SIP Calls over MPLS - Packet Sniffer Issue

[ciscovoipsupport]

Topology:

IP Phone => SCCP => CUCM => SIP => CUBE => Service provider

Issue:

I tried to collect packet trace from both port of CUBE to troubleshoot and identify choppy audio. Unfortunately the packets received and sent are over MPLS due to which i am not even able to see RTP Stream (not even SIP Streaming). Calls are sucessfull with G729 Codecs.

How can i decode and play G729 codec over MPLS network. My network team also use to say VRF. not sure if VRF network and MPLS network are the same.

Cisco Forum Document i reffered was https://supportforums.cisco.com/document/29616/utilizing-new-packet-capture-feature

It says we cannot use it for MPLS network. Are there any alternatives..

Please help..

[Suresh Subramanian · Accepted solution]

have you tried the steps given in the below link?

https://supportforums.cisco.com/docs/DOC-36782

[ciscovoipsupport]

Hi Suresh,

I had to stop at line 1 in that document as that command did not exists..

"create profile"
 

IOS is 15.2(4)M5

[Ayodeji Okanlawon · Accepted solution]

The create profile is not a command, its just telling to create the packet capture profile..

Here is a step by step guide

NB: you need to configure the packet capture before you start the call. Once the call ends, after transfer is completed, stop the capture
The int fa0/0 should be the interface that connects to ITSP..so change it to whatever interface that is.

1. Configure capture profile

               !
               ip traffic-export profile TAC mode capture
               bidirectional
               !

               interface fa0/0  ----> Interface which routes the traffic
               ip traffic-export apply TAC 99999999

2. Capture traffic with these exec (enable) level commands

Note: The exec cmds don’t appear until a profile has been configured

router#traffic-export interface fa0/0 clear
router#traffic-export interface fa0/0 start

router#traffic-export interface fa0/0 stop

3. Export the pcap file to a server

router#traffic-export interface fa0/0 copy ftp://x.x.x.x/capture.pcap