documentation: several slight corrections to controller replacement procedure.

https://access.redhat.com/documentation/en/red-hat-openstack-platform/8/director-installation-and-usage/810-scaling-the-overcloud


1)

Step 6
Log in to each Controller node, remove the failed node from /etc/corosync/corosync.conf, and restart Corosync. For example, to remove the failed node from Controller node 0's configuration: 

Ends with: " Complete this on each node. "

Should be replaced with " Complete this on each controller node. "


2)
Step 7
 Start Pacemaker and Corosync on the new node
Should be replaced with:
 Start Pacemaker and Corosync on the new node from a remaining controller node.


3)
Step 8
 Enable and restart the keystone service through Pacemaker:

[heat-admin@overcloud-controller-3 ~]$ sudo pcs resource enable openstack-keystone-clone overcloud-controller-3

To add a note about disregarding the warnings maybe:
"Warning: 'openstack-keystone' is unmanaged                                                                     
Warning: 'openstack-keystone-clone' is unmanaged "