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How to tell if there is no cable connection to an FXO port

I have a paging system connected to an FXO port on a 2821 ISR.  Users complained today that they get busy when they dial the paging number.  There have been no config changes. This was working yesterday.  Resetting the port did not resolve the issue.   They are doing construction at this site - I suspect the line has been cut.  Is there a way I can tell if there is nothing connected to the FXO port without being at the site (ie remotely)?



Cisco Employee

Re: How to tell if there is no cable connection to an FXO port


There isn't an easy way to remotely check the analog circuit for a cabling issue.  You best bet is to run a couple debugs which can get you to look at the analog level:

debug voip ccapi inout

debug vpm sig

You should see a 'wait for dial tone' state on the VPM debugs and pass a q.850 call failure with no circuit available if there is an issue with the line.

The only fool proof way to ensure it isn't an issue with the FXO port itself is to have them plug an analog handset into the line that is currently in the router, and see if you can get the analog phone to make the call to the paging system.

-Steve Holl

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