This article relates to Cisco TelePresence Video Communication Server Expressway.
Q. How does the VCS's clustering redundancy solution work with non-TANDBERG endpoints?
A. The VCS supports the H.225 Alternate Gatekeeper mechanism. When an endpoint registers to the VCS it is provided with a randomly ordered list of the IP addresses of the other VCS peers in the cluster. The random ordering ensures that non-TANDBERG endpoints that can only store a single alternate peer will failover evenly across the cluster.
Note that TANDBERG endpoints store all of the alternate IP addresses provided by the VCS and attempt to register with each of the alternates in turn.