[Asterisk-Users] RE: Multiple IAX clients behind a firewall

[Tim Panton]

On 13 Mar 2006, at 11:50, Adrian Carter wrote:

> Thanks all for advice... I have IAX clients configured pretty  
> standard, and they work fine connecting to the asterisk server if  
> coming via the itnernet.. but the moment I have more than one  
> attempted client from a remote office that gets NAT'ed into the  
> 'main' network so to speak it doesnt work. I only see one client  
> connect and "iax2 show peers" reflects only one client from that IP  
> and its connected on 4569. Subsequent clients attempting to connect  
> behind the NAT router get 'connection timedout' when trying to  
> register. If I unregister the first client, a new one can register,  
> but the same symptoms persist (the guy I unregistered can't re- 
> register again ...)
>
> Its a Dlink DI714P+ router in a completly vanilla out-of-the-box  
> setup - so if IAX 'just works' - what am I missing?? :)

I'd guess that the router is in a 'preserve source-port' mode, my  
NAT'd IAX connections look like this

a       192.67.4.80     (D)  255.255.255.255  1720          Unmonitored
b        82.163.107.203  (D)  255.255.255.255  21398         Unmonitored
l         82.163.107.203  (D)  255.255.255.255  23020          
Unmonitored
z        212.158.206.61  (D)  255.255.255.255  56598         Unmonitored

Note the middle 2 are from the same address but have different port  
numbers.

Tim

Tim Panton
tim at mexuar.com