07-15-2013 03:00 AM - edited 03-16-2019 06:22 PM
I just installed a new Cisco Call Manager (replaced a Nortel) and the only complaint I have heard is that when someone calls from the PSTN to a person in the office the caller hears a ring back 3 to 4 times before the phone in the office rings. I can see the call hit my router as soon as the caller hears the first ringback. Is there soemthing I have to configure to speed the call to the desk phone?
07-15-2013 03:34 AM
You did not specified any detail like type of line, configuration, system and version, protocol used.
07-15-2013 04:15 AM
Sorry, you're right. I am using an E1 PRI on a 2901 connecting to Call Manager 8.6.2.
Here's the E1 config:
controller E1 0/1/0
pri-group timeslots 1-31
!
interface Serial0/1/0:15
description Dresden PSTN Access
no ip address
encapsulation hdlc
isdn switch-type primary-net5
isdn incoming-voice voice
trunk-group PSTN_ALL
no cdp enable
!
07-15-2013 05:16 AM
Seem like you have and H.323 configuration, you did not include the dial-perr configuration for CM, anyway you will need need to take "debug isdn q931" and "debug cch323 h225" with "term mon".
07-16-2013 12:40 AM
Hi Paolo,
I'm not sure what the cause was, I have not changed anything, but the problem seems to have resolved. Could the system have needed some breaking in time? This was a new install and I posted this on day 1.
07-16-2013 12:47 AM
It's impossible to tell why without more information.
Anyway, in Germany you need isdn overlap-receiving configured.
07-16-2013 12:52 AM
Why is that needed? It looks like it would only serve to slow the call routing down further.
07-16-2013 01:04 AM
Try calling from a phone at home, pause 1 or 2 secs in the last digits, and you will see why it is needed.
07-23-2013 07:19 AM
Hi Paolo,
Thanks for the advice on for the overlap-receiving, that helped a bunch. I am still having a problem though with some inbound calls taking upward of 30 seconds to connect. The worst of it is that there is no ringback tone during that time so customers are thinking there is something wrong and hang up. Any advice for that?
07-23-2013 09:03 AM
As mentioned above, one need to see the traces for a troubled call.
08-05-2013 06:34 AM
Paolo,
The missing piece was a timeout on the overlap receiving. Here's what I did:
isdn overlap-receiving T302 5000
Thanks for your help!
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