I have a small customer with CUCM 8.5 Pub and Sub. Pub is located in the DC and all the phones/gateways are registered with Sub at the office. I am using PCD simple migration process so no IP address change.
PCD simple migration is a three step process:
1) Export the data from Pub and Sub
2) Shutdown the production Pub and install/import configuration into new Pub 10.5.
3) Shutdown the production Sub and install/import configuration into new Sub 10.5.
My question is if I put a "pause" after step 2 it should not caused any outage up until that point right because all phones and gateways are registered with Sub onsite?