[Users] Error when trying to lookup locations in a non local database

I have three sip proxies configured with OpenSER and MediaProxy for NAT traversal support, I'm going to call them Proxy A, B and C. These proxies work together as a farm; the Proxies A and C points to the MySql database installed in Proxy B. Proxy B serves as location server an also as proxy. Everything works fine, the REGISTER requests are validated against the database (installed in Proxy B) by any proxy without any problem. Also, the location records are inserted without any problem. However, I noticed when Proxies A or C receive an INVITE request, they respond 404 - User Not Found. I made a lot of debug, captures and anything else, and I found the lookup function is only getting locations for user agents registered by the Proxy that is making the query; in other words, if the user X registers through Proxy A, then an INVITE request received by Proxy A to user X is routed successfully. I don't know if I'm missing something. I'm using db_mode 1 for usrloc to store locations directly in the database. Below is one of my configuration scripts, the three are practically the same, they are different on the listen IP addresses and in the record route for nated clients. I'll appreciate any help. Thank you # ----------- global configuration parameters ------------------------ debug=9 # debug level (cmd line: -dddddddddd) fork=yes log_stderror=no # (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=AAA.BBB.CCC.DDD port=5060 children=4 fifo="/tmp/openser_fifo" fifo_db_url="mysql://openser:password@dbs.sip.mydomain.com/openser" #Aliases alias="sip.mydomain.com" # # uncomment the following lines for TLS support #disable_tls = 0 #listen = tls:your_IP:5061 #tls_verify = 1 #tls_require_certificate = 0 #tls_method = TLSv1 #tls_certificate = "/usr/local/etc/openser/tls/user/user-cert.pem" #tls_private_key = "/usr/local/etc/openser/tls/user/user-privkey.pem" #tls_ca_list = "/usr/local/etc/openser/tls/user/user-calist.pem" # ------------------ module loading ---------------------------------- loadmodule "/usr/local/lib/openser/modules/mysql.so" loadmodule "/usr/local/lib/openser/modules/sl.so" loadmodule "/usr/local/lib/openser/modules/tm.so" loadmodule "/usr/local/lib/openser/modules/rr.so" loadmodule "/usr/local/lib/openser/modules/maxfwd.so" loadmodule "/usr/local/lib/openser/modules/usrloc.so" loadmodule "/usr/local/lib/openser/modules/registrar.so" loadmodule "/usr/local/lib/openser/modules/auth.so" loadmodule "/usr/local/lib/openser/modules/auth_db.so" loadmodule "/usr/local/lib/openser/modules/alias_db.so" loadmodule "/usr/local/lib/openser/modules/uri.so" loadmodule "/usr/local/lib/openser/modules/uri_db.so" loadmodule "/usr/local/lib/openser/modules/domain.so" loadmodule "/usr/local/lib/openser/modules/mediaproxy.so" loadmodule "/usr/local/lib/openser/modules/nathelper.so" loadmodule "/usr/local/lib/openser/modules/textops.so" loadmodule "/usr/local/lib/openser/modules/xlog.so" # ----------------- setting module-specific parameters --------------- modparam("usrloc|auth_db|domain|uri_db|alias_db", "db_url", "mysql://openser:password@dbs.sip.mydomain.com/openser") modparam("usrloc", "use_domain", 0) modparam("usrloc", "db_mode", 1) modparam("usrloc", "timer_interval", 60) modparam("registrar", "use_domain", 0) modparam("registrar", "nat_flag", 6) modparam("registrar", "min_expires", 10) modparam("registrar", "max_expires", 80) modparam("registrar", "default_expires", 30) modparam("rr", "enable_full_lr", 1) modparam("auth_db", "calculate_ha1", yes) modparam("auth_db", "password_column", "password") modparam("nathelper", "rtpproxy_disable", 1) modparam("nathelper", "natping_interval", 0) modparam("mediaproxy","natping_interval", 30) #modparam("mediaproxy","mediaproxy_socket", "/var/run/mediaproxy.sock") modparam("mediaproxy","mediaproxy_socket", "/var/run/proxydispatcher.sock") modparam("mediaproxy","sip_asymmetrics","/usr/local/etc/openser/sip-clie nts") modparam("mediaproxy","rtp_asymmetrics","/usr/local/etc/openser/rtp-clie nts") # ------------------------- request routing logic ------------------- # main routing logic route { # ----------------------------------------------------------------- # Sanity Check Section # ----------------------------------------------------------------- if (!mf_process_maxfwd_header("10")) { sl_send_reply("483", "Too Many Hops"); exit; }; if (msg:len > max_len) { sl_send_reply("513", "Message Overflow"); exit; }; # ----------------------------------------------------------------- # Record Route Section # ----------------------------------------------------------------- if (method=="INVITE" && client_nat_test("3")) { record_route_preset("AAA.BBB.CCC.DDD:5060;nat=yes"); } else if (method!