Presently I have 4 sippers, 2 are working using OpenSer and 2 are not working using Kamailio. I have inherited these servers. There is an Asterisk server. When I run sip show peer SIP_SER against one of the servers that is not functioning for test calls, it states Status: UNREACHABLE. When I make test calls against it, I get Service Unavailable 503. The asterisk server shows "Unable to create channel of type 'SIP' (cause 20 - Subscriber absent).
At this point, I'm just looking for how to diagnose what is happening here. The OpenSer servers are connecting and successfully making test calls.
