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Wierd FXO behaviour


I have a 4 port FXO card in an 1861 runnign as a h323 gateway fo CUCM7.X.  Two lines connected into it, one is the main line number and the other is a dedicated line for hte fax.  I have the main line in 0/1/0 and the fax in 0/1/2.

Wierd problem is that when the main line number rings out, the RNA settings on the phone don't take effect.  When the main line rings out, when I do a "sh voice port sum" i see the 0/1/0 going to ring-det when the phone is ringing, but then I see 0/1/1 (which has nothign conected to it) going off hook, then 0/1/2 going off hook, then the original port 0/1/0 goin off-hook and then disconnects.  The ports then stay in off-hook status.

I have plar opx configured on the main line and on the fax line so there's no reason why it would go onto 0/1/1 at all, let alone 0/1/2.

Any help appreciated,



Hall of Fame Super Gold

Re: Wierd FXO behaviour

When strange, unexplicable things happens in cisco routers.

1. reload

2. if still happens, update image.

I know is not a scientific approach and many will not agree with this method, but being honest, it helped very very many times in my career.

Re: Wierd FXO behaviour

This might be a layer1 trouble.  If FXO lines are 'double punched' or 'crossed' meaning the tip or ring overlaps two FXO lines you will get strange behaviour such as two FXO ports showing activity when only one was dialed.  I have also seen where you make a call out and the call actually goes out two lines at the same time.

Trying a reload sounds like a good thing to try also.


-- please remember to rate and mark answered helpful posts --
Cisco Employee

Re: Wierd FXO behaviour

I agree with Brandon.  Sounds like a wiring mistake.

Make sure you have two-wire wired straight-through to the port.