="REGISTER") { record_route(); }; # ----------------------------------------------------------------- # Call Tear Down Section # ----------------------------------------------------------------- if (method=="BYE" || method=="CANCEL") { end_media_session(); }; # ----------------------------------------------------------------- # Loose Route Section # ----------------------------------------------------------------- if (loose_route()) { if (has_totag() && (method=="INVITE" || method=="ACK")) { if (client_nat_test("3") || search("^Route:.*;nat=yes")) { setflag(6); use_media_proxy(); }; }; route(1); exit; }; # ----------------------------------------------------------------- # Call Type Processing Section # ----------------------------------------------------------------- if (uri!=myself) { route(4); route(1); exit; }; if (method=="CANCEL") { route(1); exit; } else if (method=="INVITE") { route(3); exit; } else if (method=="REGISTER") { route(2); exit; } else if (method=="ACK") { exit; }; if (uri!=myself) { route(4); route(1); exit; }; if (!lookup("location")) { sl_send_reply("404", "User Not Found"); exit; }; route(1); } route[1] { # ----------------------------------------------------------------- # Default Message Handler # ----------------------------------------------------------------- t_on_reply("1"); if (!t_relay()) { if (method=="INVITE" || method=="ACK") { end_media_session(); }; sl_reply_error(); }; } route[2] { # ----------------------------------------------------------------- # REGISTER Message Handler # ---------------------------------------------------------------- xlog("L_INFO", "REGISTER - entering section\n"); #if (!search("^Contact:[ ]*\*") && client_nat_test("7")) { if (client_nat_test("7")) { setflag(6); fix_nated_register(); force_rport(); xlog("L_INFO", "REGISTER - nated client detected and fixed ($tu)\n"); }; if (registered("location")) { xlog("L_INFO", "REGISTER - user already registered ($tu)\n"); }; if (!www_authorize("sip.mydomain.com","subscriber")) { www_challenge("sip.mydomain.com","0"); exit; }; if (!check_to()) { xlog("L_WARN", "REGISTER - unauthorized client ($tu)\n"); sl_send_reply("401", "Unauthorized"); exit; }; consume_credentials(); xlog("L_INFO", "REGISTER - client authorized ($tu)\n"); if (!save("location")) { xlog("L_WARN", "REGISTER - client location could not be saved ($tu)\n"); sl_reply_error(); }; xlog("L_INFO", "REGISTER - client location saved ($tu)\n"); } route[3] { # ----------------------------------------------------------------- # INVITE Message Handler # ----------------------------------------------------------------- xlog("L_INFO", "INVITE - entering section\n"); #if (client_nat_test("3")) { if (client_nat_test("7")) { setflag(7); fix_nated_contact(); force_rport(); }; if (!proxy_authorize("sip.mydomain.com","subscriber")) { proxy_challenge("sip.mydomain.com","0"); exit; } else if (!check_from()) { sl_send_reply("403", "Use From=ID"); exit; }; consume_credentials(); xlog("L_INFO", "INVITE - proxy authorized\n"); if (uri!=myself) { xlog("L_INFO", "INVITE - <$ru> uri is not from here, routing out\n"); route(4); route(1); exit; }; xlog("L_INFO", "INVITE - before aliases lookup <$ru>\n"); alias_db_lookup("dbaliases"); xlog("L_INFO", "INVITE - after aliases lookup <$ru>\n"); if (registered("location")) { xlog("L_INFO", "INVITE - the user is already registered <$ru>\n"); }; if (!lookup("location")) { xlog("L_WARN", "INVITE - not located <$ru>\n"); sl_send_reply("404", "User Not Found"); exit; }; route(4); route(1); } route[4] { # ----------------------------------------------------------------- # NAT Traversal Section # ----------------------------------------------------------------- if (isflagset(6) || isflagset(7)) { xlog("L_INFO", "NAT Traversal - using media proxy\n"); use_media_proxy(); }; } onreply_route[1] { if ((isflagset(6) || isflagset(7)) && (status=~"(180)|(183)|2[0-9][0-9]")) { if (!search("^Content-Length:[ ]*0")) { use_media_proxy(); }; }; if (client_nat_test("1")) { fix_nated_contact(); }; }