Inter-Cluster Communication
Inter-cluster communication is often required in very large, or widely distributed
installations, where more than one CallManager cluster is required to handle the
load. H.323 inter-cluster trunks are established to communicate between the different
clusters.
The latest release of Cisco CallManager can support up to eight servers
within a cluster, and all members of the cluster must reside on the same LAN.
However, even though an individual CallManager server can support up to 2,500
IP phones, there is a fixed limit of 10,000 IP phones per cluster. From these limitations,
it is obvious that several clusters would be required in very large local
networks, or any geographically dispersed network.
There are three types of implementations that might require multiple clusters
as well as inter-cluster communication: