automatic discovery of the network node trunk ID via OVN Gateway agent.

Previously, the network node trunk ID had to be manually configured in ml2 config. This had operational overhead and made the system less flexible when underling nodes used to deploy neutron is changed.

Author: syedhaseebahmed

python/neutron-understack/neutron_understack/config.py

@@ -50,13 +50,6 @@
             "is used to trunk all vlans used by a neutron router."
         ),
     ),
-    cfg.StrOpt(
-        "network_node_trunk_uuid",
-        help=(
-            "UUID of the trunk that is used to trunk all vlans used by a Neutron"
-            " router."
-        ),
-    ),
     cfg.StrOpt(
         "network_node_switchport_physnet",
         help=(

python/neutron-understack/neutron_understack/ironic.py

@@ -32,3 +32,17 @@ def _port_by_local_link(self, local_link_info: dict) -> BaremetalPort | None:
             )
         except StopIteration:
             return None
+
+    def baremetal_node_name(self, node_uuid: str) -> str | None:
+        try:
+            node = self.irclient.get_node(node_uuid)
+            return node.name if node else None
+        except Exception:
+            return None
+
+    def baremetal_node_uuid(self, node_name: str) -> str | None:
+        try:
+            node = self.irclient.get_node(node_name)
+            return node.id if node else None
+        except Exception:
+            return None

python/neutron-understack/neutron_understack/routers.py

@@ -98,9 +98,11 @@ def add_subport_to_trunk(shared_port: PortDict, segment: NetworkSegmentDict) ->
             },
         ]
     }
+    trunk_id = utils.fetch_network_node_trunk_id()
+
     utils.fetch_trunk_plugin().add_subports(
         context=n_context.get_admin_context(),
-        trunk_id=cfg.CONF.ml2_understack.network_node_trunk_uuid,
+        trunk_id=trunk_id,
         subports=subports,
     )
 
@@ -251,8 +253,7 @@ def handle_router_interface_removal(_resource, _event, trigger, payload) -> None
 
 def handle_subport_removal(port: Port) -> None:
     """Removes router's subport from a network node trunk."""
-    # trunk_id will be discovered dynamically at some point
-    trunk_id = cfg.CONF.ml2_understack.network_node_trunk_uuid
+    trunk_id = utils.fetch_network_node_trunk_id()
     LOG.debug("Router, Removing subport: %s(port)s", {"port": port})
     port_id = port["id"]
     try:

python/neutron-understack/neutron_understack/tests/test_routers.py

@@ -37,8 +37,8 @@ def test_when_successful(self, mocker):
         port = {"id": "port-123"}
         segment = {"segmentation_id": 42}
         mocker.patch(
-            "oslo_config.cfg.CONF.ml2_understack.network_node_trunk_uuid",
-            trunk_id,
+            "neutron_understack.utils.fetch_network_node_trunk_id",
+            return_value=trunk_id,
         )
         mocker.patch(
             "neutron_lib.context.get_admin_context", return_value="admin_context"
@@ -70,7 +70,8 @@ def test_when_successful(self, mocker):
 class TestHandleSubportRemoval:
     def test_when_successful(self, mocker, port_id, trunk_id):
         mocker.patch(
-            "oslo_config.cfg.CONF.ml2_understack.network_node_trunk_uuid", str(trunk_id)
+            "neutron_understack.utils.fetch_network_node_trunk_id",
+            return_value=str(trunk_id),
         )
         mock_remove = mocker.patch("neutron_understack.utils.remove_subport_from_trunk")
         port = {"id": str(port_id)}

python/neutron-understack/neutron_understack/tests/test_trunk.py

@@ -336,13 +336,13 @@ class TestCheckSubportsSegmentationId:
     def test_when_trunk_id_is_network_node_trunk_id(
         self,
         mocker,
-        oslo_config,
         understack_trunk_driver,
         trunk_id,
     ):
-        oslo_config.config(
-            network_node_trunk_uuid=str(trunk_id),
-            group="ml2_understack",
+        # Mock fetch_network_node_trunk_id to return the trunk_id
+        mocker.patch(
+            "neutron_understack.utils.fetch_network_node_trunk_id",
+            return_value=str(trunk_id),
         )
         # Mock to ensure the function returns early and doesn't call this
         allowed_ranges_mock = mocker.patch(
@@ -362,6 +362,11 @@ def test_when_segmentation_id_is_in_allowed_range(
         trunk_id,
         subport,
     ):
+        # Mock fetch_network_node_trunk_id to return a different trunk ID
+        mocker.patch(
+            "neutron_understack.utils.fetch_network_node_trunk_id",
+            return_value="different-trunk-id",
+        )
         allowed_ranges = mocker.patch(
             "neutron_understack.utils.allowed_tenant_vlan_id_ranges",
             return_value=[(1, 1500)],
@@ -380,6 +385,11 @@ def test_when_segmentation_id_is_not_in_allowed_range(
         trunk_id,
         subport,
     ):
+        # Mock fetch_network_node_trunk_id to return a different trunk ID
+        mocker.patch(
+            "neutron_understack.utils.fetch_network_node_trunk_id",
+            return_value="different-trunk-id",
+        )
         mocker.patch(
             "neutron_understack.utils.allowed_tenant_vlan_id_ranges",
             return_value=[(1, 1500)],