Caller does not hear a ringback

Unanswered Question

I have T1 connection between our Avaya System and Cisco Call Manager system using a Cisco 2801 mgcp gateway . When I make calls from the Avaya system phones to Cisco Call Manager phones everything works fine. The problem comes when I have a call come in through a PRI into to the Avaya system then routed over the T1 connection to the Call Manager system the caller does not get any ringback. The call goes through fine but the caller gets no ringback.

Call Manager Business Edition

System version:

Any ideas?



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Nicholas Matthews Mon, 06/22/2009 - 07:50
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Can you post 'debug isdn q931' for the bad call?


parshah Mon, 06/22/2009 - 09:12
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Is it a T1 CAS between Avaya and 2801 MGCP gateway or T1 CAS from PSTN?


9stucker Tue, 06/23/2009 - 05:41
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Give the following syntax a try.

voice rtp send-recv

Nicholas Matthews Tue, 06/23/2009 - 17:16
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T1 cas is tougher, but the actual command that may help here is:

voice call send-alert

You may also get different results from this command:

voice-card 0

no local-bypass



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