Extensions Constantly Registering and Unregistering ID:4101

[Edward Shin]

Are those port ranges that can't quite be seen on the right 9000 to 10999 or 9000-10000? There was a change in the number of RTP ports required in the upgrade from 14 to 15 and I wonder if both your firewalls (PBX and your cellular modem) have had exactly the same change of port range following the upgrade. For example, if your PBX was on 9000-10999 and your cellular modem 9000-10000 (or vice versa) you would potentially have some problems.

For info / security, a lot of those ports you have open only require "UDP" rather than "Both" under Protocol. Details here:

https://www.3cx.com/docs/manual/firewall-router-configuration/#h.tv64ako3hpg9

It might be worth removing all firewall rules that relate to 3CX, create new ones and ensure that both firewalls RTP ports marry up.

Those port ranges are 9000-10999, the port changes were pushed to all our deployed cellular modem units. I then made the change on our PFSense firewall side to open up 9000-10999 as well.

I believe the ports are correct. Unfortunately removing firewall rules isn't an option as we have hundreds of deployed cellular modems/speakers/cameras all over and many of them having unique firewall rules for that specific surveillance site.
We were having audio issues before we made the 9000-10999 port change but that has since been resolved. The registering and unregistering has been consistent since I joined this company, over 3 months ago.

 

[Lee Cramman]

Those port ranges are 9000-10999, the port changes were pushed to all our deployed cellular modem units. I then made the change on our PFSense firewall side to open up 9000-10999 as well.

I believe the ports are correct. Unfortunately removing firewall rules isn't an option as we have hundreds of deployed cellular modems/speakers/cameras all over and many of them having unique firewall rules for that specific surveillance site.
We were having audio issues before we made the 9000-10999 port change but that has since been resolved. The registering and unregistering has been consistent since I joined this company, over 3 months ago.

OK - sounds like a red herring then.

 

[securite]

Have you checked your TCP session timers and SIP client registration interval ?

 

[Edward Shin]

Have you checked your TCP session timers and SIP client registration interval ?

Sorry but how can I check on both of those.
I see in the settings of our main SIP trunk that there is a re-register timeout set to 30.

 

[securite]

The SIP trunk registration should have nothing to do with the endpoints re-registering.

You would need to search for those settings depending on your firewall and SIP UA. In this case the SIP endpoints (either physical phones or soft phone clients) will have the ability to change the re-registration interval. Depending on the time setting, the clients should be re-registering every time their timer expires.

With regards to cellular modems you may be running into a carrier NAT issue whereby there are nested NAT and session timers that may be causing issues.

My recommendation would be to setup a "sandbox" to test with going from a wired internet connection with a static IP to replicate your setup registering a client back to the main PBX. If the issue does not occur in that instance, I would then capture packets using Wireshark or something similar and view the SIP messaging at the PBX side as well as the client side. You should be able to track down the issue in a step wise fashion.