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Community Member

CallManager 5.1 no conference bridge available / cannot complete conference

CM 5.1, Conferencing was working at one point, the servers were rebooted and now conferencing does not work, received no conference bridge available error message when trying to complete conference, found the CM was advertising g722 codec, disabled that function. Now receiving cannot complete conference error message, rebooted IP voice streaming media services, reset conference bridges, both are registered, anybody got any other ideas on why this is not fuctioning properly??

Thanks ahead of time...

Community Member

Re: CallManager 5.1 no conference bridge available / cannot comp

No Available Conference Bridge


The following message displays: No Conference Bridge Available.

Possible Cause

This could indicate either a software or a hardware problem.

Recommended Action

1. Check to see whether you have any available software or hardware conference bridge resources that are registered with Cisco Unified CallManager.

2. Use the Cisco Unified CallManager Real-Time Monitoring Tool to check the number of Unicast AvailableConferences.

The Cisco IP Voice Media Streaming application performs the conference bridge function. One software installation of Cisco IP Voice Media Streaming will support 16 Unicast Available Conferences (three people/conference), as shown in the following trace.

To make a call between two devices that are using a low bit rate code (such as G.729 and G.723) that do not support the same codec, you need a transcoder resource.

Assume Cisco Unified CallManager has been configured such that the codec between Region1 and Region2 is G.729. The following scenarios apply:

?If caller on Phone A initiates a call, Cisco Unified CallManager realizes it is a Cisco Unified IP Phone model 7960, which supports G.729. After the digits are collected, the Cisco Unified CallManager determines that the call is destined for User D who is in Region2. Because the destination device also supports G.729, the call gets set up, and the audio flows directly between Phone A and Phone D.

?If a caller on Phone B, who has a Cisco Unified IP Phone model 12SP+, initiates a call to Phone D, this time the Cisco Unified CallManager would realize that the originating phone only supports G.723 or G.711. Cisco Unified CallManager would need to allocate a transcoding resource so audio would flow as G.711 between Phone B and the transcoder but as G.729 between the transcoder and Phone D. If no transcoder were available, Phone D would ring, but as soon as the call was answered, the call would disconnect.

?If a user on Phone B calls Phone F, which is a Cisco Unified IP Phone model 12SP+, the two phones would actually use G.723, even though G.729 is configured as the codec to use between the regions. G.723 gets used because both endpoints support it, and it uses less bandwidth than G.729.

Community Member

Re: CallManager 5.1 no conference bridge available / cannot comp

Do you have any region/location cofiguration? Since your system runs at single site, you don't need these configurations. If you only use CCM software conference bridge, location/region/codec are the reason of problems usually.

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