I have a three CCM cluster over WAN running 3.3.3 SR4a. It has been operational for almost four years. In the past two weeks there have been at least two instances where VoIP users could call out of the VoIP environment, receive calls from outside, but couldn't call the person in the desk next to them. Having not received any training on troubleshooting VoIP, where do I start looking? Any ideas as to what would prevent IP to IP calling in the HQ only. I can call other IP sets across the WAN, and I can call other IP sets in the HQ if I dial 9 and the complete number. Thanks in advance.
