Unable to make and receive calls - new install- on prem with OPTUS SIP

[sajpet]

Hello,

We just installed 3cx. We are unable to make and receive calls, however when we changed SIP providers we were able to make and receive calls.

Is there any config details anyone can provide so 3cx can connect with OPTUS SIP.

Appreciate any guidance.

 

[Alphabetic]

I would have gone with a supported SIP provider

https://www.3cx.com/partners/sip-trunks/

You would have to deep dive in to the logs/wireshark to see why calls arent working.

 

[sajpet]

I would have gone with a supported SIP provider

https://www.3cx.com/partners/sip-trunks/

You would have to deep dive in to the logs/wireshark to see why calls arent working.

Thanks, OPTUS is largest TELCO provider in Australia. Surprising 3cx doesn't support OPTUS SIP. I am sure someone in Australia who has used OPTUS SIP with 3cx will know exactly what to do.

 

[Clint-ConnectedOutWest]

Optus SIP will work.
You will need 3CX to be deployed as On Prem due to Optus using their own SIP Endpoint on site.

You will need to apply a static route on your 3CX device routing all traffic to the Optus supplied SIP Signaling IP via the IP of the IP of the managed Optus Router.
ie. xxx.xxx.xxx.xxx/24 -> 192.168.0.x
In my experience, the Optus default for their gateway is 192.168.0.100, but they can change this to fit your local IP requirements.

Once you have the static route set, you will need to configure the trunk as a generic trunk in 3CX, using the Supplied SIP signalling IP from Optus


Authentication is not required/IP Based


Set your main trunk number. Optus uses standard 10 digit format ie 0X XXXX XXXX




Call options as per image



This should get you going.

 

[Voip-Guy]

If you are unable to route directly from the 3cx system from the carrier network, you can also user a Cisco router with a CUBE configuration that will act as a bridge between your carrier and the 3cx system, one the local interface you will have your 3cx and on the second interface your carrier ip network is connected, here is a sample configuration I pulled from WOCOM a local ITSP in Jamaica, configuration can apply for any carrier delivering sip trunks via direct fiber etc.