Configure gw_iface for RAs only in Master HA Router

For an HA Router which does not have any IPv6 subnets in the external network
and when ipv6_gateway is not set, Neutron configures the gateway interface of
the router to receive Router Advts for default route. In an HA router, only
the Master instance has the IP addresses while the Backup instance does not
have any addresses (including LLA). In Kernel version 3.10, when the last
IPv6 address is removed from the interface, IPv6 proc entries corresponding
to the iface are also deleted. This is however reverted in the later versions
of kernel code.

This patch addresses this issue by configuring the proc entry only for the
Master HA Router instance instead of doing it un-conditionally.

Closes-Bug: #1494336
Change-Id: Ibf8e0ff64cda00314f8fa649ef5019c95c2d6004

diff --git a/neutron/agent/l3/ha.py b/neutron/agent/l3/ha.py
index 76363c9afba7ff092f79e04017596fa0f6584b6b..b66e1a37d2287ad502d6d6f29b4dab3c3e22946e 100644 (file)
--- a/neutron/agent/l3/ha.py
+++ b/neutron/agent/l3/ha.py
@@ -122,10 +122,23 @@ class AgentMixin(object):
                          'possibly deleted concurrently.'), router_id)
             return
 
+        self._configure_ipv6_ra_on_ext_gw_port_if_necessary(ri, state)
         self._update_metadata_proxy(ri, router_id, state)
         self._update_radvd_daemon(ri, state)
         self.state_change_notifier.queue_event((router_id, state))
 
+    def _configure_ipv6_ra_on_ext_gw_port_if_necessary(self, ri, state):
+        # If ipv6 is enabled on the platform, ipv6_gateway config flag is
+        # not set and external_network associated to the router does not
+        # include any IPv6 subnet, enable the gateway interface to accept
+        # Router Advts from upstream router for default route.
+        ex_gw_port_id = ri.ex_gw_port and ri.ex_gw_port['id']
+        if state == 'master' and ex_gw_port_id and ri.use_ipv6:
+            gateway_ips = ri._get_external_gw_ips(ri.ex_gw_port)
+            if not ri.is_v6_gateway_set(gateway_ips):
+                interface_name = ri.get_external_device_name(ex_gw_port_id)
+                ri.driver.configure_ipv6_ra(ri.ns_name, interface_name)
+
     def _update_metadata_proxy(self, ri, router_id, state):
         if state == 'master':
             LOG.debug('Spawning metadata proxy for router %s', router_id)

diff --git a/neutron/agent/l3/ha_router.py b/neutron/agent/l3/ha_router.py
index 33d750d300d8db6aabf8f705014aa43dda4ab27e..43e3447c7bdccb05e243569a8f582e1076313ad2 100644 (file)
--- a/neutron/agent/l3/ha_router.py
+++ b/neutron/agent/l3/ha_router.py
@@ -187,7 +187,7 @@ class HaRouter(router.RouterInfo):
 
     def _add_default_gw_virtual_route(self, ex_gw_port, interface_name):
         default_gw_rts = []
-        gateway_ips, enable_ra_on_gw = self._get_external_gw_ips(ex_gw_port)
+        gateway_ips = self._get_external_gw_ips(ex_gw_port)
         for gw_ip in gateway_ips:
                 # TODO(Carl) This is repeated everywhere.  A method would
                 # be nice.
@@ -197,9 +197,6 @@ class HaRouter(router.RouterInfo):
                     default_gw, gw_ip, interface_name))
         instance.virtual_routes.gateway_routes = default_gw_rts
 
-        if enable_ra_on_gw:
-            self.driver.configure_ipv6_ra(self.ns_name, interface_name)
-
     def _add_extra_subnet_onlink_routes(self, ex_gw_port, interface_name):
         extra_subnets = ex_gw_port.get('extra_subnets', [])
         instance = self._get_keepalived_instance()

diff --git a/neutron/agent/l3/router_info.py b/neutron/agent/l3/router_info.py
index 4c2db3655a4fdd58e89a98ff25b5f3d625850c5d..79f52bd5519950253cd25c28e42d3af084e4b72c 100644 (file)
--- a/neutron/agent/l3/router_info.py
+++ b/neutron/agent/l3/router_info.py
@@ -475,7 +475,6 @@ class RouterInfo(object):
 
     def _get_external_gw_ips(self, ex_gw_port):
         gateway_ips = []
-        enable_ra_on_gw = False
         if 'subnets' in ex_gw_port:
             gateway_ips = [subnet['gateway_ip']
                            for subnet in ex_gw_port['subnets']
@@ -485,11 +484,7 @@ class RouterInfo(object):
             if self.agent_conf.ipv6_gateway:
                 # ipv6_gateway configured, use address for default route.
                 gateway_ips.append(self.agent_conf.ipv6_gateway)
-            else:
-                # ipv6_gateway is also not configured.
-                # Use RA for default route.
-                enable_ra_on_gw = True
-        return gateway_ips, enable_ra_on_gw
+        return gateway_ips
 
     def _external_gateway_added(self, ex_gw_port, interface_name,
                                 ns_name, preserve_ips):
@@ -501,7 +496,12 @@ class RouterInfo(object):
         # will be added to the interface.
         ip_cidrs = common_utils.fixed_ip_cidrs(ex_gw_port['fixed_ips'])
 
-        gateway_ips, enable_ra_on_gw = self._get_external_gw_ips(ex_gw_port)
+        gateway_ips = self._get_external_gw_ips(ex_gw_port)
+        enable_ra_on_gw = False
+        if self.use_ipv6 and not self.is_v6_gateway_set(gateway_ips):
+            # There is no IPv6 gw_ip, use RouterAdvt for default route.
+            enable_ra_on_gw = True
+
         self.driver.init_router_port(
             interface_name,
             ip_cidrs,