No MTP Resources Available

Unanswered Question
Dec 7th, 2007

After upgrading CallManager from 4.1 to 4.3 I started getting the No MTP Resources available error message when trying to place a caller on Hold or Transfer. This does not occur if the call is within the CallManager Cluster. It only occurs when a call is place to or originates from outside the Cluster. If I reset the MTP resources the Hold and Transfer functions will work temporarily.

I have this problem too.
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gogasca Sat, 12/08/2007 - 17:38


Did u select G729 as available codec for MOH under IPVMS service parameters?

MTP under ICT or H323 is checked?

Please clarify if MOH and supplementary services works fine.

When u say outside cluster it is for PSTN calls or for ICT calls?

Let us know


Ray Watkins Sat, 12/08/2007 - 19:19

Outside cluster....calls from PSTN or other non-callmanager phone systems in the organization. All of the regions are using G711. I will check the rest of your question Monday and let you know..


Ray Watkins Tue, 12/11/2007 - 08:04

MTP required is checked on the H323 gateway. This not a trunk. The route pattern points to this gateway to connect to the Avaya system and to the PSTN.

Ray Watkins Wed, 08/13/2008 - 12:36

Just to let everyone know. This was a caused by a duplex mismatch on the switch port.


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