We have a Nortel PBX connected to an Adtran 916. We are experiencing intermittent call drops of incoming calls. Callers report that they call our main number, the call is answered in 2 rings (as programmed), there is a couple seconds of silence and then they here a dial tone. This can be replicated when calling from an inside line to our main number. What should happen after 2 rings is that the caller hears our auto attendant.
When viewing the call monitor in the GUI, I can see the calls coming in and terminating. During one call "no battery" showed next to both lines under status.
Thanks for posting to our forum. Is the connection from the ADTRAN to the CPE analog FXS or PRI? You can run a debug to determine where the call is failing but you will have to do it from the CLI. The trick is to be able to catch the call, as intermittent problems are difficult to pin down. If you can log into the ADTRAN, run these commands:
debug sip stack message
debug voice verbose
debug isdn l2-for
debug int fxs
These debugs would catch the SIP call leg, the internal call routing in the ADTRAN, and the TDM side of the call. If you are able to catch a call, we can help you look through the debug. If you need to run a persistent debug, this may help - Enabling Persistent Debug Logging