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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Thank you Walter for your reply.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Unfortunately there is no way to change Carrier’s configuration so we need to find a way to tackle the issue on our side.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks again.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Regards<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b>From:</b> Walter Schober <walter.schober@neotel.at> <br><b>Sent:</b> Δευτέρα, 23 Ιουνίου 2025 10:37<br><b>To:</b> OpenSIPS users mailling list <users@lists.opensips.org><br><b>Cc:</b> apsaras@microbase.gr<br><b>Subject:</b> AW: [OpenSIPS-Users] Registrant & LB with SRV<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=DE-AT>Hello Antonis!<o:p></o:p></span></p><p class=MsoNormal><span lang=DE-AT><o:p> </o:p></span></p><p class=MsoNormal>IMHO the carrier cannot expect Register and Invite going to the same destination if the SRV for _<i>the</i>_ service is load-balanced.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>We do offer such a service as carrier also but encountered the issue with LB on nearly every device, incl. phones. Since we also need the call to be established across the same service endpoint selected in the Register process we set priorities on each SRV for each datacenter.<o:p></o:p></p><p class=MsoNormal>For such cases we do additionally name two A records where the endpoint must register on both and then can do LB calls to each. Otherwise the carriers service must allow registers and invites going different ways. It is **one** service based on the SRV entry!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Br<o:p></o:p></p><p class=MsoNormal>Walter<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=DE>Von:</span></b><span lang=DE> Users <<a href="mailto:users-bounces@lists.opensips.org">users-bounces@lists.opensips.org</a>> <b>Im Auftrag von </b>Antonios Psaras<br><b>Gesendet:</b> Freitag, 20. Juni 2025 11:24<br><b>An:</b> 'OpenSIPS users mailling list' <<a href="mailto:users@lists.opensips.org">users@lists.opensips.org</a>><br><b>Betreff:</b> [OpenSIPS-Users] Registrant & LB with SRV<o:p></o:p></span></p></div></div><p class=MsoNormal><span lang=DE-AT><o:p> </o:p></span></p><p class=MsoNormal>Hello Team<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have the following situation.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>A telecom carrier requires SIP Registration prior to Dial out using SIP Domain and SRV Lookup.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>To achieve that I am using registrant module and load balancing module.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The problem I have, is that in some cases registrant registers on different SBC of the Carrier than the one resolved by Load Balancer Module so my outbound calls are failing with 407.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have two thoughts but I do not know how to implement any of those.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><ol style='margin-top:0cm' start=1 type=1><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo3'>Instead of using LB Modules, I will some how get the registrar IP from registrant module and statically route the calls through that. Is there a way to get that information from registrant module?<o:p></o:p></li><li class=MsoListParagraph style='margin-left:0cm;mso-list:l0 level1 lfo3'>DNS lookup is done automatically only in case of 503 or timeout. Is there a way to force DNS lookup with in OpenSIP Script? If yes I can handle 407, force DNS Lookup, create a new branch and re-send the call.<o:p></o:p></li></ol><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Any other thoughts are welcome<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Best regards<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Antonis Psaras<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>