethod
+    def _get_addresses_on_device(cls, namespace, interface):
+        return [address['cidr'] for address in
+                ip_lib.IPDevice(interface, namespace=namespace).addr.list()]
+
+    def _assert_no_ip_addresses_on_interface(self, namespace, interface):
+        self.assertEqual(
+            [], self._get_addresses_on_device(namespace, interface))
 
     def test_ha_router_conf_on_restarted_agent(self):
         router_info = self.generate_router_info(enable_ha=True)
-        router1 = self._create_router(self.agent, router_info)
+        router1 = self.manage_router(self.agent, router_info)
         self._add_fip(router1, '192.168.111.12')
         restarted_agent = neutron_l3_agent.L3NATAgentWithStateReport(
             self.agent.host, self.agent.conf)
         self._create_router(restarted_agent, router1.router)
         utils.wait_until_true(lambda: self.floating_ips_configured(router1))
+        self.assertIn(
+            router1._get_primary_vip(),
+            self._get_addresses_on_device(
+                router1.ns_name,
+                router1.get_ha_device_name(router1.ha_port['id'])))
 
 
 class L3HATestFramework(L3AgentTestFramework):

neutron/tests/unit/agent/linux/test_keepalived.py

@@ -200,11 +200,10 @@ class KeepalivedStateExceptionTestCase(base.BaseTestCase):
 
 class KeepalivedInstanceTestCase(base.BaseTestCase,
                                  KeepalivedConfBaseMixin):
-    def test_generate_primary_vip(self):
+    def test_get_primary_vip(self):
         instance = keepalived.KeepalivedInstance('MASTER', 'ha0', 42,
                                                  '169.254.192.0/18')
-        self.assertEqual('169.254.0.42/24',
-                         str(instance._generate_primary_vip()))
+        self.assertEqual('169.254.0.42/24', instance.get_primary_vip())
 
     def test_remove_adresses_by_interface(self):
         config = self._get_config()