You are using DMQ to replicate usrloc between registrars ? This should not affect the "proxy servers", although their exact role is not mentioned. If this is the case, you could do some kamcmd ul.dump on both registrars. Also the DMQ traffic can be traced by tcpdump etc. You may also want to validate the DMQ bus, "the way each node learns about the other ones." On Thu, Apr 25, 2024 at 10:46 AM satyaprakash ch via sr-users < sr-users(a)lists.kamailio.org&gt; wrote:

Hello, in case you like to synchronize between 5.5.x and 5.7.x with DMQ – this is not recommended and in fact also not supported. You need to stay in one major version within a DMQ cluster (e.g. only 5.5.x or 5.7.x). Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com<https://gilawa.com/> From: satyaprakash ch via sr-users &lt;sr-users(a)lists.kamailio.org&gt; Sent: Donnerstag, 25. April 2024 16:21 To: Kamailio (SER) - Users Mailing List &lt;sr-users(a)lists.kamailio.org&gt; Cc: satyaprakash ch &lt;chiramchetty.satyaprakash(a)gmail.com&gt; Subject: [SR-Users] Compatibility issue between proxy and registrar Hi, There are two proxy servers and two registrar servers with DMQ enabled, and we have upgraded the proxy servers to 5.7.4 and the registrar servers to 5.5.5. Kamailio proxy version 5.7.4 Kamailio registrar version: 5.5.5 Following the upgrade of the proxy server to 5.7.4, calls are not working and no response is received. Once again, we have reverted the proxy server to 5.5.5, so that the proxy server and the registrar server version are now the same.The calls are now working as expected. We suspect it could be an DMQ issue. I would appreciate your suggestions on this matter of compatibility between proxy and registry servers. Thanks.