I experienced a similar problem with kamailio and packet fragmentation on a Fedora 17 (32bit with its stock kernel) and kamailio 4.0.1:

Some mobile softphones(I think it was Zoiper or CSipSimple on Androids) were configured to negotiate a whole lot of codecs which made the invites have a huge sdp that made the packet too big. Normally OS should deal with it but the calls were not going through. I am sorry I dont have more details, I just told the user to use 2-3 codecs and problem was solved. Maybe kamailio has some kind of upper limit buffer equal to the MTU? I am not familiar with so low leveled details though.

Bill.

On Fri, Oct 25, 2013 at 9:58 AM, Daniel-Constantin Mierla <miconda@gmail.com> wrote:

Hello,

On 10/25/13 2:45 AM, Gus Monti wrote:

Hi,

There are often times where key packets are missing from homer traces. This seems to be caused by packet fragmentation. It is most readily evidenced by the trace showing an Invite entering the SBC from the outside and then no invite on the inside being seen but the 100 trying is seen on both sides.

Any Idea why?

can you look at the traffic on the network (e.g., with ngrep)? Maybe you haven't set the flag for storing the outgoing requests. Fragmentation is a matter of OS and if you run a recent Linux based distro, this should be no problem.

Cheers,
Daniel

-- Daniel-Constantin Mierla - http://www.asipto.com http://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda Kamailio Advanced Trainings - Berlin, Nov 25-28; Miami, Nov 18-20, 2013 - more details about Kamailio trainings at http://www.asipto.com -
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