CCME - FXO - outgoing calls answers incoming one

[aobszynski]

There is 2621xm with CCME on c2600-advipservicesk9-mz.123-8.T3.bin software. There is NM-HDA-4FXS+8FXO

module and simple configuration...

Sometimes (2-5 times per day) ppl calling out from

7960/7905 "magicly" answers call already coming in.

Debuging trunk group shows that voice port is selected after interdigit timeout and called number matches dialout peer.

Here is dp example:

trunk group tocity

voice-port 1/0/4

trunk-group tocity

connection plar opx 101

caller-id enable

!

voice-port 1/0/5

trunk-group tocity

connection plar opx 101

caller-id enable

!

voice-port 1/0/6

trunk-group tocity

connection plar opx 101

caller-id enable

dial-peer voice 1 pots

trunkgroup tocity

destination-pattern 9T

!

What to do to solve that ?

Those lines are FXO in Euro area.

[jbouwkamp]

Not sure about Euro but in the US you occasionally run into this with loopstart lines, its called glare. If someone is calling in at the exact time that the router tries to dialout on a port you happen to answer the call by accident. Groundstart lines do not have this problem as they have better signaling occur between the CO and router. The best thing you can do is find the exact hunt group order from telco and make your preferences on outgoing calls the opposite. In other words have outgoing calls use the last port in an incoming hunt group first so that the chances of glare are minimized.

[patsbc]

Voice port and DP configuration looks fine.

I've seen similar issues with FXOs outside of a trunk-group. Oddly enough - I've put a call inbound via a connection plar opx and had it seize an outbound voice-port which would then get me a PSTN redirect after a short delay - "Please hang up and try your call again."

This was also on 12.3(8)T. I was never able to trace it down to the source of what caused it, because it happened infrequently. I did not make any configuration changes. If you determine the source, please post your findings.

Pat