I have a CUCM 6.1 install, using a 2811 with MGCP to telco.
The site is in the middle of nowhere, so the only circuit they can provide is a voice T1 off of a "1A" switch. I am not familiar with a 1A switch, but appearantly it is pretty uncommon and old. I ordered the circuit as a wink start e&m circuit. What was delivered is the following:
Channels 1-14 are incoming DID channels, wink start.
Channels 15-24 are, as per the telco, "just like pots lines...dial tone"
Incoming works fine, but outbound is not working properly. When I call out, the call will ring, but when the caller answers, it does not show as a connected call. The voice path is established, but if you view the phone, it still shows "Ring Out" and if you show the voice port in the router, it shows EM_Wait_For_Answer.
Does anyone have any suggestions where to begin? Telco insists that this is the only way this circuit will work.
Have you tried h323 config. Here is a snippet of a h323 config that I hooked up in a similar situation. The first 14 channels where incoming only and the last 10 channels where outgoing only.
controller T1 0/2/0
cablelength long 0db
ds0-group 0 timeslots 1-14 type e&m-wink-start dtmf dnis
ds0-group 1 timeslots 15-24 type e&m-wink-start dtmf dnis
dial-peer voice 5 pots
description voip dial peer to PSTN
Not really what you are asking for but it might help.
this might seem way out of it
try using H323 and ensure you have the "h323-gateway voip bind srcaddr
i experienced an issue with similar (NOT EXACTLY LIKE )this already which was a routing/Firewall issue.
The provider may not be doing immediate start rather than wink-start.
If the other 15-24, you may want something like this:
controller t1 0/0/0
ds0-group 0 time 1-14 type wink-start(or immediate)
ds0-group 1 time 15-24 type fxo-loop-start
That's what I think of when they say pots dial tone.
Thanks for the helpful info guys. I am getting closer, but still having problems. I configured the first channel group for E&M wink start, and configured the outbound channels for FXO-Ground start as requested by telco.
Outbound does not work. I can confirm in debug that I am sending the proper digits and accessing the correct channel, but all I get is a busy signal.
Incoming works to an extent. If I call into an IP phone over the T1, I can answer the call and works fine. When I hang up the IP phone, the remote side does not disconnect for an additional 10 seconds. Minor issue but I would still like to resolve this.
Hi, output of "debug vpm signal" would help for both issues. Havin msec timestams is key as often these are timing issues.
For outgoing, seems like you have ground start configured ? It should be loop start in 99% of the cases. Still looking at incoming trace.
Right, you had specified GS before. I think you also said you're using MGCP and that moves all signalling on the CCM. So I would try an H.323 config where all the signaling is done that the router that rarely is wrong.
Try creating a RG/RL that only uses the first 14 channels and sidesteps the FXO channels, and see if at least inbound and outbound works.
Well, Still working on this one. Inbound works fine.
Telco is stating that the outbound channels are ground start. Should these be configured on the H323 gateway as FXO-GS or FXS-GS?
I have tried both ways with little success.
When using FXO-GS, I can dial out, the called party phone rings for a split second then drops. The calling party just gets fast busy.
channels aren't configurable based on inbound or outbound - the T1 layer 2 is set for the circuit. Below is my T1 config for CAS-T1
controller T1 0/0/0
ds0-group 1 timeslots 1-24 type e&m-wink-start
and in CUCM configure the circuit the same, if that helps.
Please send output of "show controllers T1", you might have a clock issue. Also note, for an H.323 trunk there are no details about the signaling to be entered in the CM. This because the config you sent about the router does not reflect an MGCP configuration.
Well, after a week and a half, two TAC cases and endless hours on the phone with Telco, a resolution was reached.
For starters, I had followed others suggestions and created two DS0 groups, one E&M Wink for incoming and one FXO_Ground Start.
Secondly, Telco had an issue in translations between their CO's.
Third, On my outgoing dial peer I had a "Forward Digits All". This caused issues with variable lenght dial strings, so I had to delete the dial peer and re-add without the fwd digits command.
Thanks to all who offered assistance.