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PRI dialout problem


Here is the situation, not sure if it would work.

I have a 3640 connected to a PRI using 2MFT1 card sitting inside a HDV module. One port connectes to the PRI and the other port is connected back-to-back

to a controller port on a 3620 which is housing the digital modem bank.


What i want to do is route the moden calls (based on DIDs) to the 3620 and route voice calls to the call manager at the 3640 router.

Everything seems to be working fine, EXCEPT

I am not able to dial out using the digital modem bank ( we have to dial out once in a while to other unix boxes). When i try to dialout (reverse telnet) ATDT command, debug shows no carrier.

But i can dialin through the pri and the modems in the digital modem banks respond and negociate.

when i dial outside, debug also shows me that the call goes from 3620 to 3640 and then to the PRI, but for some reason i get no carrier error.

any ideas?

also do i need "incoming-call modem" command



Re: PRI dialout problem

To hairpin the calls between the PRI you will need the 'isdn incoming-voice voice/modem' command to allow the voice port pass the voice bearer cap in the setup message.

Make sure your POTS dial peers that point to the modem bank has 'direct-inward-dial' to allow the single stage dialing

Also for the outgoing POTS dial peer (pointing to the PSTN) ensure you prefix NNN or forward-digits all to allow any explicity matched digits to be prepended back on the outgoing called number.

If this still does not help do a debug isdn q931 on the 3640 and make the call from the modems - this will tell us everything that is going on.