Im following "Getting Started with SER" and I'm stuck on the chapter about nat traversal Ive tried both methods, currently im working on rtpptoxy. the exact errors I get when i try to make calls from behind NAT are: 0(1731) WARNING: rtpp_test: can't get version of the RTP proxy 0(1731) WARNING: rtpp_test: support for RTP proxy has been disabled 0(1731) ERROR: force_rtp_proxy2: support for RTP proxy is disabled i have compiled and installed rtpproxy, and made sure the permissions were set. bmy bin # ps ax|grep rtp 1714 ? Ss 0:00 ./rtpproxy bmy bin # ls -la /var/run/rtpproxy.* -rw-r--r-- 1 root root 5 Nov 1 19:27 /var/run/rtpproxy.pid srwxr-xr-x 1 root root 0 Nov 1 19:27 /var/run/rtpproxy.sock i have attached my ser.cfg but below are some of the parts of it debug=3 # debug level (cmd line: -dddddddddd) fork=no log_stderror=yes # (cmd line: -E) /* Uncomment these lines to enter debugging mode fork=no log_stderror=yes */ check_via=no # (cmd. line: -v) dns=no # (cmd. line: -r) rev_dns=no # (cmd. line: -R) listen=10.0.0.10 alias=hostname.dyndns.org port=6060 children=4 fifo="/tmp/ser_fifo" fifo_db_url="mysql://user:pw@localhost/ser" <skip> modparam("nathelper", "rtpproxy_sock", "unix:/var/run/rtpproxy.sock") <skip> route{ # initial sanity checks -- messages with # max_forwards==0, or excessively long requests if (!mf_process_maxfwd_header("10")) { sl_send_reply("483","Too Many Hops"); break; }; if (msg:len >= 2048 ) { sl_send_reply("513", "Message too big"); break; }; # we record-route all messages -- to make sure that # subsequent messages will go through our proxy; that's # particularly good if upstream and downstream entities # use different transport protocol if (method!="REGISTER") { record_route(); }; if (method=="BYE" || method=="CANCEL") { unforce_rtp_proxy(); } # subsequent messages withing a dialog should take the # path determined by record-routing if (loose_route()) { if ((method=="INVITE" || method=="REFER") && !has_totag()) { sl_send_reply("403", "Forbidden"); break; }; if (method=="INVITE") { if (!proxy_authorize("","subscriber")) { proxy_challenge("","0"); break; }else if (!check_from()) { sl_send_reply("403", "Use From=ID"); break; }; consume_credentials(); if (nat_uac_test("19")) { setflag(6); force_rport(); fix_nated_contact(); }; force_rtp_proxy("l"); }; route(1); break; }; #======= call type processing section if (!uri==myself) { append_hf("P-hint: outbound\r\n"); route(4); route(1); break; }; if (method=="ACK") { route(1); break; } else if (method=="CANCEL") { route(1); break; } else if (method=="INVITE") { route(3); break; } else if (method=="REGISTER") { route(2); break; }; lookup("aliases"); if (uri!=myself) { route(4); route(1); break; }; if (!lookup("location")) { sl_send_reply("404", "User Not Found"); break; }; route(1); } route[1] { t_on_reply("1"); # send it out now; use stateful forwarding as it works reliably # even for UDP2TCP if (!t_relay()) { if (method=="INVITE" || isflagset(6)) { unforce_rtp_proxy(); }; sl_reply_error(); }; } route[2] { #------------------------- #REGISTER Message Handler #------------------------- if (!search("^Contact:[ ]*\*") && nat_uac_test("19")) { setflag(6); fix_nated_register(); force_rport(); }; sl_send_reply("100", "Trying"); if (!www_authorize("","subscriber")) { www_challenge("","0"); break; }; if (!check_to()) { sl_send_reply("401", "Unauthorized"); break; }; consume_credentials(); if (!save("location")) { sl_reply_error(); }; } route[3] { #---------- #--INVITE Message Handler #----------- if (!proxy_authorize("","subscriber")) { proxy_challenge("","0"); break; } else if (!check_from()) { sl_send_reply("403", "Use From=ID"); break; }; consume_credentials(); if (nat_uac_test("19")) { setflag(6); } lookup("aliases"); if (uri!=myself) { route(4); route(1); break; }; if (!lookup("location")) { sl_send_reply("404", "User Not Found"); break; }; route(4); route(1); } route[4] { #NAT Traversal if (isflagset(6)) { force_rport(); fix_nated_contact(); force_rtp_proxy(); } } onreply_route[1] { if (isflagset(6) && status=~"(180)|(183)|2[0-9][0-9]") { if (!search("^Contact-Length:[ ]*0")) { force_rtp_proxy(); }; }; if (nat_uac_test("1")) { fix_nated_contact(); }; }