- Bronze, 100 points or more
We're running a CUCM 8.6 cluster and we've configured about 150 users with Extension Mobility. As part of the server configuration, you need to configure URLs in System > Enterprise Parameters and a URL for the EM service itself. We currently have these configured with an IP address to avoid a system dependency on DNS (per best practices on deployment), however, this presents a challenge when operating during a cluster node failover.
As is, the enterprise paramter URLs and the EM service URL are pointed at the CUCM Subscriber. If the subscriber fails, this means that all IP Phone service URLs and Extension Mobility will be inoperable.
We're looking for a recommendation on mitigating this single point of failure, as we need Extension Mobility to be fully HA in the environment. Should we bite the bullet and configure these URL's with a DNS-dependent hostname with a short TTL (so we can change the IP in an emergency), or is there a better solution here? It's my understanding that Enterprise Parameters are cluster-wide, so even if we were to install a second instance of the Extension Mobility service on the IP phones with a URL to the other cluster node, we'd also have to configure multiple softkeys to them in order to avoid the dependency on the Services button.