CUCM IM change postgres external database

If you need to change the postgres external database for CUCM, there a few steps to follow:

1. Change database server name
   a. External server setup -> External databases
2. Unassign servers and disable persistent chat
   a. Messaging -> Group Chat and Persistent Chat
   b. Change "Persistant Chat Database Assigntment" to unsassigned
   c. Uncheck "Enable Persistant Chat" and Save
3. Assign servers and enable persistent chat
   a. Messaging -> Group Chat and Persistent Chat
   b. Change "Persistant Chat Database Assigntment" to assigned
   c. Check "Enable Persistant Chat" and Save
4. Restart Cisco XCP Router
5. Start XCP Text Conference Manager

This blog post helped figure out the process:  http://collabtechnotes.blogspot.com/2015/07/postgre-sql-cisco-xcp-message-archiver.html