[Asterisk-Users] SIP device rings once on busy before giving busy tone with dialplan

[Linus Surguy]

> My dialplan is for the outgoing SIP call is:
>
> exten => _00.,1,AbsoluteTimeout(3600)
> exten => _00.,2,Dial(${TRUNK1}/${EXTEN:2},45,r)
> exten => _00.,3,Answer
> exten => _00.,4,Hangup
> exten => _00.,103,Dial(${TRUNK2}/${EXTEN:2},45,r)
> exten => _00.,104,Answer
> exten => _00.,105,Hangup
>

I can't help with presenting busy to the SIP devices, but if you have the
above on any sort of PSTN gateway you are going to annoy the PSTN users - as
if the number selected is busy or otherwise unavailable you will still
'Answer' the PSTN call, causing the person calling to pay whatever call
establishment charges/minimum charges appropriate to their tariff.

Linus