Merge "Set trunk parent port as access port in ovs to avoid loop"

doc/source/contributor/internals/openvswitch_agent.rst

@@ -494,7 +494,7 @@ The IDs used for bridge and port names are truncated.
          |          tbr-trunk-id          |
          |                                |
          | tpt-parent-id   spt-subport-id |
-         |                   (tag 100)    |
+         |  (tag 0)          (tag 100)    |
          +-----+-----------------+--------+
                |                 |
                |                 |
@@ -514,27 +514,27 @@ spi-subport-id: int bridge side of the patch port that implements a subport.
 Trunk creation
 ++++++++++++++
 
-A VM is spawned passing to Nova the port-id of a parent port associated with
-a trunk. Neutron will pass to Nova the bridge where to plug the vif as part of the vif details.
-The os-vif driver creates the trunk bridge tbr-trunk-id if it does not exist in plug().
-It will create the tap interface tap1 and plug it into tbr-trunk-id setting the parent port ID in the external-ids.
-The OVS agent will be monitoring the creation of ports on the trunk bridges. When it detects
-that a new port has been created on the trunk bridge, it will do the following:
+A VM is spawned passing to Nova the port-id of a parent port associated
+with a trunk. Neutron will pass to Nova the bridge where to plug the
+vif as part of the vif details.  The os-vif driver creates the trunk
+bridge tbr-trunk-id if it does not exist in plug().  It will create the
+tap interface tap1 and plug it into tbr-trunk-id setting the parent port
+ID in the external-ids.  The trunk driver will wire the parent port via
+a patch port to connect the trunk bridge to the integration bridge:
 
 ::
 
- ovs-vsctl add-port tbr-trunk-id tpt-parent-id -- set Interface tpt-parent-id type=patch options:peer=tpi-parent-id
- ovs-vsctl add-port br-int tpi-parent-id tag=3 -- set Interface tpi-parent-id type=patch options:peer=tpt-parent-id
+ ovs-vsctl add-port tbr-trunk-id tpt-parent-id -- set Interface tpt-parent-id type=patch options:peer=tpi-parent-id -- set Port tpt-parent-id vlan_mode=access tag=0
+ ovs-vsctl add-port br-int tpi-parent-id -- set Interface tpi-parent-id type=patch options:peer=tpt-parent-id
 
 
-A patch port is created to connect the trunk bridge to the integration bridge.
-tpt-parent-id, the trunk bridge side of the patch is not associated to any
-tag. It will carry untagged traffic.
-tpi-parent-id, the br-int side the patch port is tagged with VLAN 3. We assume that the
-trunk is on network1 that on this host is associated with VLAN 3.
-The OVS agent will set the trunk ID in the external-ids of tpt-parent-id and tpi-parent-id.
-If the parent port is associated with one or more subports the agent will process them as
-described in the next paragraph.
+tpt-parent-id, the trunk bridge side of the patch will carry untagged
+traffic (vlan_mode=access tag=0).  The OVS agent will be monitoring the
+creation of ports on the integration bridge.  tpi-parent-id, the br-int
+side the patch port is tagged with VLAN 3 by ovs-agent.  We assume that
+the trunk is on network1 that on this host is associated with VLAN 3.
+If the parent port is associated with one or more subports the agent
+will process them as described in the next paragraph.
 
 Subport creation
 ++++++++++++++++

neutron/services/trunk/drivers/openvswitch/agent/trunk_manager.py

@@ -91,7 +91,7 @@ class TrunkParentPort(object):
             self.DEV_PREFIX, port_id)
         self._transaction = None
 
-    def plug(self, br_int):
+    def plug(self, br_int, tag=0):
         """Plug patch ports between trunk bridge and given bridge.
 
         The method plugs one patch port on the given bridge side using
@@ -124,6 +124,9 @@ class TrunkParentPort(object):
                                    self.patch_port_trunk_name))
             txn.add(ovsdb.db_set('Interface', self.patch_port_trunk_name,
                                  *patch_trunk_attrs))
+            txn.add(ovsdb.db_set('Port', self.patch_port_trunk_name,
+                                 ('vlan_mode', 'access'),
+                                 ('tag', tag)))
 
     def unplug(self, bridge):
         """Unplug the trunk from bridge.
@@ -167,12 +170,7 @@ class SubPort(TrunkParentPort):
         :param br_int: an integration bridge where peer endpoint of patch port
                        will be created.
         """
-        ovsdb = self.bridge.ovsdb
-        with ovsdb.transaction() as txn:
-            super(SubPort, self).plug(br_int)
-            txn.add(ovsdb.db_set(
-                "Port", self.patch_port_trunk_name,
-                ("tag", self.segmentation_id)))
+        super(SubPort, self).plug(br_int, tag=self.segmentation_id)
 
     def unplug(self, bridge):
         """Unplug the sub port from the bridge.

neutron/tests/functional/services/trunk/drivers/openvswitch/agent/test_trunk_manager.py

@@ -54,6 +54,14 @@ class TrunkParentPortTestCase(base.BaseSudoTestCase):
                       self.trunk.bridge.get_port_name_list())
         self.assertIn(self.trunk.patch_port_int_name,
                       self.br_int.get_port_name_list())
+        self.assertEqual(
+            'access',
+            self.trunk.bridge.db_get_val(
+                'Port', self.trunk.patch_port_trunk_name, 'vlan_mode'))
+        self.assertEqual(
+            0,
+            self.trunk.bridge.db_get_val(
+                'Port', self.trunk.patch_port_trunk_name, 'tag'))
 
     def test_plug_failure_doesnt_create_ports(self):
         with mock.patch.object(

releasenotes/notes/bug-2048785-trunk-parent-vlan-mode-9280ff2d45403bde.yaml

@@ -0,0 +1,8 @@
+---
+issues:
+  - |
+    The fix of `bug 2048785 <https://bugs.launchpad.net/neutron/+bug/2048785>`_
+    only fixes newly created trunk parent ports. If the fix of already existing
+    trunks is needed, then either delete and re-create the affected trunks
+    or set tpt ports' vlan_mode and tag manually:
+    ``ovs-vsctl set Port tpt-... vlan_mode=access tag=0``