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<tt>So far, yes. But to be 100% you need to check via a pcap the fragmentation
flags in the IP packet(s) for the SIP INVITE. This will tell you
(1) if the packet is fragmented and (2) if all the IP packets (UDP
fragments) are present.<br>
<br>
Regards,<br>
</tt>
<pre class="moz-signature" cols="72">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a class="moz-txt-link-freetext" href="http://www.opensips-solutions.com">http://www.opensips-solutions.com</a></pre>
<div class="moz-cite-prefix">On 17.05.2016 20:07, Nabeel wrote:<br>
</div>
<blockquote
cite="mid:CA+vx6KKrtfvHmxjMVjAwZvAtZRFzx0hNKE-kBXPqO9JaED6r-w@mail.gmail.com"
type="cite">
<p dir="ltr">In that case, the answer to your question seems to be
that the UDP packets did not reach the OpenSIPS server, because
nothing was added to the OpenSIPS logs using debug level 4. All
of this seems to point to the cause being UDP packet
fragmentation. Is this correct? </p>
<div class="gmail_quote">On 17 May 2016 4:24 pm, "Bogdan-Andrei
Iancu" <<a moz-do-not-send="true"
href="mailto:bogdan@opensips.org">bogdan@opensips.org</a>>
wrote:<br type="attribution">
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF"> <tt>The TCP/IP stack
of your server may decide to drop an UDP packet if it
cannot re-assemble it correctly (like not all the IP
fragments were received).<br>
In such a case, you see the IP packets (carrying the
fragments) on network level, but they are never delivered
at application level.<br>
<br>
Regards,<br>
</tt>
<pre cols="72">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a moz-do-not-send="true" href="http://www.opensips-solutions.com" target="_blank">http://www.opensips-solutions.com</a></pre>
<div>On 17.05.2016 16:05, Nabeel wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<blockquote class="gmail_quote" style="margin:0px 0px
0px
0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">The
next question - is this INVITE reaching your opensips
script ? to be sure that the OS delivers the UDP
packet to the opensips application.</blockquote>
<div><br>
</div>
<div>I don't have any firewall on my server. Why would
the UDP packet get blocked between entering the server
and reaching opensips script? The opensips server is
running without errors. Other calls work fine.</div>
</div>
</blockquote>
<br>
</div>
</blockquote>
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</blockquote>
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