Inter sites calls ring and get connected allright but no voice

[bassono_t]

Hi All,

Am experiencing a problem with my telephony network consisting of satellites site with CCME and a central site with CCM 4.1. Intra sites calls go fine, but inter-sites calls ring, get connected when picked up but no voice can be heard.

This is happening without any change being carried out in the newtork.

Any Idea where the problem may be lying?

Thanks for helping.

Rgds,

[Dennis Mink · Accepted solution]

I would check routing and possible ACL's first.

Simplest thing to test is to ping from on local voice vlan IP address to a remote IP address in a Voice VLAN. this does not neccessarily test ACL's but it does test end to end connectivity between phone. Remember that a phone ringing is just signalling and the play back of a wav file from CUCM or CME.

Would also be worth setting up like wireshark to see if your RTP hits the end point, use IP communicator for this matter, so you wont have to muck around with SPAN ports.

Try this first and let us know how you go, before we check other things like going into trace files

[Udit Mehrotra]

What would be the codec for calls between sites?

Remember if you are doing any other coded except g711ulaw between sites you will need a transcoder as CUE can only do G711ulaw.

Also check supplementary-services settings for call transfer are set up correctly for call forward and transfer.

The root cause can be anything as of now. I would start troublehooting by checking if IP connectivity is up and the UDP ports for RTP are open. Since calls to extensions work fine and the problem is with voicemail, this might be set up correctly. Next collect following debugs to see the state machine of the IOS when the call is being sent to VM:

debug h225 asn1

debug h245 asn1

debug voip ccapi default

debug ccsip messages

debug ccsip media

Along with the above debugs, please attach running config of CME to compare the state machine with configuration.

[bassono_t]

Hi all

Thank you all for the replies. As Dennis said it was indeed a routing problem because for no obvious reason, networks that are statically configured with a /16 mask were showing up in the routing table with a /24 mask. I couldn't get a clue of the source of the problem until solving the problem by copying a backup config to startup and reloading.

Rgds,