nathelper OPTIONS ping - sr-users

25 Mar 2022


      Hello all,
I am trying to periodically send SIP OPTIONS to all connected WebRTC clients from Kamailio. The functionality is similar to qualify=yes of Asterisk. Following are the configuration changes I have made to get this working.
#!define FLB_NATSIPPING 7
<snip/>
loadmodule "nathelper.so"
<snip/>
# ----- nathelper params -----
modparam("nathelper|registrar", "received_avp", "$avp(RECEIVED)")
modparam("nathelper", "sipping_bflag", FLB_NATSIPPING)
modparam("nathelper", "natping_interval", 20)
modparam("nathelper", "sipping_from", "sip:pinger@kamailio.org")
<snip/>
# Handle SIP registrations
route[REGISTRAR] {
        if (is_method("REGISTER")) {
                xlog("L_INFO", "Processing REGISTER in route[REGISTRAR]\n");
if(isflagset(FLT_NATS)) {
                        setbflag(FLB_NATB);
                        # do SIP NAT pinging
                        xlog("L_INFO", "Setting FLB_NATSIPPING\n");
                        setbflag(FLB_NATSIPPING);
                }
if (!save("location")) {
                        sl_reply_error();
                }
                xlog("L_INFO", "Successfully processed REGISTER in route[REGISTRAR]\n");
                exit;
        }
}
When the WebRTC client registers, I can see the log: Setting FLB_NATSIPPING, but SIP OPTIONS packets are not seen. I am checking it  using the Chrome console, at client side  as well as sipdump module in server side.
Do I have to do any additional configuration? I am not posting the full config file here so that its easy to focus on the relevant parts, but can do that if needed.
Thanks and regards,
X.