Dropped calls

Unanswered Question
Nov 5th, 2008

Hi All, I have an odd problem I have a two users that are complaining of receiving calls and the call cuts off or they cannot here the person on the other end but, the other end can here them. This happens sporadically and on only two phones (7940's) out of about 60 IP phones. We are using CallManager 4.1, a friend of mine which has more experience than I mentioned that it could be asynchronous routing between this location and the gateway that hands off to our PRI. He reccommend trying to do a traceroute from each direction.

Has anyone had any similar issues to this and routing and traceroute would that help investing more time in that direction?



I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
a.gooding Wed, 11/05/2008 - 18:28

from my basic experience i think your friend is on the right track. anything special about your config that we should know about? normally, one way audio is caused by issues with routing. ive also seen calls dropping from gateways using MGCP if the timer isnt disabled.

the key is that its only happening on two phones...first off, are you sure its only happening on these two phones only? if so then we can narrow down to the two phones obviously.

secondly, if thats the case, have you checked the gateway settings on the phones itself.

third, are all these phones directly connected to the CCM or do you have any branches.

id say check the normal routing and what you can do is run a debug on the router to see whats going on. do it after hours though and test the two phones. you can do a debug voice ccapi inout and a debug vpm signal. im sure some of the guys would be able to shed a little more light on this once you give a little more info.

carbonscoring Mon, 11/10/2008 - 18:44

Hi ARVIND, thanks for the reply I've attached a crude drawing of WAN back to the phone thats having issus. There are two layer 3 links between a 6509 and 6513; wireless and fiber. This was the link that my co-worker thought about shutting down, one of them, and see if the issue goes away. Also what device would I run the debug commands on?

thanks for the help,


a.gooding Tue, 11/11/2008 - 04:59


run the debug on the PRI connected device and as well i think that if you do shut down the second link that should solve the issue or at least show what was is causing the issue. if you can pull one of the links (try the wireless) temporarily that would be great and do the test.

tell me how it goes.


This Discussion