[Asterisk-Users] Asterisk connecting to a proprietry PBX

[Gonzalo Servat]

Hi guys,

I'm interconnecting an Asterisk box with a Lucent Definity PBX by
means of FXO/FXS ports on a TDM2400 card. Everything works well,
except for one little thing. Every now and then somebody (from an
Asterisk extension) will call another extension on the Lucent Definity
PBX and they hit their voicemail. They caller leaves their message (or
not) and hangup, BUT the Lucent sometimes doesn't detect the hangup
and the channel never gets dropped. The call goes on and on and on (I
often have calls hanged for 20 hours or more). The problem is that
with the limited FXO/FXS ports we have, I often have people complain
they can't dial somebody, but it's simply because there are hanged
channels.

I did a ChanSpy on the hanged channels and all there is is dead
silence. I guess Asterisk is not going to drop the channel until it
hears the busy pattern, which I guess makes sense as you wouldn't want
to be hanged up on if there is any silence (obviously).  I was
wondering if there is some way I can configure Asterisk to hang up
calls if there is more than X minutes silence in a channel. For now, I
think the quick (and dirty, and not very nice) solution is to set an
AbsoluteTimeout of 1 hour on the calls, as 95% of calls are less than
one hour and will ensure there are no hanged chans longer than 1 hour
in the system.

Another idea I had in mind is to, maybe, set the voicemail system
(Audix) to cut messages after X minutes. I don't know for sure if the
(Asterisk) caller is leaving a message or not, as most voicemail
systems have a message size limit and drop the call anyway. Strange,
huh?

Any suggestions? opinions? sympathizing words? :-)

Thanks in advance guys.

Cheers,
Gonzalo