Macro to test phone lines

My CEO wants the ability to dial a number and then have the phone system automatically call all our external lines to make sure they are ringing through properly.

The way I am thinking is creating a feature code and just have one line dial all the others but I don’t necessarily want the phones to ring I just want the info that the lines are actually working and they would have rang if it was a real caller.

Anyway that any of you can think of accomplishing this?