<div dir="ltr"><div>You mean like this, right?</div><div><br></div><div>if (is_method("REGISTER"))</div><div><br></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>{</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>if ( 0 ) setflag(TCP_PERSISTENT);</div><div><br></div><div> <span style="font-family:arial,helvetica,sans-serif">setbflag(SIP_PING_FLAG);</span></div><div><br></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>if (!save("location"))</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>sl_reply_error();</div><div><br></div><div><span class="Apple-tab-span" style="white-space:pre"> </span>exit;</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>}</div><div><br></div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On 7 August 2015 at 17:52, Bogdan-Andrei Iancu <span dir="ltr"><<a href="mailto:bogdan@opensips.org" target="_blank">bogdan@opensips.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
Hi Nabeel,<span class=""><br>
<pre cols="72">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a href="http://www.opensips-solutions.com" target="_blank">http://www.opensips-solutions.com</a></pre>
</span><div>On 07.08.2015 19:39, Nabeel wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr"><font face="arial, helvetica, sans-serif">[........]</font><span class=""><br>
<div><font face="arial, helvetica, sans-serif">Bogdan,</font></div>
<div><font face="arial, helvetica, sans-serif"><br>
</font></div>
<div><font face="arial, helvetica, sans-serif">Regarding UDP, I
realised that the UDP port could not be in LISTEN state and
this was probably preventing my server from fully opening
that port. Running nmap on that port showed result
"open|filtered", unlike with TCP which showed fully open. I
am not running any firewalls on my server, so this seems to
be the default behaviour of my network.</font></div>
</span></div>
</blockquote>
<font face="arial, helvetica, sans-serif">A bidirectional traffic
through the NAT will keep the NAT pinhole open, while a
unidirectional one may not. This is the advantage of the SIP
pinging versus simple UDP pinging.</font><span class=""><br>
<blockquote type="cite">
<div dir="ltr">
<div><font face="arial, helvetica, sans-serif"><br>
</font></div>
<div><span style="font-family:arial,helvetica,sans-serif">I
would like to clarify one thing. You mentioned adding
setbflag(SIP_PING_FLAG) before doing save(), but in my
config file I don't see save() anywhere, there is only this
line: "if (!save("location"))". Where exactly do I add this
line?</span><font face="arial, helvetica, sans-serif"><br>
</font></div>
</div>
</blockquote>
</span><font face="arial, helvetica, sans-serif">exactly.</font><br>
<br>
<font face="arial, helvetica, sans-serif">Regards,<br>
Bogdan<br>
</font><br>
</div>
</blockquote></div><br></div>