Hello all we are seeing these kind of logs in a Debian GNU/Linux 11 using kamailio 5.5.6 Sep 21 17:41:13 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155702]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:164.152.22.248:5060) Sep 21 17:41:13 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155698]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:208.74.138.184:5060) Sep 21 17:41:13 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155695]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:208.74.138.181:5060) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155693]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:38.102.250.60:5060) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155707]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:87.1.1.27:5060) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155707]: ERROR: tm [ut.h:302]: uri2dst2(): no corresponding socket for "87.1.1.27" af 2 Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155707]: ERROR: tm [t_fwd.c:470]: prepare_new_uac(): can't fwd to af 2, proto 1 (no corresponding listening socket) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155697]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:208.74.138.184:5060) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155694]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:192.40.216.97:5060) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155694]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:208.74.138.180:5060) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155714]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:87.1.1.27:5060) The kamailio instance we are using is receiving around 1500 calls per second in average when we do start seeing these errors more frequently In this instance we are using multihomed the listen address list is children=14 socket_workers=1 listen=udp:192.168.99.70:5081 listen=udp:192.168.99.81:5060 listen=udp:87.1.1.27:5060 listen=tcp:192.168.96.105:8095 listen=tcp:87.1.1.27:5060 tcp_children=6 port=5060 We use the first worker only to perform the OPTIONS requests from the dispatcher module. The sockets listen=udp:192.168.99.81:5060 listen=udp:87.1.1.27:5060 are used to communicate both A and B legs so when a message is received at 192.168.99.81:5060 we send it to 87.1.1.27:5060 and viceversa We were using $fs variable before doing the t_relay() function. This way is working, but when load increases, seems sometimes kamailio doesn't get the proper socket to forward the reply. I think the errors mainly are related to responses which are being forwarded, like if the function get_sock_info_list was not able to retrieve the listen interfaces we have tried to set in the onreply routes the commands set_recv_socket("udp:192.168.99.81:5060"); set_send_socket("udp:87.1.1.27:5060"); (when reply goes from private to public domain) and it seems it reduces the number of Sep 21 17:41:13 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155702]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:164.152.22.248:5060) Sep 21 17:41:13 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155698]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:208.74.138.184:5060) Sep 21 17:41:13 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155695]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:208.74.138.181:5060) Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155693]: ERROR: <core> [core/forward.c:183]: get_out_socket(): no corresponding socket found for(udp:38.102.250.60:5060) errors But i honestly don't know why the Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155707]: ERROR: tm [ut.h:302]: uri2dst2(): no corresponding socket for "87.1.1.27" af 2 Sep 21 17:41:14 lax-dedge-1 /usr/local/kamailio/sbin/kamailio[3155707]: ERROR: tm [t_fwd.c:470]: prepare_new_uac(): can't fwd to af 2, proto 1 (no corresponding listening socket) appear We aldso tried to increase the kernel buffers rmem and wmem from 208KB (as we had by default) to 4MB Do you know a reason which could cause these logs to appear? Any setup that could mitigate them? thanks a lot and regards david escartin -- <http://www.sonoc.io/> David Escartín NOC engineer www.sonoc.io [image: LinkedIn] <https://www.linkedin.com/company/sonoc> [image: Twitter] <https://twitter.com/sonoc_> [image: Instagram] <https://www.instagram.com/sonoc.io/> This e-mail is for the exclusive use of its recipients and may contain business secrets or other confidential or privileged information. Any unauthorised use, copying, publication or distribution of this e-mail is strictly prohibited. If you are not the intended recipient, please inform us immediately by replying to this e-mail and delete it, including any attachments or copies on your system. 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