Auto-select available FXO TRUNK on Prefix dialing


Hi All!

We’re currently using a UCM6202 IP-PBX and have two FXO Lines on it. Is there a way to set it up where, with the press of a button (say, dial 0), it auto-selects which of these two lines is currently available? other vendors even gives one the option to do a “round robin” if both FXO lines are available at the time.

example: the user (who wishes to make outbound calls) dials 0, waits for a dial tone (as a signal that the pbx system has already selected an available FXO line, then dial the actual telephone number to make that call.

TL;DR - in order to make a call, one needs to dial a prefix code first (preferably “0”) and wait for the dial tone before dialing the phone number.

Appreciate your responses!



that is a simple prefix and strip a digit in outbound routes… nothing too exotic to have to achieve it.


@scottsip is correct - you can do this with prefixes on your routes and then strip the prefixes off before dialing. However, you will not get the dialtone you would in the old days. In other words, dialing 0, waiting for tone, then dialing 123456789 would be simply dialing 0123456789.


thanks SmartVox. and i am very2x grateful for THE VERY DETAILED ANSWER BY scotsip. very detailed and very professional!