In the event of a failover, the survivable core server will only be able to deliver covered and diverted called parties to voice messaging systems that are connected to the same controlled system segment as the calling party.

A user of a voice mail system will only get a message waiting indication if their messaging server is in the same controlled segment as their station. The only way a voice mail user will be able to retrieve messages is through a dial connection or tool, such as Message Manager, to connect to the voice mail system.