[asterisk-users] Drop Call on ICMP Port Unreachable?

[John Todd]

The idea of using ICMP unreachables as a method to shut down RTP  
streams (and corresponding signaling sessions) is a good one, and I'd  
like to see discussion on it.

There is the rtptimeout option in sip.conf which will possibly solve  
some of those symptoms (and has dangerous side-effects, when clients  
don't send CNG and are "on hold") but of course it is not the same  
mechanism and using ICMP unreachables is a better solution.

For those about to suggest it, the SIP session timers don't solve this  
problem in many cases, since signaling and RTP go to different places  
and ICMP unreachable on RTP doesn't imply that the signaling will also  
fail.

JT



On Oct 7, 2009, at 7:05 PM, Dan Mahoney, System Admin wrote:

> One of our users recently had a powerfail while connected to our  
> meetme
> gateway.  (Asterisk 1.4.17 on debian 4.0)
>
> Through the course of it, asterisk never hung up.  His system came  
> back
> up, and started sending ICMP port unreachables, but the stream went  
> on,
> flooding him with "silence" media stream packets (there was nobody  
> else in
> the conference).
>
> Is asterisk aware of ICMP unreachables?  Is there a tunable I can  
> set to
> make it be?
>
> I found a thread here that discusses it briefly:
>
> http://lists.digium.com/pipermail/asterisk-users/2005-March/ 
> 086626.html
>
> However, there's no real resolution there.
>
> If it's not aware of it, how difficult would it be to add?
>
> -Dan Mahoney
>
> -- 
>
> --------Dan Mahoney--------
> Techie,  Sysadmin,  WebGeek
> Gushi on efnet/undernet IRC
> ICQ: 13735144   AIM: LarpGM
> Site:  http://www.gushi.org
> ---------------------------

---
John Todd                       email:jtodd at digium.com
Digium, Inc. | Asterisk Open Source Community Director
445 Jan Davis Drive NW -  Huntsville AL 35806  -   USA
direct: +1-256-428-6083         http://www.digium.com/