[Asterisk-Users] Failover: iconnecthere to voicepulse

[Rich Adamson]

> I'm working on a setup for a small office.  I'd like to use SIP/iconnecthere
> most of the time, because they're cheap.  But they only allow a single call. 
> When the single iconnecthere line is in use, I'd like to use IAX2/voicepulse
> instead:
> 
> exten => _1NXXNXXXXXX,1,Dial,SIP/BYEXTENSION at iconnect
> exten => _1NXXNXXXXXX,2,Dial,IAX2/npI42VoD38 at voicepulse/${EXTEN}
> 
> Well, it's not working because iconnecthere actually picks up the second call
> and plays a message.  So nothing ever gets to line 2 above.  I got quite
> excited when I saw the sip.conf option:
> 
> outgoinglimit=1
> 
> Which one might expect would prevent 2 concurrent calls on iconnect.  But that
> doesn't seem to have any effect.
> 
> So I've been wondering if there is another way.  I guess I could spawn a
> system command that goes and looks at the current SIP connections.  But that
> seems a bit desperate, not to mention prone to race conditions.
> 
> Any ideas?

Might check 'show application ChanIsAvail'. I don't have a need for it, so
don't know if it applies to sip channels for sure. Best guess is combining
outgoinglimit with ChanIsAvail and test it.

Second guess is the construction of the dialplan as shown above. 
If 1,Dial,SIP incurres a busy, what happens?