Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

ICT trunk troubleshooting guide


Anyone has recommendation of ICT trunk troubleshooting guide for CCM ?

Presently, I have a weird issue when a cluster calling to another cluster the distant cluster will heard 'breaking up' voice audio issue, which cannot heard properly

Have trace the satistics on the phone there are heavily packet loss in the distant end.

Any MPLS commands to check if the WAN link id flapping ? So I can guide my NOC team to assist ?



ICT trunk troubleshooting guide

If the problem relates to voice breaking up, it relates only to the media path of the call, not the signaling.

You should focus your efforts on the RTP path and not on the protocol used on the ICT trunk.

You can get the statistics for the Remote IP, port and packet loss from the phone webpage. As well a packet capture from the back of the Phone with Wireshark will reveal a lot of statistics relating to Voice Quality

Then you should try to identify the traffic flow across your network, using show ip cef exact-route. or other routing verification.

Make sure your Switches and Routers are respecting the packet markings, and you can see the traffic been matched by your policy maps. Check links for congestions, dropped packets, buffers full.

About MPLS I would recommend to check the DSCP to EXP bits mapping, to make sure traffic gets treated across your provider.

If you can confirm a delivery of steady RTP with 50 packets per second, and little jitter and good QoS marking to the PE edge, and the other CE router you get higher than normal jitter and packet loss, you can blame the provider for not meeting their SLA.

As well you might consider using the new traffic export feature on the ISR to get a packet capture on the IOS itself, for your analysis.

It's mostly network and QoS troubleshoot what you are looking at.

Hope this helps.

New Member

ICT trunk troubleshooting guide

Thanks Robert for the guide... If using CCM SDL and SDI trace calls, does that help with any information ?

Hall of Fame Super Silver

ICT trunk troubleshooting guide

If the call connects fine traces are not going to reveal anything wrong, you need to troubleshoot the network connection between the endpoints, do you have QoS in place?  Make sure your RTP traffic is marked properly, prioritized and honored end to end on the network.



New Member

ICT trunk troubleshooting guide

Minimum you can do is enable the Quality Reporting tools. This with CMR may give you some additional insight but that will get you back to QOS like Chris was saying, it the CMR show jitter and packet loss that will be QOS.