Hi Fernando,
You should try to enable ICE. In your configuration it's currently disabled (ICE=remove) With this parameter enabled SDP should offer multiple options to contact. The problem you have is not related to NAT because you can send and receive SIP messages between your client and server. The problem is that your SDP only indicates private IP, and your client and server are not in the same private network.
Hope it helps
-----Mensaje original----- De: Fernando Lopes via sr-users sr-users@lists.kamailio.org Enviado el: domingo, 13 de abril de 2025 18:06 Para: sr-users@lists.kamailio.org CC: Fernando Lopes fernandolopes20003@gmail.com Asunto: [SR-Users] Nat Problems Kamailio
Hello Everyone, I'm having some trouble getting my SIP setup to work properly.
📞 My Call Flow: SIP Client initiates a call The call reaches my router, which forwards it to Kamailio + RTPengine running on 192.168.1.75:5060, which then forwards it to A Kubernetes machine at 192.168.1.190:32210, where Asterisk is running
🔧 Network Setup: Router has the following ports forwarded: UDP 5060 UDP 10000–20000 (for RTP) STUN is enabled on the SIP client
✅ What Works: When I’m connected through a VPN (i.e., inside the local network), everything works fine — both incoming and outgoing audio.
❌ The Problem: When calling from outside the network, signaling works and the call connects, but I can’t receive or send any audio.
Here is a little of my config of kamailio modparam("rtpengine", "rtpengine_sock", "udp:127.0.0.1:2223") modparam("rtpengine", "setid_avp", "$avp(setid)") listen=udp:192.168.1.75:5060 advertise https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f62.2x.xxx.xxx%3a5060&... listen=tcp:192.168.1.75:5060 advertise https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f62.2x.xxx.xxx%3a5060&... listen=udp:127.0.0.1:5060 #Nat Helper modparam("nathelper", "force_socket", "192.168.1.75:5060") modparam("nathelper", "natping_interval", 10) modparam("nathelper", "ping_nated_only", 0) modparam("nathelper", "nat_addr_mode", 1)
request_route{ ... route(init); ... if(is_method("INVITE|ACK|BYE|CANCEL|OPTIONS|INFO|UPDATE|PRACK")){ route(handle_sip); exit; } } route[init]{ ... if (nat_uac_test("19")){ setflag(FLT_NAT); fix_nated_contact(); force_rport(); } } route[handle_sip]{ if ($rm == "INVITE"){ if (isflagset(FLT_NAT)){ route(natmanage); }
if (!ds_select_dst("1", "4")){ sl_send_reply("500", "No destination"); exit; }
$ru = "sip:" + $rU + "@" + $rd; # Keeps sip:100@domain $du = "sip:192.168.1.190:32210"; # Matches your dispatcher list
route(relay); }
if ($rm == "BYE" || $rm == "CANCEL"){ if (isflagset(FLT_NAT)){ rtpengine_delete(); }
route(relay); }
if ($rm == "ACK"){ if (isflagset(FLT_NAT)){ route(natmanage); }
route(relay); } route(relay); } route[natmanage]{ if (is_request()){ if (has_body("application/sdp")){ rtpengine_offer("replace-origin replace-session-connection ICE=remove"); } force_rport(); fix_nated_contact(); }else{ rtpengine_answer("replace-origin replace-session-connection ICE=remove"); } } rtpengine.conf
[rtpengine] table = 0 interface = internal/192.168.1.75 listen-ng = 127.0.0.1:2223 log-level = 7
timeout = 60 silent-timeout = 3600 tos = 184
port-min = 10000 port-max = 40000
And here are some logs when I call from outside
