[asterisk-users] Ideas for call back when all lines are busy

[Sherwood McGowan]

Darrick Hartman (lists) wrote:
> Does anyone have an example of how to solve the following problem?
>
> Person has 3 analog lines.  The way I have the dial plan right now, if 
> all lines are busy and someone attempts an outbound call, they get 
> congestion. (something like this)
>
> exten => _1NXXNXXXXXX,1,Dial(${POTS}/${EXTEN},90)
> exten => _1NXXNXXXXXX,n,Congestion(5)
> ; POTS=Zap/G1
>
> What I'd like to do is if the line is busy, a that person receives a 
> call-back when a line becomes available.  Is this even possible?
>
> Thanks,
>
> Darrick
>   
Yes, check out ChanIsAvail()