Resource Usage Within A Cluster; Example Deployment - Cisco TelePresence Administrator's Manual

Resource usage within a cluster

From software version X7, any traversal or non-traversal call licenses that have been installed on a cluster
peer are available for use by any peer in the cluster. (Prior to X7, licenses were not shared across the cluster;
each peer could only use the licenses that were loaded onto it.)
The number of licenses that can be installed on any one individual peer is limited to the maximum capacity of
each VCS unit, as follows:
500 non-traversal calls
n
100 traversal calls
n
2,500 registrations
n
Note that each VCS comes pre-installed with 2,500 registration licenses, and that registration licenses are
not shared across a cluster.
If a cluster peer becomes unavailable, the shareable licenses installed on that peer will remain available to
the rest of the cluster peers for two weeks from the time the cluster lost contact with the peer. This will
maintain the overall license capacity of the cluster — however, note that each peer is still limited by its
physical capacity as listed above. After this two week period, the licenses associated with the unavailable
peer are removed from the cluster. To maintain the same capacity for your cluster, you should ensure that
either the problem with the peer is resolved or new option keys are installed on another peer in the cluster.
Capacity alarms are raised if either of the following usage thresholds are reached:
the number of concurrent traversal/non-traversal calls reaches 90% of the capacity of the cluster
n
the number of concurrent traversal/non-traversal calls on any one unit reaches 90% of the physical
n
capacity of the unit

Example deployment

If, for example, you want to deploy a resilient cluster that can handle up to 750 concurrent non-traversal calls
and 250 concurrent traversal calls you could configure 4 peers as follows:
Non-traversal call licenses
Traversal call licenses
It would not matter to which peer an endpoint registers as the call licenses are shared across all of the peers.
If any one of the peers is temporarily taken out of service the full set of call licenses will remain available to
the entire cluster.
However, it is recommended that, where possible, the number of licenses is configured evenly across all
peers in the cluster.
Cisco VCS Administrator Guide (X7.1)
Peer Peer Peer Peer
1 2 3
250 250 250
100 100 50
Total cluster
4 capacity
0 750
0 250
Clustering and peers
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