Hi everyone,

i've configured a Vigor IPPBX 2820 with SIP trunk. The ISDN 1 BRI is set to S0 (NT) and it is connected to an ISDN PBX. Everything works fine, outgoing and incoming calls. There is only one problem.

If an incoming call is oncall, it's not possible to receive another call. In fact the other incoming call will FAIL. Call Detail Records says that the call failed and I can hear the PBX that hangs up the call.

It is possible to make simultaneously an incoming and outgoing call without problems.

I've configured SIP trunk to forward incoming calls to extension 903 with appropriate MSN.

How can i resolve this issue?

Do I have to set another ISDN extension with same MSN but with extension num. different?

In this way I can create a group that contains ext. 903 and the new created and i can forward incoming calls to that group.

Suggestions?

Thank

Best Regards

Hi,
There's some Updates


i'm always in trouble with that issue.
I've done some debugging and discovered that seems to be a bug.
What i've tried is this type of scenario:

Incoming/outgoing call through ISDN1 port, configured as S0 (NT). The call works fine, and the green led is blinking when the call is running. If i try to make another outgoing call, if the vigor receives an incoming call or if i call the 903 extension during the ongoing call the Vigor gives me Busy tone.

Analyzing the log i can see that this behaviour:

SIP gives me Busy Here message. (voip debug show -w) and ISDN log (log -i) does not seems to receive any request to initiate the communication. So the call is interrupted by SIP.

It seems to be some difficulties between SIP<--->ISDN logical negotiation during ISDN call.

I've also enabled the Call Waiting function on ISDN1 port but nothing changes.

No one had some experience interfacing ISDN PBX and Vigor 2820 IPPBX?

Thanks

Resolved the issue.

I will never know the reason wht of this problem.

I've reprogrammed the Vigor after a factory reset and everything works fine.

Thanks