2025/04/13 15:58:33.407265 https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f2.8x.xx.xxx%3a59396&... -> 192.168.1.75:5060 INVITE sip:100@192.168.1.75:5060 SIP/2.0 Via: SIP/2.0/UDP 192.168.1.116:59396;rport;branch=z9hG4bKPj92490d6b6d0c4cd88dac9f0043b1642e Max-Forwards: 70 From: "6001" sip:6005@192.168.1.75:5060;tag=0397d2bdc3ef47f5b6e498126a360b0f To: sip:100@192.168.1.75:5060 Contact: "6001" sip:6005@192.168.1.116:59396;ob;+https://linkprotect.cudasvc.com/url?a=https%3a%2f%2fsip.ice&c=E,1,bmYYCS... Call-ID: 83a804569c3f489088607c729485cdbd CSeq: 8963 INVITE Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS Supported: replaces, 100rel, timer, norefersub Session-Expires: 1800 Min-SE: 90 User-Agent: MicroSIP/3.21.5 Content-Type: application/sdp Content-Length: 537
v=0 o=- 3953552313 3953552313 IN IP4 192.168.1.116 s=pjmedia b=AS:84 t=0 0 a=X-nat:0 m=audio 4032 RTP/AVP 8 0 101 c=IN IP4 192.168.1.116 b=TIAS:64000 a=rtcp:4017 IN IP4 192.168.1.116 a=sendrecv a=rtpmap:8 PCMA/8000 a=rtpmap:0 PCMU/8000 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-16 a=ssrc:1567952351 cname:73284f1717045a81 a=ice-ufrag:37e51dc0 a=ice-pwd:49f7442b5078148140877b44 a=candidate:Hc0a80174 1 UDP 2130706431 192.168.1.116 4032 typ host a=candidate:Hc0a80174 2 UDP 2130706430 192.168.1.116 4017 typ host
2025/04/13 15:58:33.412683 192.168.1.75:5060 -> 192.168.1.190:32210 INVITE sip:100@192.168.1.75 SIP/2.0 Via: SIP/2.0/UDP https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f62.2x.2xx.xxx%3a5060&... Via: SIP/2.0/UDP 192.168.1.116:59396;received=https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f2.8x.xx.xxx&c=E,1,IZ... Max-Forwards: 69 From: "6001" sip:6005@192.168.1.75:5060;tag=0397d2bdc3ef47f5b6e498126a360b0f To: sip:100@192.168.1.75:5060 Contact: "6001" sip:6005@2.8x.xx.xxx:59396;ob;+https://linkprotect.cudasvc.com/url?a=https%3a%2f%2fsip.ice&c=E,1,ZknIye... Call-ID: 83a804569c3f489088607c729485cdbd CSeq: 8963 INVITE Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS Supported: replaces, 100rel, timer, norefersub Session-Expires: 1800 Min-SE: 90 User-Agent: MicroSIP/3.21.5 Content-Type: application/sdp Content-Length: 322
v=0 o=- 3953552313 3953552313 IN IP4 192.168.1.75 s=pjmedia b=AS:84 t=0 0 a=X-nat:0 m=audio 12156 RTP/AVP 8 0 101 c=IN IP4 192.168.1.75 b=TIAS:64000 a=ssrc:1567952351 cname:73284f1717045a81 a=rtpmap:8 PCMA/8000 a=rtpmap:0 PCMU/8000 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-16 a=sendrecv a=rtcp:12157
2025/04/13 15:58:33.428169 https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f2.8x.xx.xxx%3a59396&... -> 192.168.1.75:5060 INVITE sip:100@192.168.1.75:5060 SIP/2.0 Via: SIP/2.0/UDP 192.168.1.116:59396;rport;branch=z9hG4bKPj14c6f24b814e4d158014cc80b1fa5f8f Max-Forwards: 70 From: "6001" sip:6005@192.168.1.75:5060;tag=0397d2bdc3ef47f5b6e498126a360b0f To: sip:100@192.168.1.75:5060 Contact: "6001" sip:6005@192.168.1.116:59396;ob;+https://linkprotect.cudasvc.com/url?a=https%3a%2f%2fsip.ice&c=E,1,WEwhdR... Call-ID: 83a804569c3f489088607c729485cdbd CSeq: 8964 INVITE Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS Supported: replaces, 100rel, timer, norefersub Session-Expires: 1800 Min-SE: 90 User-Agent: MicroSIP/3.21.5 Authorization: Digest username="6005", realm="asterisk", nonce="1744559913/dab8894e3f31e038d7a969a6349a11c2", uri="sip:100@62.2x.2xx.xxx", response="2ce500d6a1583f05f6344bdf1f712fc7", algorithm=MD5, cnonce="808fc766135d40589dd68032bcaab5c6", opaque="2232aa9c42080f12", qop=auth, nc=00000001 Content-Type: application/sdp Content-Length: 537
