Hi, I noticed that if I enable tcp_accept_haproxy kamailio still can accept connections without the PROXY-protocol header. The documentation on the wiki has the following note: "Please note that enabling this option will reject any inbound TCP connection that does not conform to the PROXY-protocol spec." https://www.kamailio.org/wiki/cookbooks/devel/core#tcp_accept_haproxy This could be true up until a specific version of kamalio but from 5.7.4+ this limitation is seems to be removed. Enabling tcp_accept_haproxy is breaking the outbound/rr module because it con’t find the socket based on the address and port from the flow token. The flow tokens created by a REGISTER on a connection without a PROXY header can be used. Flow tokens created from a connection with PROXY-protocol header will fail with "cannot find socket from flow-token” once loose_route is invoked. loose.c:561 /* First, force the local socket */ si = find_si(&rcv->dst_ip, rcv->dst_port, rcv->proto); if(si) set_force_socket(_m, si); else { LM_INFO("cannot find socket from flow-token\n"); return -1; } I’m not sure if the address and/or port values stored in the flow token are incorrect or the problem lies in the matiching in find_is(…). Wolter