When should the failover Application Server be installed into the customer network in a Cisco Unified MeetingPlace solution?

When should the failover Application Server be installed into the customer network in a Cisco Unified MeetingPlace solution?

A.
After all configuration is completed on the primary Application Server

B.
Immediately after the Cisco Unified MeetingPlace internal Web Server is installed and configured

C.
After all configuration is completed on the Media Servers

D.
After all configuration is completed on every software component of the Cisco Unified MeetingPlace system as the very last step