Solved Calls dropping

[Callinectes]

I have one 3CX system that is giving us some serious issues. The users of this system complain that inbound calls are dropping regularly. We have many other 3CX systems configured the same way - with the same SIP provider and in the same hosting environment, but this is the only one giving us these problems with dropped calls. We have done extensive testing at their site and have not found any issues with the network, phones, or SBC. I ran some packet captures and when analyzing a call that dropped I see the BYE coming from the 3CX to the carrier. Could someone take a look at the attached call flow and see if there are any obvious problems?

 

[Callinectes]

Here is the end of the packet capture for that call. Am I correct in assuming that the "destination unreachable" is what caused 3CX to issue the BYE?

40364 183.095153 66.241.x.x 10.0.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0xA80150DA, Seq=53144, Time=2428465024
40367 183.100843 10.0.x.x 66.241.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0x7BC7A598, Seq=24860, Time=266531212
40370 183.115278 66.241.x.x 10.0.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0xA80150DA, Seq=53145, Time=2428465184
40372 183.121292 10.0.0.x.x 66.241.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0x7BC7A598, Seq=24861, Time=266531372
40378 183.135116 66.241.x.x 10.0.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0xA80150DA, Seq=53146, Time=2428465344
40380 183.155092 66.241.x.x 10.0.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0xA80150DA, Seq=53147, Time=2428465504
40381 183.155132 10.0.x.x 66.241.x.x ICMP 242 Destination unreachable (Port unreachable)
40383 183.175088 66.241.x.x 10.0.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0xA80150DA, Seq=53148, Time=2428465664
40384 183.175116 10.0.x.x 66.241.x.x ICMP 242 Destination unreachable (Port unreachable)
40385 183.178091 10.0.x.x 64.2.x.x SIP 531 Request: BYE sip:[email protected] |
40387 183.195100 66.241.x.x 10.0.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0xA80150DA, Seq=53149, Time=2428465824
40388 183.195134 10.0.x.x 66.241.x.x ICMP 242 Destination unreachable (Port unreachable)
40393 183.215189 66.241.x.x 10.0.x.x RTP 214 PT=ITU-T G.711 PCMU, SSRC=0xA80150DA, Seq=53150, Time=2428465984
40394 183.215217 10.0.x.x 66.241.x.x ICMP 242 Destination unreachable (Port unreachable)
40395 183.221337 64.2.x.x 10..x.x SIP 497 Status: 200 OK |

 

[Callinectes]

And this is the response I received from support with this trunk provider: "2021-09-29 11:42:23 Dear Customer, Please disable qualify/options etc and reload your trunk. We don't officially support ICMP and ICMP monitoring on our network. Thank you,"

 

[ChrisC_3CX]

For what port and packets does the 3CX PBX respond with "Destination unreachable"?

Do you happen to have verbose logging mode enabled on the PBX? If yes, go into Dashboard >> Activity Log and use the filter option display info only for this call. Can you see the same SIP messages in the activity log as seen in the wireshark capture?

Could you provide the information mentioned here:

https://www.3cx.com/community/threads/information-to-provide-when-requesting-help.67558/

 

[Callinectes]

I did have verbose logging enabled but that was yesterday. We moved to TCP for SIP and it appears to have helped resolve this issue.

 

[VasilisV_3CX]

Glad to hear the issue has been resolved @Callinectes. Feel free to open a new thread if you require any further assistance or information.