[gnuoy,r=james-page] add l2population support, on by default.

config.yaml

@@ -102,4 +102,10 @@ options:
       .
       This network will be used for tenant network traffic in overlay
       networks.
-
+  l2-population:
+    type: boolean
+    default: True
+    description: |
+      Populate the forwarding tables of virtual switches (LinuxBridge or OVS),
+      to decrease broadcast traffics inside the physical networks fabric while
+      using overlays networks (VXLan, GRE).

hooks/quantum_contexts.py

@@ -190,7 +190,8 @@ class QuantumGatewayContext(OSContextGenerator):
             'plugin': config('plugin'),
             'debug': config('debug'),
             'verbose': config('verbose'),
-            'instance_mtu': config('instance-mtu')
+            'instance_mtu': config('instance-mtu'),
+            'l2_population': config('l2-population'),
         }
         return ctxt
 

templates/icehouse/ml2_conf.ini

@@ -5,7 +5,7 @@
 [ml2]
 type_drivers = gre,vxlan
 tenant_network_types = gre,vxlan
-mechanism_drivers = openvswitch
+mechanism_drivers = openvswitch,l2population
 [ml2_type_gre]
 tunnel_id_ranges = 1:1000
 [ml2_type_vxlan]
@@ -15,5 +15,6 @@ enable_tunneling = True
 local_ip = {{ local_ip }}
 [agent]
 tunnel_types = gre
+l2_population = {{ l2_population }}
 [securitygroup]
 firewall_driver = neutron.agent.linux.iptables_firewall.OVSHybridIptablesFirewallDriver

unit_tests/test_quantum_contexts.py

@@ -231,7 +231,8 @@ class TestQuantumGatewayContext(CharmTestCase):
                            "OVSQuantumPluginV2",
             'plugin': 'ovs',
             'debug': False,
-            'verbose': True
+            'verbose': True,
+            'l2_population': True,
         })