same PRI channel always selected!

Unanswered Question
May 23rd, 2008
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I've got a 2801 MGCP gateway with a VWIC2-1MFT-T1/E1 configured as a PRI and using bottom-up channel selection.

All 23 channels are administratively up. The first call is successful and used channel 23.

When channel 23 is in use I can see subsequent calls come into the gateway - even saying that is will use channel 22. However, the "debug isdn q931" output shows that it actualy tries to use channel 23 and fails with:

"May 23 07:54:05.271 MDT: ISDN Se0/2/0:23 Q931: RELEASE_COMP pd = 8 callref = 0x81A7

Cause i = 0x80AC - Requested circuit/channel not available"

We are using switch type DMS-100 and the Telco confirms that is correct. My gear is the user, the telco is network.

Anyone with a suggestion as to what I should try? Changing to top-down channel selection results in no calls going through.


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paolo bevilacqua Fri, 05/23/2008 - 07:31
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Hi, if you can take complete trace it would help, because you are omitting to mention if "subsequent calls" are in or out, etc.


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