feat: Confirm the OVN maintenance-worker periodic (ovn_maintenance_periodics) fires in our deployment PUC-2030

components/images-openstack.yaml

@@ -45,6 +45,7 @@ images:
     neutron_openvswitch_agent: "ghcr.io/rackerlabs/understack/neutron:2026.1"
     neutron_server: "ghcr.io/rackerlabs/understack/neutron:2026.1"
     neutron_rpc_server: "ghcr.io/rackerlabs/understack/neutron:2026.1"
+    neutron_ovn_maintenance_worker: "ghcr.io/rackerlabs/understack/neutron:2026.1"
     neutron_bagpipe_bgp: "ghcr.io/rackerlabs/understack/neutron:2026.1"
     neutron_netns_cleanup_cron: "ghcr.io/rackerlabs/understack/neutron:2026.1"
 

components/neutron/configmap-neutron-bin.yaml

@@ -1623,6 +1623,25 @@ data:
       kill -TERM 1
     }
 
+    $COMMAND
+  neutron-ovn-maintenance-worker.sh: |
+    #!/bin/bash
+
+    set -ex
+    COMMAND="${@:-start}"
+
+    function start () {
+      exec neutron-ovn-maintenance-worker \
+            --config-file /etc/neutron/neutron.conf \
+            --config-file /tmp/pod-shared/ovn.ini \
+            --config-file /etc/neutron/plugins/ml2/ml2_conf.ini \
+            --config-dir /etc/neutron/neutron.conf.d
+    }
+
+    function stop () {
+      kill -TERM 1
+    }
+
     $COMMAND
   neutron-server.sh: |
     #!/bin/bash

components/neutron/values.yaml

@@ -127,6 +127,9 @@ pod:
     neutron_server:
       - secret:
           name: neutron-ks-etc
+    neutron_ovn_maintenance_worker:
+      - secret:
+          name: neutron-ks-etc
 
   use_fqdn:
     neutron_agent: false
@@ -179,6 +182,9 @@ dependencies:
     rpc_server:
       jobs:
         - neutron-db-sync
+    ovn_maintenance_worker:
+      jobs:
+        - neutron-db-sync
     ironic_agent:
       jobs:
         - neutron-db-sync
@@ -204,6 +210,10 @@ manifests:
   daemonset_metadata_agent: false
   daemonset_ovs_agent: false
   deployment_rpc_server: false
+  deployment_ovn_maintenance_worker: true
+  # The janitor only needs the OVN maintenance worker. The chart enables the
+  # generic periodic worker by default; disable it.
+  deployment_periodic_worker: false
   daemonset_sriov_agent: false
   daemonset_l2gw_agent: false
   daemonset_bagpipe_bgp: false

python/neutron-understack/neutron_understack/l3_router/vrf.py

@@ -15,6 +15,7 @@
 
 from neutron_understack import config
 from neutron_understack import evpn_compat
+from neutron_understack import maintenance as understack_maintenance
 from neutron_understack.api.definitions import understack_vni as apidef
 from neutron_understack.l3_router import understack_vni_db
 
@@ -129,6 +130,12 @@ def get_plugin_type(cls):
     def get_plugin_description(self):
         return "Understack router VNI allocation plugin"
 
+    def ovn_maintenance_periodics(self, ovn_client):
+        LOG.warning("NETDEV ovn_maintenance_periodics called")
+        return [
+            understack_maintenance.NetdevRouterMaintenancePeriodics(self, ovn_client)
+        ]
+
     @staticmethod
     @resource_extend.extends([apidef.COLLECTION_NAME])
     def _extend_router_dict(router_res, router_db):

python/neutron-understack/neutron_understack/maintenance.py

@@ -0,0 +1,41 @@
+"""Periodics run in the OVN maintenance worker.
+
+Proves the mechanism fires end to end (hook discovered, worker runs, once
+cluster-wide) before the real reconciliation logic is added.
+"""
+
+# NOTE: Re-verify these symbols still exist on every neutron upgrade has_lock_periodic
+# and MAINTENANCE_NB_IDL_LOCK_NAME coz they are neutron-internal module.
+from neutron.plugins.ml2.drivers.ovn.mech_driver.ovsdb import maintenance
+from oslo_log import log as logging
+
+LOG = logging.getLogger(__name__)
+RECONCILE_SPACING = 600  # Temp
+
+
+class NetdevRouterMaintenancePeriodics:
+    """Reconcile netdev-router Ironic state from the OVN maintenance worker.
+
+    Body is a no-op log line.
+    """
+
+    def __init__(self, plugin, ovn_client):
+        self._plugin = plugin
+        # Take the maintenance lock so exactly one neutron-server runs these
+        # periodics.
+        LOG.warning(
+            "NETDEV periodic __init__; _nb_idl=%r",
+            getattr(ovn_client, "_nb_idl", "MISSING"),
+        )
+        self._idl = ovn_client._nb_idl.idl
+        self._idl.set_lock(maintenance.MAINTENANCE_NB_IDL_LOCK_NAME)
+
+    @property
+    def has_lock(self):
+        return self._idl.has_lock
+
+    @maintenance.has_lock_periodic(spacing=RECONCILE_SPACING, run_immediately=False)
+    def reconcile_netdev_routers(self):
+        # No-op: proves the periodic is scheduled and fires on exactly one
+        # neutron-server. host= lets us confirm it is not firing per-worker.
+        LOG.debug("netdev-router reconcile: placeholder, no action yet")