<div dir="ltr"><div>I have just install OpenSIPs 1.11.x on Public network and server running on Public IP but somehow i am not able to register SIP client behind NAT (dynamic NAT  one to many). <br><br></div>I am successfully able to register without NAT sip client. following is my config<br>
<br><br># ----- Determining if client is behind NAT -----#<br>loadmodule &quot;nathelper.so&quot;<br>modparam(&quot;nathelper&quot;,&quot;natping_interval&quot;, 0)<br>modparam(&quot;nathelper&quot;,&quot;received_avp&quot;, &quot;$avp(i:42)&quot;)<br>
modparam(&quot;registrar&quot;,&quot;received_avp&quot;, &quot;$avp(i:42)&quot;)<br><br><br><br><br># Detect NAT<br>        force_rport();<br>        if (nat_uac_test(&quot;19&quot;)) {<br>                if (is_method(&quot;REGISTER&quot;) &amp;&amp; !is_present_hf(&quot;Record-Route&quot;)) {<br>
                fix_nated_register();<br>                }<br>        else {<br>                fix_nated_contact();<br>                }<br>                setflag(5);<br>        }<br><br>...<br>...<br><br> if (is_method(&quot;REGISTER&quot;))<br>
        {<br>                 if (isflagset(5)) {<br>                        setbflag(6);<br>                        setbflag(7);<br>                };<br><br> if (!save(&quot;location&quot;))<br>                        sl_reply_error();<br>
<br>                exit;<br>        }<br><br></div>