Connecting two Asterisk/FreePBX using SIP Trunks

This was a project that I’ve been working on and off for some time and always ended up with failure. There are many documentations available on the net however the one that worked for me is using IP trunks and here’s how it is done.

Lets take an example so it’s easy to identify. Let’s assume the the two PBXes are at Sydney & Melbourne.

In Sydney PABX, create a new trunk, name it to-Melbourne. For the peer details set it up as follows:

Trunk Name: melbPABX

type=friend
context=from-trunk
host=Melbourne-PABX-IP-OR-FQDN
username=sydPABX
password=superstrongsecretpassword
qualify=yes

In the Melbourne PABX, create a new trunk with a name to-Sydney. For the peer details set it up as follows:

Trunk Name: sydPABX

type=friend
context=from-trunk
host=Sydney-PABX-IP-OR-FQDN
username=melbPABX
password=superstrongsecretpassword
qualify=yes

Points to remember:

  • Password common for both trunks.
  • Trunk names used under Peer Details acts as the usernames.
  • Extension numbers should differ on each PABX otherwise it would not be possible to route calls correctly.