Restart ovn-controller gracefully on PreStop

Otherwise, it will clean up chassis and other relevant records and cause
unnecessary router failovers.

Related-Issue: OSPRH-10821

pkg/ovncontroller/daemonset.go

@@ -75,7 +75,7 @@ func CreateOVNDaemonSet(
 			Lifecycle: &corev1.Lifecycle{
 				PreStop: &corev1.LifecycleHandler{
 					Exec: &corev1.ExecAction{
-						Command: []string{"/usr/share/ovn/scripts/ovn-ctl", "stop_controller"},
+						Command: []string{"/usr/local/bin/container-scripts/stop-ovn-controller.sh"},
 					},
 				},
 			},

templates/ovncontroller/bin/functions

@@ -27,6 +27,14 @@ ovs_dir=/var/lib/openvswitch
 FLOWS_RESTORE_SCRIPT=$ovs_dir/flows-script
 FLOWS_RESTORE_DIR=$ovs_dir/saved-flows
 SAFE_TO_STOP_OVSDB_SERVER_SEMAPHORE=$ovs_dir/is_safe_to_stop_ovsdb_server
+OVN_CONTROLLER_CLEANUP_CHASSIS_FLAG=$ovs_dir/cleanup_chassis
+
+function ovn_controller_is_restarting() {
+    if [ ! -f $OVN_CONTROLLER_CLEANUP_CHASSIS_FLAG ]; then
+        return 0
+    fi
+    return 1
+}
 
 function cleanup_ovsdb_server_semaphore() {
     rm -f $SAFE_TO_STOP_OVSDB_SERVER_SEMAPHORE 2>&1 > /dev/null

templates/ovncontroller/bin/stop-ovn-controller.sh

@@ -0,0 +1,25 @@
+#!/bin/sh
+#
+# Copyright 2024 Red Hat Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+set -ex
+source $(dirname $0)/functions
+
+OPTS=
+if ovn_controller_is_restarting; then
+    OPTS+="--restart"
+fi
+
+/usr/share/ovn/scripts/ovn-ctl stop_controller $OPTS