We are having a lot of trouble with the Centrex dialing with our FreePBX. The Centrex solution supports 4 digit dialing as well as 10 digit dialing and requires a 9.
We have a lot of problems where when dialing out, the line says wrong number, or number invalid.
I have the trunks set to route 9XXXXXXXXXX to go to DADHI, but it’s returning that the line is busy or number invalid.
Technically you need to wait a little for the centrex dialtone after pressing 9. That can be done by adding D(9w) , more w’s if necessary they are 500ms each, to the dial options for the trunk, unfortunately that will break any centrex extension dialing you do, so you will have to make two “pseudo” dahdi trunks to suit XXXX and NXXNXXXXXX dial patterns. It is then your decision to require 9 before external calls or not by your users.
That’s a good point. I didn’t even think about it.
So my dial pattern would be?
9DWWNXXNXXXXXX
Pound Sign DWWXXXX
since we dial a pound to call station to station.
We have old analog phones so the only way to tell the lines apart with the hardware we have is to dial 9 to activate the DADHI line or 1 to activate the VOIP line.
Centrex equipment is very old, they don’t need relaxdtmf , because it always increases the possibility of “talk-off”, they expect humans (aka 2500 like sets and 1A2 racks locally) and not machines to do the dialing, the 80ms dtmf signal often outpaces old Nortel and AT&T switches in the US which are mostly used to provide Centrex service. My suggestions are to better duplicate such human behavior