FXO hang on problem

Unanswered Question
Sep 6th, 2007


We have a CM4.1.3 and 2811 voice gateway. We use a third party auto attandant, but we had the problem with CM auto attandant too.

Sometimes we try to call outside and we get busy tones. Then i use the command "sh call active voice brief" and see some FXO ports are open and one of the call leg ip address is auto attandant machine's. So call is up for 3 hours between fxo and auto attandant. The problem is also seen with CM auto attandant. How can i solve this issue.

I have this problem too.
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Paolo Bevilacqua Thu, 09/06/2007 - 05:37


this is the FXO disconnect problem. However, the call showul close after a certain time, which IOS are you using ?

The document that explains the issue is:


Note: in most countries the only configuration you can use is TONE DISCONNECT DETECTION, other tecniques won't work.

Hope this helps, please rate post if it does!

Paolo Bevilacqua Thu, 09/06/2007 - 06:10

That is fine. Check with "debug vtsp signal" if telco is doing any hardware signalling on the line to indicate disconnection, but as I said that is unlikely, so you will have to configure tone-based detection based on the country you are in.


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