[SR-Users] How to disable retransmits via TCP connection? etc.

[Daniel-Constantin Mierla]

On 23/06/15 19:06, Andrey Utkin wrote:
> 2015-06-23 18:49 GMT+03:00 Daniel-Constantin Mierla <miconda at gmail.com>:
>> Have you grabbed the sip trace on client side to see what it is
>> receiving? Are the clients reporting errors?
> Yes, see this https://gist.github.com/krieger-od/c9fe6ea4bb64fac82cda
> this is taken on Linux box running Jitsi desktop app.
> It doesn't report anything, or I haven't seen the log, ut just doesn't
> show the incoming call.

Jisti has options to enable logging -- search on the web how to enable
and where is located the log file.

It would be interesting to see if it receives any packet and prints any
error message there.

Have you tried with tls? That will rule out eventual packet mangling on
the way done by providers/routers ALGs.

Cheers,
Daniel
>
>
>> If you have a snom phone, you can easily see the received sip packets
>> via web interface. Perhaps the desktop phones will have also some logs
>> printing what is happening that can be accessed easily.
>>
>> Eventually you can try to run a kamailio locally, near the client, using
>> it as an intermediate proxy between the phone and the main sip server.
>>
>> The timestamps I checked in previous traces were not following the sip
>> retransmissions intervals (0.5sec, 1sec, 2sec, ...), a clear indication
>> that it is not kamailio transaction layer doing retransmissions.
>
>> As I said before, ngrep is not a source to trust when dealing with large
>> packets. Also, it can happen that it prints the same packet twice.
> But what sniffer should I try instead of ngrep to have more details
> and confidence?
>
> Also I guess you mean this to be an issue of Linux kernel on any side,
> or possibly of routing hardware somewhere in the route?
>

-- 
Daniel-Constantin Mierla
http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda
Book: SIP Routing With Kamailio - http://www.asipto.com