vicidial.org

We have three dialers that are all connected (via IAX) to a regular asterisk machine that houses all our PRI circuits and VoIP connections, this machine is also accessed by our PBX and a few other VoIP appliances. We used to have the PRI circuits connected straight to the dialers and since we moved to this model we no longer get "DC" dispositions is there some programming on the basic asterisk box we need to configure to pass "DC" calls back to the dialers as disconnected numbers?

Yes, but the exact details of that is something of a challenge for most companies. It also gets expensive if you get someone who has never done exactly what you are asking before.

One method would be to use asteriskcdrdb on the PRI box to capture the "invalid" numbers and use a script to enter this data into the Vicidial database on a timed basis.

A more proper (and involved) method would utilize proper signalling from asterisk -> asterisk regarding disconnected numbers on IAX2 via the Reason Code.

I DO know that The Vicidial Group is qualified to perform this task, as evidence suggests that they have done so several times.