Hello, I am afraid that with this generic question it’s difficult to help you. I would suggest that you start with a recent Kamailio version (e.g., 5.5.x) and have a look to the default configuration that comes with the package/source. There are already pre-defined switches for certain functionality (like registration) in it that you just need to enable. This should be a good starting point. If you are stuck at a certain position, just ask with more details on the list. If you are looking for somebody to help you commercially, there are several companies that offer support and/or training listed on kamailio.org. Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com<https://gilawa.com/> From: sr-users &lt;sr-users-bounces(a)lists.kamailio.org&gt; On Behalf Of Uwe Sigleur Sent: Monday, January 31, 2022 8:42 AM To: sr-users(a)lists.kamailio.org Subject: [SR-Users] two SIP proxies Dear Kamailia support, please could you help me. I need an Kamilia configuration (kamailia.cfg) for my SIP scenario. I have two Kamailia SIP proxies in my network. On the A side the subscribers (axx) are registered on SIP proxy SIP01 and on the B side the subscribers (bxx) are registered on SIP proxy SIP02. How must the kamailia.cfg looks like, that the A side INVITE etc. is routed to the B side and the REGISTER remains on the A side? Thanks in advance Uwe