v=0 o=- 3953552313 3953552313 IN IP4 192.168.1.116 s=pjmedia b=AS:84 t=0 0 a=X-nat:0 m=audio 4032 RTP/AVP 8 0 101 c=IN IP4 192.168.1.116 b=TIAS:64000 a=rtcp:4017 IN IP4 192.168.1.116 a=sendrecv a=rtpmap:8 PCMA/8000 a=rtpmap:0 PCMU/8000 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-16 a=ssrc:1567952351 cname:73284f1717045a81 a=ice-ufrag:37e51dc0 a=ice-pwd:49f7442b5078148140877b44 a=candidate:Hc0a80174 1 UDP 2130706431 192.168.1.116 4032 typ host a=candidate:Hc0a80174 2 UDP 2130706430 192.168.1.116 4017 typ host
2025/04/13 15:58:33.430593 192.168.1.75:5060 -> https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f2.8x.xx.xxx%3a59396&... SIP/2.0 100 trying -- your call is important to us Via: SIP/2.0/UDP 192.168.1.116:59396;rport=59396;branch=z9hG4bKPj14c6f24b814e4d158014cc80b1fa5f8f;received=https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f2.8x.xx.xxx&c=E,1,QX... From: "6001" sip:6005@192.168.1.75:5060;tag=0397d2bdc3ef47f5b6e498126a360b0f To: sip:100@192.168.1.75:5060 Call-ID: 83a804569c3f489088607c729485cdbd CSeq: 8964 INVITE Server: kamailio (5.7.4 (x86_64/linux)) Content-Length: 0
2025/04/13 15:58:33.461894 192.168.1.75:5060 -> 192.168.1.190:32210 INVITE sip:100@192.168.1.75 SIP/2.0 Via: SIP/2.0/UDP https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f62.2x.2xx.xxx%3a5060&... Via: SIP/2.0/UDP 192.168.1.116:59396;received=https://linkprotect.cudasvc.com/url?a=https%3a%2f%2f2.8x.xx.xxx&c=E,1,PQ... Max-Forwards: 69 From: "6001" sip:6005@192.168.1.75:5060;tag=0397d2bdc3ef47f5b6e498126a360b0f To: sip:100@192.168.1.75:5060 Contact: "6001" sip:6005@2.8x.xx.xxx:59396;ob;+https://linkprotect.cudasvc.com/url?a=https%3a%2f%2fsip.ice&c=E,1,_Y0zCc... Call-ID: 83a804569c3f489088607c729485cdbd CSeq: 8964 INVITE Allow: PRACK, INVITE, ACK, BYE, CANCEL, UPDATE, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE, OPTIONS Supported: replaces, 100rel, timer, norefersub Session-Expires: 1800 Min-SE: 90 User-Agent: MicroSIP/3.21.5 Authorization: Digest username="6005", realm="asterisk", nonce="1744559913/dab8894e3f31e038d7a969a6349a11c2", uri="sip:100@62.2x.2xx.xxx", response="2ce500d6a1583f05f6344bdf1f712fc7", algorithm=MD5, cnonce="808fc766135d40589dd68032bcaab5c6", opaque="2232aa9c42080f12", qop=auth, nc=00000001 Content-Type: application/sdp Content-Length: 322
v=0 o=- 3953552313 3953552313 IN IP4 192.168.1.75 s=pjmedia b=AS:84 t=0 0 a=X-nat:0 m=audio 12156 RTP/AVP 8 0 101 c=IN IP4 192.168.1.75 b=TIAS:64000 a=ssrc:1567952351 cname:73284f1717045a81 a=rtpmap:8 PCMA/8000 a=rtpmap:0 PCMU/8000 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-16 a=sendrecv a=rtcp:12157
Please Help me, Thank you. __________________________________________________________ Kamailio - Users Mailing List - Non Commercial Discussions -- sr-users@lists.kamailio.org To unsubscribe send an email to sr-users-leave@lists.kamailio.org Important: keep the mailing list in the recipients, do not reply only to the sender!