[NSX-P/NSX-v3] Metadata route: make windows route optional

Introduce a new configuration option - windows_metadata_route.
Specifies whether an explicit route for metadata proxy access
on windows should be added.

The default value will be True for backward compatibility.
This option will need to be set to False for some guest OSes such
as RHEL8 as a duplicate metadata route can cause failures while
setting up networking.

Change-Id: If7507d0d4242cce2c73c7a2239149ec35fef232f

vmware_nsx/common/config.py

@@ -318,6 +318,10 @@ nsx_v3_and_p = [
                default="169.254.169.254/31",
                help=_("The metadata route used for native metadata proxy "
                       "service.")),
+    cfg.BoolOpt('windows_metadata_route',
+                default=True,
+                help=_("Inject a route for allowing windows guest access NSX "
+                       "native metadata proxy service")),
     cfg.StrOpt('dns_domain',
                default='openstacklocal',
                help=_("Domain to use for building the hostnames.")),

vmware_nsx/plugins/common_v3/availability_zones.py

@@ -60,6 +60,10 @@ class NsxV3AvailabilityZone(common_az.ConfiguredAvailabilityZone):
             native_metadata_route = az_info.get('native_metadata_route')
             if native_metadata_route:
                 self.native_metadata_route = native_metadata_route
+            windows_metadata_route = az_info.get('windows_metadata_route')
+            # Careful - this is a boolean
+            if windows_metadata_route is not None:
+                self.windows_metadata_route = windows_metadata_route
         else:
             self.metadata_proxy = None
             self.dhcp_profile = None

vmware_nsx/plugins/common_v3/plugin.py

@@ -2617,11 +2617,15 @@ class NsxPluginV3Base(agentschedulers_db.AZDhcpAgentSchedulerDbMixin,
                           subnet):
         # Always add option121.
         net_az = self.get_network_az_by_net_id(context, net_id)
-        options = {'option121': {'static_routes': [
+        static_routes = []
+        options = {'option121': {'static_routes': static_routes}}
+        if net_az.windows_metadata_route:
+            static_routes.append(
+                {'network': '%s' % net_az.native_metadata_route,
+                 'next_hop': '0.0.0.0'})
+        static_routes.append(
             {'network': '%s' % net_az.native_metadata_route,
-             'next_hop': '0.0.0.0'},
+             'next_hop': ip})
-            {'network': '%s' % net_az.native_metadata_route,
-             'next_hop': ip}]}}
         if subnet:
             sr, gateway_ip = self._build_static_routes(
                 subnet.get('gateway_ip'), subnet.get('cidr'),

vmware_nsx/plugins/nsx_p/availability_zones.py

@@ -40,6 +40,7 @@ class NsxPAvailabilityZone(v3_az.NsxV3AvailabilityZone):
         self.metadata_proxy = cfg.CONF.nsx_p.metadata_proxy
         self.dhcp_profile = cfg.CONF.nsx_p.dhcp_profile
         self.native_metadata_route = cfg.CONF.nsx_p.native_metadata_route
+        self.windows_metadata_route = cfg.CONF.nsx_p.windows_metadata_route
         self.default_overlay_tz = cfg.CONF.nsx_p.default_overlay_tz
         self.default_vlan_tz = cfg.CONF.nsx_p.default_vlan_tz
         self.default_tier0_router = cfg.CONF.nsx_p.default_tier0_router

vmware_nsx/plugins/nsx_v3/availability_zones.py

@@ -49,6 +49,7 @@ class NsxV3AvailabilityZone(v3_az.NsxV3AvailabilityZone):
         self.metadata_proxy = cfg.CONF.nsx_v3.metadata_proxy
         self.dhcp_profile = cfg.CONF.nsx_v3.dhcp_profile
         self.native_metadata_route = cfg.CONF.nsx_v3.native_metadata_route
+        self.windows_metadata_route = cfg.CONF.nsx_v3.windows_metadata_route
         self.dns_domain = cfg.CONF.nsx_v3.dns_domain
         self.nameservers = cfg.CONF.nsx_v3.nameservers
         self.default_overlay_tz = cfg.CONF.nsx_v3.default_overlay_tz