[TriLUG] Asterisk calls dropping after a few minutes

[Matt Pusateri]

What is the firewall in front of it?  Does it have ALG voice helper 
stuff available and turned on?  Usually when you see voip calls drop 
after a specific time, it's firewall related.  I have a hard time 
believing blowing into the mic is really doing anything.  I would more 
likely suspect codec negotiation problems, that's delaying audio.

Codec issues you can see in the asterisk logs, you may have to turn 
debugging up. Make sure you don't leave it up as it can be verbose and 
fill up disk space fast.  Finally I would suggest tcpdumping the call.  
Wireshark does a really good job at being able to look at voice captures 
and you should be able to see a call flow within wireshark that would 
maybe show you where the call is terminating.  Depending on your 
firewall I tcpdump from the asterisk box and the firewall if possible.

Matt P.

On 08/04/2011 10:00 PM, Joseph S. Tate wrote:
> I've got a Cisco 7905 IP phone connected to Trixbox going out to a
> callwithus.com SIP gateway.  I can dial out ok*, but the call drops after
> about 2 minutes.  I've tried to follow the log on the Trixbox server, but
> all I can see is something is triggering a hangup event.  It's not the
> remote party, and the phone doesn't reboot, or show anything wrong.  Anyone
> have pointers to how I can troubleshoot this?
>
> * I say OK, but after dialing, the number, I can't hear the ring, or the
> remote party that's answered until I blow into the mic, or otherwise make
> some sort of sound on my end.
>