[asterisk-users] Cisco 7960 Double Natted

[Steve Totaro]

Barry Fawthrop wrote:
> Hi All
>
> Yes I know double Nat is a problem
>
> But I have a Cisco 7960 which is remote from the * PBX ad connected 
> via the Internet. Each side has NAT
>
> (1) Sometimes it will work often it won't. And when it decides to work 
> is random
>
> Always
> (2) The Register side works fine. SIP SHOW PEERS has the phone listed 
> with the correct IP address and an average Qualify time (121 ms)
>
> Always
> (3) You can make calls outbound with the Cisco phone through the * PBX
>
> Problem
> (4) You can not receive any calls (when not working correctly)
>     (a) The Phone rings but not voice goes through
>     (b) Sometimes get a 481 "Call Leg Does Not Exist"
>     (c) Sometimes get a  -- is circuit-busy
>
> (5) On a reload of the * box you will 95 % sure loose the connection 
> if it was working ?
>
> (6)  SIP 5060  - 5063  and RTP 10000 - 25000 is open and port 
> forwarded on both sides
>
> (7) All calls are VoIP and terminate or originate via a VoIP Provider
>
> Anybody got any ideas, I have tried everything
>
> Thanks All
> Barry
>
You could try giving up and not wasting anymore time.  At least that was 
my experience after spending MANY hours working on a solution. 

Well I came up with a solution, and it was to remove the double NAT, at 
least to layer 3 of the stack.  OpenVPN saved the day.

Thanks,
Steve Totaro