Ephone-DN Example

ephone-dn 1 dual-line
no call-waiting beep accept
number 2486
description K. Pasewaldt
name Pasewaldt, Kurt
call-forward noan 22486 timeout 15
huntstop channel
no huntstop

"no call-waiting beep" prevents the user from hearing a beep in the handdset when another call comes in. There is a new command called "call-waiting ring" which produces a short ring instead of a beep in the handset.

To forward calls to Asterisk voice mail I use the "call-forward noan" command. If no one picks up in 15 seconds, dial 22486 which is dial peer 400. Peer 400 points to the Asterisk server.

ephone-dn 2 dual-line
no call-waiting beep generate
number 2486
name Pasewaldt, Kurt
preference 1
call-forward busy 22486
call-forward noan 22486 timeout 15
huntstop channel

The only difference between ephone-dn 1 and 2 is the addition of "call-forward busy 22486" and "preference 1".

"preference 1" just tells what order to select the dn. "call-forward busy 22486" means if both ephone-dns are busy, forward the call to 22486 which is routed to Asterisk voice mail via dial peer 400.

If you were to remove "hunstop channel" command from both ephone-dns, you would be able to have four active calls on the 7940/60 phones before the "call-forward busy" command would take effect on the fifth incoming call.
The voice mail announcement on the Asterisk box is the same whether or not the CME forwarded the call using the "call-forward noan" or "call-forward busy" command. See extension.conf.