Secondary dialtone on MGCP 2620 FXO outbound; inbound fine

[konigl]

I have a 2620 running Version 12.1(5)YD5 set up as an MGCP gateway. FXO ports set as loop start, both ports are connected to POTS lines. Router has 16MB flash, 48MB DRAM. CallManager system is 3.0(12).

On outbound calls, with route pattern 9.@ and pre-Dot digit discard, I get to the gateway; the called phone rings for a split second then stops, as though the calling device has decided to hang up, but the call was long enough that I can see the number of the calling gateway's POTS line in Missed Calls. Meanwhile, as soon as the call has hung up, I hear outside world dialtone (from the gateway) on the calling phone. If I then re-input the same 10-digit phone number, the called number rings as it should, until answered.

Same outbound call and route pattern with no digit discard, I hear outside world dialtone (from the gateway) on the calling phone first (i.e. no half-ring then hangup). If I then re-input the same 10-digit phone number, the called number rings as it should, until answered.

On inbound calls to the phone number of the POTS line on the gateway, everything works as intended -- the call rings at the designated attendant's phone, as configured in CallManager.

Am I missing something in the router config or in CallManager that would let the outbound call go through without having to enter the number twice? Or is this something that an IOS upgrade will fix? (I have been resisting the IOS upgrade approach since I already tried to go to the latest, and found it wouldn't let me load it with only 48MB RAM).

Will try H323 gateway configuration next, while waiting for feedback.

-Larry Konig

[marinaibm]

Hi,

If it was h323 i would say you should add "forward-digits all" under your pots dial-peer.Dont think it will work for mgcp though ..:(

marina

[konigl]

Hit a snag in setting up my router as H323 gateway: router is set up to route among several 802.1Q VLANs, so I have my IP addresses on subinterfaces, but the h323-* commands want to be applied at the interface level. Hmm, I remember seeing something somewhere about H323 and virtual interfaces, anybody run into this problem too and resolved it?

-Larry

[Vance Krier]

Create a loopback adapter with Ip address, then h323 bind to that address. Don't forget to change your gateway IP in CallManager if that's what you're doing.

Good Luck,

Vance

[konigl]

Thanks for the tip Vance. It works!

I am now using H.323 for outbound 911 calls, with partitions and calling search spaces set up to direct these calls to the appropriate local gateway.

Inbound return calls on the POTS lines from the 911 center are directed to the front desk of each building using "conection plar", which I picked up somewhere else in the forums.

Never did figure out what was the issue with MGCP on the outbound calls. One thing I do miss about using MGCP was the ability to address a specific gateway down to the FXO port level; H.323 limits me to addressing the whole router as the gateway.

Thanks again for pointing me in the right direction.