I have a customer with 7815 and i need to give him some redundancy by getting him anther CCM, i am wondering if we can sell him 7825 and join the same cluster.
technically i guess it is feasible but i am wondering if someone has any comments.
You can do this no problem. The hardware does not have to be the same for all servers in the cluster.
However, I would be cautious about how many devices you intend to support on the 7815. Make sure you go through the CallManager Capacity Tool:
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