Cannot transfer calls over SIP trunk from ARC switchboard system

[carl_townshend]

Hi All

We have an issue, we can call over the SIP trunk from our CUCM to another Mitel system, this works fine, we can transfer calls etc using normal phones.

When try to transfer the call using our ARC switchboard over the SIP trunk it doesn't work, we did a packet capture and the switchboard is sending a CANCEL to the remote end.

Any ideas why this is?

Cheers

[TONY SMITH]

Guessing in the dark here without seeing your debugs.  But if I remember correctly the ARC CTI ports only support G711u, what codecs does the Mitel support?

[carl_townshend]

Hi, thanks for the response,

I did a packet capture and can see the below sdp info from the mitel, I do not see 711 in there, could this be the issue?

would this cause our side to cancel if they do not see a matching codec?

[TONY SMITH]

We'd need to actually see the packet capture, or SIP debugs, in order to comment properly.

That screenshot include G711u in the SDP, payload type 0 (PCMU/8000)

[carl_townshend]

Hi, I will get these uploaded, cheers

[carl_townshend]

Hi Tony, capture is attached

[TONY SMITH]

Cheers.  Which call are we looking at, can you let me know calling number, called number and time of call?   I can see a few calls which get as far as Ringing then are cancelled by the calling party.  What's a bit odd is that I can't see any SDP in any signalling from what I assume is CUCM 172.30.208.2,

[carl_townshend]

Hi

It will be the 24091993 to 88178530 call

cheers

[TONY SMITH]

There are several calls between those numbers.  In some the switchboard cancels while the call's ringing, in others the call connects and then the switchboard hangs up.  It's not really apparent from the SIP as to why this happens in either case.

You probably want to look at the CUCM traces for an example call.

Do calls direct from the switchboard work, for example if it's a consult transfer does the initial call fail or does it fail only when the call is transferred?

[Nithin Eluvathingal]

can you post the sip trunk configuration.. 

check if MTP enabled and MRG  selected  on  the device pool 

[carl_townshend]

Hi, If we enable MTP it breaks the trunk

[Nithin Eluvathingal]

If you enable MTP make sure that the device pool of  sip trunk has MRG applied.