Solved 3CX with Openvox GSM Gateway

[Hind.hk]

Hello,
I have a specific case and i want to know if someone can help me with it.

One of our customers is using 3CX with Openvox GSM Gateway 4 ports, their need is to be able to make inbound and outbound calls, and each GSM port is a specific extension, for this Openvox has made the configuration for them, by creating 4 sip trunks in 3CX, and 4 endpoints in Openvox Gateway.
The inbound calls are working fine, so when calling a number, the right exention rings, but regarding outbound calls, when a specific extension made a call, a random port is chosen, and not necessarly the one related to the extension.
After Openvox team has made an analysis based on Sip logs on the gateway, and testing with their on system (which already use this option), they found that the trunk sip id is not correctly transmitted to the gateway during the outbound call.
In their system, the Sip trunk ID is explicitely in the contact field: [email protected]:5060,so the gateway knew which trunk to use, and in our case on the contact: 192.xx.xx.xx:5060, so the gateway choose the trunk in random way.(see the screenshot)
So my question is what is the parameter that we need to change on 3CX to have the same result?

Thank you so much

 

[eddv123]

This is not the sort of setup I would strictly recommend, firstly the only "supported" GSM model available for 3CX is the beroNet GSM variants: https://www.3cx.com/voip-gateways/

Where this does not mean that the device wont work with 3CX it just means they have not been tested and approved by them.

The other point I would like to make is that this requirement sounds similar to the configuration which is normally raised on the forums for the Patton FXO device(s). Like the thread here: https://www.3cx.com/community/threads/custom-configuration-patton-4114.49691/

As the thread states, inbound is very easy, outbound not so much. And Pattons are supported gateway brands - normally this sort of setup is the responsibility of the gateway vendor.

Regardless you may get some luck by reading (or having the vendor look at) this very detailed guide on how 3CX deals with SIP trunk outbound parameters: https://www.3cx.com/docs/sip-trunk-outbound-calls/

 

[Hind.hk]

Thank you so much.
I will take a look at these links, and see what i can do.

 

[leejor]

Openvox has made the configuration for them, by creating 4 sip trunks in 3CX, and 4 endpoints in Openvox Gateway.

If this is the way, it has been setup in 3CX, then then which trunk to route out on, is determined by the outbound rules and the order the trunks are listed, in those. If it were built as a single trunk group, then calls would appear to be more random. What does your outbound rule(s) look like, for these trunks?

 

[Hind.hk]

I have 4 outbound rules at the top order, each one to route the extension to the specific trunk.
I want to mention that i already did this same configuration for the customers that work with GoIP or Portech GSM gateways, and everything was working fine. First time i had this situation is with Openvox.

 

[leejor]

Is each port (trunk) on the GSM gateway, not determined by the port number ? When the trunks were created in 3CX, the trunks should have been built, something like...10000= port 5060, 10001 = port 5061, 10003 = port 5062, etc. Then a call out on trunk 10000 to the IP of the gateway would use port 5060, the gateway "knows" that that port is associated with the first GSM "line".

 

[YiannisH_3CX]

Hello @Hind.hk

Try navigating to Trunk Settings / Outbound parameters and set Contact: UserPart field to "LineID" Internal Number of line. Since you have 4 trunks you will need to do this to all trunks.

 

[Hind.hk]

Hello,
Please excuse me for not responding before.
Thank you all so much for helping.

This worked.

Best regards

 

[YiannisH_3CX]

Glad to see the issue has been resolved and thank you for the update.