FreePBX 12 – Configure a trunk

A trunk is our connection to the outside world. We use it to tell FreePBX about any call providers we use for inbound and outbound calls. You can set up as many trunks as you want.

Configuring a trunk with different providers will be similar but can vary in the exact settings used. If you’re unsure how to configure FreePBX with your provider ask them for information about configuring their service for use with Asterisk (and specifically FreePBX). If you still can’t get it to work open a support ticket and we’ll check it out.

Here I’m going to use the Localphone account we configured here

1 – Select Connectivity / Trunks from the main menu

FreePBX 12 add a trunk

2 – Specify that you will create a SIP trunk

FreePBX 12 add a SIP trunk

3 – Trunk details

Give your trunk a name

FreePBX 12 trunk name

Scroll down to outgoing settings. This is where you will enter the details provided by your ITSP. Exact details you need to provide will vary by provider, but here are some general tips …

  • You will normally want to enter the details under “Outgoing Settings” even if you are setting up an trunk for inbound calls (or inbound and outbound)
  • You will probably want “context=from-trunk” even if the provider says something different
  • The registration string at the bottom forces your system to register with the call provider, meaning they know where to send inbound calls
  • You will get a warning about outbound caller ID if you don’t set one. It’s not mandatory that you set one, but advised
  • Inbound calls can be tricky to get working, if you struggle then please open a support ticket
  • Don’t forget to Apply Settings after making any changes!

FreePBX trunk details outgoing settings

FreePBX 12 outbound caller ID warning

4 – Check if your trunk is registered … maybe!

If you entered registration details then you can check if Asterisk registered correctly. You might not need to enter registration details, if not you can skip this step.

Select Reports / Asterisk Info from the main menu

FreePBX 12 Reports Asterisk Info

Select registries on the right hand side of the page and you should see that your system has registered with the call provider

FreePBX 12 Registries