<Include the documentation URL, the chapter or section number, and a detailed description of the issue.>

1. The Documentation URL:

https://access.redhat.com/documentation/en-us/red_hat_openstack_platform/17.1/html/installing_and_managing_red_hat_openstack_platform_with_director/assembly_replacing-controller-nodes#proc_removing-a-ceph-monitor-daemon_replacing-controller-nodes

1. Chapter:

20.3. Preparing the cluster for Controller node replacement

1. Section:

8. Remove the OVN southbound database server for the replaced Controller node from the cluster:

1. Obtain the server ID of the OVN southbound database server to be replaced:
   $ ssh tripleo-admin@<controller_ip> sudo podman exec ovn_cluster_north_db_server ovs-appctl -t /var/run/ovn/ovnnb_db.ctl cluster/status OVN_Southbound 2>/dev/null|grep -A4 Servers:

#Description:

Even though the Server ID of the OVN southbound database is to be obtained, information on the southbound database cannot be obtained because ovnnb_db.ctl in the ovn_cluster_north_db_server container is specified.　

To obtain information about the Southbound database, the following command must be executed.

```
$ ssh tripleo-admin@<controller_ip> sudo podman exec ovn_cluster_south_db_server ovs-appctl -t /var/run/ovn/ovnsb_db.ctl cluster/status OVN_Southbound 2>/dev/null|grep -A4 Servers:
```