CallManager 4.1(3)sr4d "Duplex Streaming Enabled"

Unanswered Question
Oct 8th, 2007
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Hi Guys,

Has anyone seen the following issue?

I have 7941's and 61's with SCCP41.8-3-1S load.

We had an MOH and Annunciator issue through a firewall. It was suggested to try the Duplex Streaming Enabled CallManager service parameter.

By default it is set to False, we set it to true and tested.

Now if I call from phone a to phone b and press hold on phone a. Phone b will start to play the music on hold.

Phone B also now has no contact with callmanager. It is unresponsive, it wont end the call, transfer etc.

It is easily reproducible in different environments. i.e. doesnt look like network, looks more like phone load / behaviour.

We did an ethereal trace and you can see the phone send a Skinny Alarm to the callmanager in response to a StartMediaTransmission message.

Anyway, just thought I would ask, as I cant find any bugs in relation to it so far.



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Overall Rating: 5 (1 ratings)
Tim Smith Sat, 10/13/2007 - 04:03
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Thanks for the response.. it doesnt look the same though.

The phone that has been placed on hold still receives the music, and we are using G711.

It is actually that the phone loses contact with the active callmanager and eventually fails to the standby. Then normal operation is resumed.

Might have to open a tac case. Definitely looks like a bug but I cant see anything like it in bug tool.



Tim Smith Sat, 05/10/2008 - 04:33
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Now fixed in 4.1(3)SR7

CSCsl51895 - MOH locks up when using MOH with Full duplex streaming True



Rob Huffman Sat, 05/10/2008 - 08:29
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Hi Tim,

Thanks for posting back with the resolution for this rather "odd" issue. 5 points for your good work here!

Take care,



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