Treat MLAG pairs as a single physical network

With this change HPB is compatible with MLAG pairs by listing
them as peer1_peer2 in the physical network's name.

Change-Id: Idd86162b9d315c174c583f41be98b4e1a163eff5

networking_arista/ml2/arista_ml2.py

@@ -27,6 +27,9 @@ from oslo_utils import excutils
 import requests
 from six import add_metaclass
 
+from neutron.db import api as db_api
+from neutron.db.models.plugins.ml2 import vlanallocation
+
 from networking_arista._i18n import _, _LI, _LW, _LE
 from networking_arista.common import db_lib
 from networking_arista.common import exceptions as arista_exc
@@ -84,6 +87,21 @@ class AristaRPCWrapperBase(object):
         self.security_group_driver = arista_sec_gp.AristaSecGroupSwitchDriver(
             self._ndb)
 
+        # We denote mlag_pair physnets as peer1_peer2 in the physnet name, the
+        # following builds a mapping of peer name to physnet name for use
+        # during port binding
+        self.mlag_pairs = {}
+        session = db_api.get_reader_session()
+        with session.begin():
+            physnets = session.query(
+                vlanallocation.VlanAllocation.physical_network
+            ).distinct().all()
+        for (physnet,) in physnets:
+            if '_' in physnet:
+                peers = physnet.split('_')
+                self.mlag_pairs[peers[0]] = physnet
+                self.mlag_pairs[peers[1]] = physnet
+
         # Indication of CVX availabililty in the driver.
         self._cvx_available = True
 
@@ -1989,6 +2007,10 @@ class AristaRPCWrapperEapi(AristaRPCWrapperBase):
             if hostname:
                 switch_id = response[1]['hosts'][hostname]['name']
 
+            # Check if the switch is part of an MLAG pair, and lookup the
+            # pair's physnet name if so
+            physnet = self.mlag_pairs.get(physnet, physnet)
+
             for k in response[1]['hosts']:
                 mac_to_hostname[response[1]['hosts'][k]['name']] = k
 

networking_arista/ml2/mechanism_arista.py

@@ -273,7 +273,8 @@ class AristaDriver(driver_api.MechanismDriver):
         mac_to_hostname = physnet_info.get('mac_to_hostname', {})
         for link in link_info:
             if link.get('switch_id') in mac_to_hostname:
-                return mac_to_hostname.get(link.get('switch_id'))
+                physnet = mac_to_hostname.get(link.get('switch_id'))
+                return self.rpc.mlag_pairs.get(physnet, physnet)
 
     def _bind_port_to_baremetal(self, context, segment, physnet_info):
 

networking_arista/tests/unit/ml2/test_arista_mechanism_driver.py

@@ -1559,7 +1559,7 @@ class AristaRPCWrapperInvalidConfigTestCase(base.BaseTestCase):
                           arista_ml2.AristaRPCWrapperEapi, ndb)
 
 
-class NegativeRPCWrapperTestCase(base.BaseTestCase):
+class NegativeRPCWrapperTestCase(testlib_api.SqlTestCase):
     """Negative test cases to test the RPC between Arista Driver and EOS."""
 
     def setUp(self):

networking_arista/tests/unit/ml2/test_arista_type_driver.py

@@ -21,7 +21,6 @@ from oslo_config import cfg
 
 from neutron.db import api as db_api
 from neutron.db.models.plugins.ml2 import vlanallocation
-from neutron.tests import base
 from neutron.tests.unit import testlib_api
 
 from networking_arista.ml2.drivers.driver_helpers import VlanSyncService
@@ -33,7 +32,7 @@ EAPI_SEND_FUNC = ('networking_arista.ml2.arista_ml2.AristaRPCWrapperEapi'
                   '._send_eapi_req')
 
 
-class AristaTypeDriverTest(base.BaseTestCase):
+class AristaTypeDriverTest(testlib_api.SqlTestCase):
 
     def setUp(self):
         super(AristaTypeDriverTest, self).setUp()