About Clusters - Cisco TelePresence Administrator's Manual

About clusters

A VCS can be part of a cluster of up to six VCSs. Each VCS in the cluster is a peer of every other VCS in the
cluster. When creating a cluster, you define a cluster name and nominate one peer as the master from which
all relevant configuration is replicated to the other peers in the cluster. Clusters are used to:
increase the capacity of your VCS deployment compared with a single VCS
n
provide redundancy in the rare case that a VCS becomes inaccessible (for example, due to a network or
n
power outage) or while it is in maintenance mode (for example, during a software upgrade)
Peers share information with each other about their use of bandwidth, registrations, and user accounts. This
allows the cluster to act as one large VCS Local Zone as shown in the example below.
About the configuration master
All peers in a cluster must have identical configuration for subzones, zones, links, pipes, authentication,
bandwidth control and Call Policy. To achieve this, you define a cluster name and nominate one peer as the
configuration master. Any configuration changes made to the master peer are then automatically replicated
across all the other peers in the cluster.
You should only make configuration changes on the master VCS. Any changes made on other peers are not
reflected across the cluster, and will be overwritten the next time the master's configuration is replicated
across the peers. The only exceptions to this are:
Cisco VCS Administrator Guide (X7.2)
Clustering and peers
Page 149 of 498