We currently have one callmanager 4.3 and would like add another for redundancy. Can you tell me what software licensing i will need to do this? Do I need to buy the same licensing as we own for the original? Can we use the first callmanagers license since this one will be passive unless the first one breaks.
You will need to purchase a Callmanager server license for each server in your cluster. Adding an additional Callmanager creates a Callmanager cluster and creates a publisher/subscriber relationship between the 2 servers. In this scenario, even though you register all phones to one server, both servers are active and capable of call processing, MOH, TFTP, etc. The only way you could use a single license is if you only plan to boot up the second server in case of a failure and at that time use a backup to restore the configuration. This obviously does not provide much redundancy or real-time failover.
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