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fei he

Conference call issue

Hi All

We are hitting conference issue. When A call external B, call connected successful, then A conference external C.  A press conference button to dial C number, then B is be held. A connects to C successful. However, A press conference button again to bridge all 3 parts, both B and C are disconnected straight away.


I have went through logs, can see correct MTP has been allocated but no obvious error. Call flow as below:

7841---sip-- CUCM 9.1.2 ---- sip ---- CUBE-SP --- sip ----SP

A:  x56021

B: 0280621584

C: 0433181827

timestamp:  3:49:20 PM


Be aware, carrier is using 711a, 729a and 711u as preference in order. 


Any suggestion would highly appreciated..


Suresh Subramanian
Rising star

Hello Fei,


There is no information about the call in the attached file. Please collect the detailed ccm traces again and verify the calls are captured in those files. Together with CCM traces, please collect debug voice ccapi inout & debug ccsip message from CUBE.


few questions though


1) do you have hardware CFB configured and registered in CUCM?

2) If yes, have you added them to phone's MRGL?

3) If not, can you crosscheck if the phone's MRGL has software CFB associated?

4) If internal extension-A calls external number B and conference in with another INTERNAL extension C, does this scenario works?



Please rate all the helpful posts

//Suresh Please rate all the useful posts.

Hi Suresh

The call infor is indeed in attached sdl traces, timestamp is 15:49:20. All number has been formatted to +61.


At this stage, we only have software CFB, MTP configured and they all assigned to both phone and trunk MRGL.

In regards your question 4, same issue still occurs. 

BTW, the region between phone and trunk use 711.




Hello Fei,


Yes, I see the call but still incomplete.


02037852.001 |15:49:20.821 |AppInfo  |SIPTcp - wait_SdlSPISignal: Outgoing SIP TCP message to on port 5060 index 978
INVITE sip:+61280621584@ SIP/2.0
Via: SIP/2.0/TCP;branch=z9hG4bK54516c488ec5
From: <sip:+61881146021@>;tag=90269~26d4c3dc-c592-4bf1-9e7f-8a6916030c8b-53864634
To: <sip:+61280621584@>
Date: Thu, 12 Jun 2014 05:49:20 GMT
Call-ID: 4b0b3580-39913f60-53f3-4df130a@


I see invite, 100, 183 & 200 messages for the first call but no info for the 2nd call.


could you please collect the complete traces and the debugs i mentioned above from CUBE?



//Suresh Please rate all the useful posts.



couple of more things to verify

1) does the conference only between internal extensions work?

2) if not, check if the CFBs registered properly and reset them once and try again



//Suresh Please rate all the useful posts.

hi Suresh

We have not able to test conference call among all internal extensions as we only have 1 test phone at this stage. 

S/W CFBs are registered properly and reset does not make difference. 



Hi Suresh


2nd call should be started 15:49:35. 

Unfortunately, we cannot provide debug output as there is no onsite resource is able to perform further test at this stage.

The CUBE we are using is CUBE-SP which does not require any dial-peer configured.All call routing are configured under adjacency in SBC/SBE component. 




What is configured on dial-peers to CUCM?



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