Showing results for 
Search instead for 
Did you mean: 

Community Helping Community


SIP to FXO not working

I have have 2 UC series boxes connected via SIP dial-peers.  Read as simple site-to-site peers.

Box 1 has an FXO port connected to the PSTN.

If a call comes in from box 2 via the SIP dial-peer, with digits matching the destination-pattern of the POTS dial-peer, the call fails.

If I attempt to dial the same pattern from a registered SCCP phone on box 1, the call succeeds via the POTS line.

I also tested with x-lite SIP client pointing it to an inside IP of box 1 dialing the same pattern and the call failed to complete via the POTS.

Also on Box 1 I have a SIP trunk to an ITSP and all calls to that trunk via any phone, including unregisterd x-lite, complete successfully.

It is only when I attempt an outbound call that is SIP to FXO.


Cisco Employee

SIP to FXO not working

Have you taken any debugs on box 1 for a failed call?  Are you sure you are hitting the correct pots dial peer?  We would need to see the following debugs to determine why the call if failing:

debug voip ccapi inout

debug ccsip mess

debug vpm sig

You dial-peer config would be needed as well.


SIP to FXO not working

Thanks for the debug commands.

I figured it out...I was missing a dial-peer for the SIP leg of the call.  The system had VOIP dial-peers for patterns prefixed with '9', but this particular pattern was prefixed with '8' to force the call to the FXO port rather than use the SIP trunk.

CreatePlease to create content
Content for Community-Ad
FusionCharts will render here