Inbound calls are dropping immediately

[shu07]

If I setup 3cx to forward my inbound calls to an IVR, voicemail, or even a direct extension, all the calls drop immediately within 1 to 2 seconds. If the call goes to an extension, the SIP phone recognizes an incoming call for just a few milli-seconds, and never stays connected enough to let a ring tone come through. Dialing outbound is not an issue, nor the internal IVR #, or other extensions, from multiple SIP phones internally (android phone (3cx, sipdroid) + Xlite combinations).

I got similar behavior when I tried pfsense with freeswitch for inbound (possibly a configuration issue as well on my end). I am using flowroute as my SIP trunk provider.

Below is my log:

20:38:28.703 [MS210001] C:7.2:Answer received. RTP connection[unsecure]: 127.0.0.1:40620(40621)
20:38:28.703 Remote SDP is set for legC:7.2
20:38:28.609 [CM503008]: Call(7): Call is terminated
20:38:28.562 [CM503025]: Call(7): Calling Ext:Ext.8000@[Dev:sip:[email protected]:40600;rinstance=737240aa4ae642ab]
20:38:28.562 [MS210002] C:7.2:Offer provided. Connection(transcoding mode): 127.0.0.1:7020(7021)
20:38:28.546 [CM503004]: Call(7): Route 1: Ext:Ext.8000@[Dev:sip:[email protected]:40600;rinstance=737240aa4ae642ab]
20:38:28.546 [CM503010]: Making route(s) to <sip:[email protected]:5060>
20:38:28.546 [MS210000] C:7.1:Offer received. RTP connection: 4.55.17.2:9860(9861)
20:38:28.546 Remote SDP is set for legC:7.1
20:38:28.546 [CM505003]: Provider:[Generic SIP Trunk -] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [] PBX contact: [sip:[email protected]:5060]
20:38:28.515 [CM503001]: Call(7): Incoming call from +15555555555@(Ln.10000@Generic SIP Trunk -) to <sip:[email protected]:5060>
20:38:28.500 [CM503012]: Inbound out-of-office hours rule (unnamed) for 10000 forwards to DN:8000
20:38:28.500 Looking for inbound target: called=+14444444444; caller=+15555555555
20:38:28.500 [CM500002]: Info on incoming INVITE:


Key:
8000 = Extension for IVR
33333333 = User Account Name on SIP Registration
4444444444 = DID #
5555555555 = source device's # that dialed the call outbound to DID #

12.12.12.12 = WAN IP
192.168.5.250 = LAN IP Address that C3X is binded to

I am forwarding 5060 UDP from my router to this C3x box. Any advice would be very much appreciated!

 

[sigma1]

Did you route ports 9000 to 9050 as well?

 

[shu07]

I set the RTP range from 9000 to 9003. I port forwarded UDP 9000 to 9003 onto the LAN interface. If I restart all the services, and make a call, same sort of issue occurs:


10:57:26.106 [MS210000] C:1.1:Offer received. RTP connection: 4.55.17.2:9720(9721)
10:57:26.106 Remote SDP is set for legC:1.1
10:57:26.106 [CM505003]: Provider:[Generic SIP Trunk -] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [] PBX contact: [sip:[email protected]:5060]
10:57:26.106 [CM503001]: Call(1): Incoming call from +15555555555@(Ln.10000@Generic SIP Trunk -) to <sip:[email protected]:5060>
10:57:26.106 [CM503008]: Call(1): Call is terminated
10:57:26.106 Currently active calls - 1: [1]
10:57:25.684 [CM503012]: Inbound out-of-office hours rule (unnamed) for 10000 forwards to DN:8000
10:57:25.669 Looking for inbound target: called=+14444444444; caller=+15555555555
10:57:25.653 [CM500002]: Info on incoming INVITE:



If I redo the call:

11:03:26.747 [MS210000] C:2.1:Offer received. RTP connection: 4.55.17.2:19956(19957)
11:03:26.747 Remote SDP is set for legC:2.1
11:03:26.747 [CM505003]: Provider:[Generic SIP Trunk -] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [] PBX contact: [sip:[email protected]:5060]
11:03:26.747 [CM503001]: Call(2): Incoming call from +15555555555@(Ln.10000@Generic SIP Trunk -) to <sip:[email protected]:5060>
11:03:26.731 [CM503008]: Call(2): Call is terminated
11:03:26.716 [CM503012]: Inbound out-of-office hours rule (unnamed) for 10000 forwards to DN:8000
11:03:26.716 Looking for inbound target: called=+14444444444; caller=+15555555555
11:03:26.716 [CM500002]: Info on incoming INVITE:


IF I redo the call again:

11:07:01.169 [MS105000] C:3.1: No RTP packets were received:remoteAddr=4.55.17.2:13356,extAddr=0.0.0.0:0,localAddr=12.12.12.12:9000
11:06:59.981 [MS210003] C:3.1:Answer provided. Connection(transcoding mode[unsecure]):12.12.12.12:9000(9001)
11:06:59.981 [MS210001] C:3.2:Answer received. RTP connection[unsecure]: 127.0.0.1:40610(40611)
11:06:59.981 Remote SDP is set for legC:3.2
11:06:59.950 [CM505001]: Ext.8000: Device info: Device Identified: [Man: 3CX Ltd.;Mod: 3CX IVR;Rev: General] Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [3CX IVR] PBX contact: [sip:[email protected]:5060]
11:06:59.950 [CM503002]: Call(3): Alerting sip:[email protected]:40600;rinstance=d44328221eb70278
11:06:59.575 [CM503025]: Call(3): Calling Ext:Ext.8000@[Dev:sip:[email protected]:40600;rinstance=d44328221eb70278]
11:06:59.559 [MS210002] C:3.2:Offer provided. Connection(transcoding mode): 127.0.0.1:7000(7001)
11:06:59.309 [CM503004]: Call(3): Route 1: Ext:Ext.8000@[Dev:sip:[email protected]:40600;rinstance=d44328221eb70278]
11:06:59.200 [CM503008]: Call(3): Call is terminated
11:06:59.200 [CM503010]: Making route(s) to <sip:[email protected]:5060>
11:06:59.200 [MS210000] C:3.1:Offer received. RTP connection: 4.55.17.2:13356(13357)
11:06:59.200 Remote SDP is set for legC:3.1
11:06:59.184 [CM505003]: Provider:[Generic SIP Trunk -] Device info: Device Not Identified: User Agent not matched; Capabilities:[reinvite, replaces, able-no-sdp, recvonly] UserAgent: [] PBX contact: [sip:[email protected]:5060]
11:06:59.137 [CM503001]: Call(3): Incoming call from +15555555555@(Ln.10000@Generic SIP Trunk -) to <sip:[email protected]:5060>
11:06:59.075 [CM503012]: Inbound out-of-office hours rule (unnamed) for 10000 forwards to DN:8000
11:06:59.075 Looking for inbound target: called=+14444444444; caller=+15555555555
11:06:59.075 [CM500002]: Info on incoming INVITE:

It fluctuates on the amount of debug messages it produces, but the call is terminated message seems to be coming in much earlier than the rest of the messages following it. Outgoing calls are still working after the port forwarding of RTP ports.

 

[shu07]

Thanks for the tip on the RTP as a point of investigation.

For those who may run into this issue, here is what I did to fix it:

1. Disable STUN
2. Set inbound registration manually on flowroute, while keeping outbound via SIP registration
3. Set 3CX to outbound SIP registration only
4. Forward UDP 5060 + RDP 9000-9003 to LAN interface using Static Ports Only.

Incoming and outgoing calls work perfectly now. Thanks!