[Asterisk-Users] Re: Received VNAK: resending outstanding frames?

[Tim Panton]

On 11 Apr 2006, at 14:52, Carey O'Shea wrote:

> Some more info:
>
> Just tried this on a server without using any NAT and no port
> forwarding, no masquerading, and I still have the same problem. So  
> there
> goes that idea. I do not know what this VNAK error means.
>
> By the way, I am using the latest version (1.2.6) of asterisk, have  
> also
> tried other versions with the same problem [1.0.9 (Ubuntu Breezy) and
> 1.0.7 (Debian Sarge) and 1.2.1 (Ubuntu Dapper)].
>
> Wonder if this is something simple or not?
>
> On Tue, 2006-04-11 at 23:00 +1000, Carey O'Shea wrote:
>> I only receive 4 google results on my error. So some help would be
>> appreciated. I could not even determine what "VNAK" was.
>>
>> Let me describe my problem. I have an IAX hardware phone here that
>> connects and operates fine within my internal network. However,  
>> outside
>> my internal network, the hardware phone fails to register.
>>
>> The plot thickens: outside my internal network I've tested  
>> numerous IAX
>> softphones and strangely enough they function fine, where the  
>> hardware
>> phone does not.
>>
>> Of course (seeing as how the softphones work externally) I have  
>> both TCP
>> and UDP 4569 port forwarded to Asterisk server and there is no  
>> firewall
>> on the Asterisk server.
>>
>> So I am guessing there is some NAT issue or some configuration issue
>> with this hardware IAX phone I have.
>>
>> Below are the messages I receieve in my "full" log (about 20 or 30 of
>> them each second for many seconds, then after the flood of  
>> messages it
>> reports "Raw Hangup", and then soon enough it starts again).
>>
>> I'm using a "PA1686" IAX hardware phone.


I have a few PA1686 phones doing IAX through firewalls and NAT, so it  
is possible :-)

Try running :

iax2 debug

Can you send us the few lines in the log before the VNAK's start?

By the way, here is what the draft RFC says for VNAK

6.7.3.  VNAK

    A VNAK is sent when a message is received out of order, particularly
    when a mini frame is received before the first full voice frame on a
    call.  It is a request for retransmission of dropped messages.  A
    message is considered out of sequence if the received iseqno is
    different than the expected iseqno.  On receipt of a VNAK, a peer
    MUST retransmit all frames with a higher sequence number than the
    VNAK message's iseqno.



Tim Panton
tim at mexuar.com