Solved: MGCP Fractional PRI

chris.damore · ‎04-13-2007

How do you configure MGCP to support a fractional PRI? It keeps changing the pri-group on the controller to all 24 channels.

pkentsmith · ‎04-20-2007

Cisco DO NOT support the use of MGCP with fractional E1's. This said, there is an UNSUPPORT work around which allows you to specify in call manager which channels are available, see below: -

Within the advanced CallManager service parameters (not shown by default) there is a field called "Change B-Channel Maintenance Status 1" which can be altered to mark channels out of service. The string below will need altering depending on how many channels are in use (0 = available, 1 = unavailable). The string below is an example for 20 channels.

Change B-Channel Maintenance Status 1 as follows:

S0/DS1-0@SDA123456789ABC = 0000 0000 0000 0000 0000 0111 1111 1111

Regards

PKS

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thisisshanky · ‎04-13-2007

yes read these threads.

http://forum.cisco.com/eforum/servlet/NetProf?page=netprof&forum=Unified%20Communications%20and%20Video&topic=IP%20Telephony&CommCmd=MB%3Fcmd%3Ddisplay_location%26location%3D.1ddd5a06

http://forum.cisco.com/eforum/servlet/NetProf?page=netprof&forum=Unified%20Communications%20and%20Video&topic=IP%20Telephony&CommCmd=MB%3Fcmd%3Dpass_through%26location%3Doutline%40%5E1%40%40.1dde27df

If using CCM-manager config, i would recommend to remove that command as Callmanager has no idea how many channels are active on the PRI. It will think that its a full PRI and change the config accordingly.

HTh

Sankar

PS: please remember to rate posts!

Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus

john · ‎04-19-2007

MGCP doesn't support fractional PRI's. The only way to get this to work (unsupported) is to not allow CM to download MGCP changes to the router.

The best solution might be to migrate your gateway to h323.

John

pkentsmith · ‎04-20-2007

Cisco DO NOT support the use of MGCP with fractional E1's. This said, there is an UNSUPPORT work around which allows you to specify in call manager which channels are available, see below: -

Within the advanced CallManager service parameters (not shown by default) there is a field called "Change B-Channel Maintenance Status 1" which can be altered to mark channels out of service. The string below will need altering depending on how many channels are in use (0 = available, 1 = unavailable). The string below is an example for 20 channels.

Change B-Channel Maintenance Status 1 as follows:

S0/DS1-0@SDA123456789ABC = 0000 0000 0000 0000 0000 0111 1111 1111

Regards

PKS