Random dropped calls

[vuk]

Hello friends,

I am experiencing a very annoying and hard to explain (at least for me) problem with calls being dropped for no obvious reason at no specific time. Call can be dropped even during ringing the queue.
My setup is as follows:

1. Pbx appliance PC intel based with 4 intel NICs with latest version 3cx enterprise licence (linux version)
2. MikroTik RB1100 router (internal traffic not routed. Only external)
2. TP-Link POE Switch
3. Yeastar GSM Gateway
4. SIP trunk with telecom
5. 14 HTek UC924 phones (provisioned)
6. 2 Linksys SPA924 phones (unprovisioned)

Calls are being dropped at any time, no matter inbound or outbound and no matter which extension and which external line. I can see this in activity log:

03/23/2020 1:34:07 PM - x-call-control DROP: call is not found:

or this:

03/23/2020 1:34:07 PM - [CM503003]: Call(C:310): Call to <sip:[email protected]:0> has failed; Cause: 487 Request Terminated/INVITE from 10.213.8.184:5060

while I have no idea what does this mean. Its a bit different from Asterisk.

Anyone experienced such thing and knows how to solve?

Best Regards.

 

[eddv123]

GSM Gateway

No different from a mobile call really (bar the fact you are moving around less) possibly a drop in signal I think.

What is IP 10.213.8.184 ?

 

[vuk]

No different from a mobile call really (bar the fact you are moving around less) possibly a drop in signal I think.

What is IP 10.213.8.184 ?

Hello there. Thanks for reply...

It does not matter which external line is used. It happens the same with telekom sip trunk. To be honest, these calls going via GSM gateway are more stable than telekom sip trunk but however, calls are dropped on any external line. We have not experienced local call being dropped... yet.
The address You asked for is a phone address.

Any more ideas?

Best Regards.

 

[eddv123]

OK, in this case if it were me I would simply run a wireshark capture: https://www.3cx.com/docs/capture-network-traffic/

Due to the random nature of this a longer time frame capture would be required using tshark or dumpcap possibly: https://www.wireshark.org/docs/man-pages/dumpcap.html

I guess the key question is how random is random ?

 

[vuk]

OK, in this case if it were me I would simply run a wireshark capture: https://www.3cx.com/docs/capture-network-traffic/

Due to the random nature of this a longer time frame capture would be required using tshark or dumpcap possibly: https://www.wireshark.org/docs/man-pages/dumpcap.html

I guess the key question is how random is random ?

Many thanks for fast reply!

Well, to be honest, I don't know the answer. Can I use tcpdump?

Best regards.

 

[eddv123]

Yes same thing, If you have the logging running on 3CX, you may want to investigate the support info file/binary log viewer: https://www.3cx.com/docs/3cx-log-viewer/

However I often find that for call dropping/quality related issues you cant beat Wireshark.

 

[vuk]

Yes same thing, If you have the logging running on 3CX, you may want to investigate the support info file/binary log viewer: https://www.3cx.com/docs/3cx-log-viewer/

However I often find that for call dropping/quality related issues you cant beat Wireshark.

It seems the logging is active but there are soooo many logs. Which one to open?

 

[eddv123]

Open up the support info file and look at the files BLDEF/BLREC, this is covered in the guide I posted.

 

[vuk]

Open up the support info file and look at the files BLDEF/BLREC, this is covered in the guide I posted.

Ok, I'm on it now. Thanks for the guide!

 

[vuk]

Good day there...

Unfortunately, I'm not finding any clear reason in the log. All that is suspicious to me is this:

03/24/2020 10:59:15 AM - x-call-control DROP: call is not found: ywMjMNz3dX5gFbe0yKsobQ..;from-tag=ccbac139;to-tag=aca39638

03/24/2020 10:59:15 AM - x-call-control DROP: call is not found: GswFSK2Vnk-kPf5daxd2yg..;from-tag=56543c2a;to-tag=fb8c8c3f

03/24/2020 10:59:15 AM - x-call-control DROP: call is not found: XckwvpyBfXhvpIiv_BKQGg..;from-tag=67c3b529;to-tag=b5975f76

03/24/2020 10:59:15 AM - x-call-control DROP: call is not found: yFNZlUNeXYvu4Lg1vn8vAQ..;from-tag=d923ad62;to-tag=1b6ebc31

Do You know what does this mean?