Hi guys, I have OpensER 1.1.0 in fornt of 2 Asterisks servers. My OpenSER act as load balancer for outbound calls and for registrar server for inbound calls coming from Asterisks PSTN GW to Users

Some users, using AVM Fritz Fon Boxes cannot register on the proxy, they get a "483 Too Many Hops". They say it happens only if they configure the Fritx using FQDN of our proxy, if they put its IP addess in it they are having no problems... (it sounds very strange to me but I captured some trafic and had confirmation of what they're saying)

Here is a SIP dialog with the error message

Request-Line: REGISTER sip:sip.advancemedia.it SIP/2.0 Via: SIP/2.0/UDP 192.168.1.121:5060;branch=z9hG4bKC0F2D683E6BE8AC5F1A4A260BE120 Route: sip:sip.advancemedia.it;lr From: sip:cirifax@sip.advancemedia.it;tag=1898319928 To: sip:cirifax@sip.advancemedia.it Call-ID: 9ADCCD22187BDEC93B5953DD93E0F@192.168.1.121 CSeq: 1 REGISTER Max-Forwards: 70 User-Agent: AVM FRITZ!Box Fon ata 1020 11.04.01 (Jan 25 2006) Supported: 100rel, replaces Allow-Events: telephone-event, refer Allow: INVITE, ACK, OPTIONS, CANCEL, BYE, UPDATE, PRACK, INFO, SUBSCRIBE, NOTIFY, REFER, MESSAGE Accept: application/sdp, multipart/mixed Accept-Encoding: identity Content-Length: 0

Status-Line: SIP/2.0 483 Too Many Hops Message Header Via: SIP/2.0/UDP 192.168.1.121:5060;received=80.67.115.96;branch=z9hG4bKC0F2D683E6BE8AC5F1A4A260BE120 From: sip:cirifax@sip.advancemedia.it;tag=1898319928 To: sip:cirifax@sip.advancemedia.it;tag=b36cb132c8240044969e91db40b97d00.d5d1 Call-ID: 9ADCCD22187BDEC93B5953DD93E0F@192.168.1.121 CSeq: 1 REGISTER Server: OpenSer (1.1.0-notls (i386/linux)) Content-Length: 0 Warning: 392 213.92.79.131:5060 "Noisy feedback tells: pid=13326 req_src_ip=213.92.79.131 req_src_port=5060 in_uri=sip:sip.advancemedia.it out_uri=sip:sip.advancemedia.it via_cnt==71"

It doesn't happen if the user put the ip of the proxy server in the configuration of the Fritz

I guess it's a problem with loose routing but I cannot understand if it's a buggy implementation of SIP in the fritz or my misconfiguration

Here is my openser.cfg, tnx in advance for help.

Edoardo

# $Id: ser.cfg,v 1.21.4.1 2003/11/10 15:35:15 andrei Exp $ # ----------- global configuration parameters ------------------------

check_via=yes # (cmd. line: -v) dns=no # (cmd. line: -r) rev_dns=no # (cmd. line: -R) fifo="/tmp/ser_fifo"

# ------------------ module loading ---------------------------------- loadmodule "/usr/lib/openser/modules/sl.so" [...]

modparam("usrloc", "db_mode", 2) modparam("usrloc", "db_url", "mysql://user:pass@192.168.252.5/openser") modparam("usrloc", "timer_interval", 120) modparam("auth_db", "calculate_ha1", 0) modparam("auth_db", "db_url", "mysql://user:pass@192.168.252.5/db") modparam("uri_db", "db_url", "mysql://user:pass@192.168.252.5/openser") modparam("rr", "enable_full_lr", 1) modparam("registrar", "nat_flag", 6) modparam("registrar", "max_expires", 3600) modparam("registrar", "min_expires", 60) modparam("registrar", "append_branches", 0) modparam("registrar", "desc_time_order", 1) modparam("nathelper", "natping_interval", 20) # Ping interval 20 s modparam("nathelper", "ping_nated_only", 1) # Ping only clients behind NAT modparam("dispatcher", "force_dst", 1)

# ------------------------- request routing logic ------------------- # main routing logic

route{ if (!mf_process_maxfwd_header("10")) { sl_send_reply("483","Too Many Hops"); exit; }; if ( msg:len > max_len ) { sl_send_reply("513", "Message too big"); exit; };

if ( (method=="OPTIONS") || (method=="SUBSCRIBE") || (method=="NOTIFY") ) { sl_send_reply("405", "Method Not Allowed"); exit; }

# loose-route processing if (loose_route()) { # mark routing logic in request append_hf("P-hint: rr-enforced\r\n"); t_relay(); exit; }; if (!method=="REGISTER") { record_route(); };

if ((src_ip==ip.of.asterisk.1) || (src_ip==ip.of.asterisk.1)) { if (!lookup("location")) { sl_send_reply("486", "Busy here"); exit; };

t_on_reply("1"); if (!t_relay()) { sl_reply_error(); }; exit; };

if (nat_uac_test("3")) { if ((method=="REGISTER") || (method=="INVITE") || (method=="OPTIONS")) { fix_nated_contact(); force_rport(); setflag(6); # Mark as NATed } }

if (method=="REGISTER") { if (!proxy_authorize("exorsa", "openser_view")) { proxy_challenge("exorsa", "0"); exit; } if (!check_to()) { sl_send_reply("403", "Digest username and URI username do NOT match! Stay away!"); exit; }

save("location");

exit; };

if (method=="INVITE") { if (!proxy_authorize("exorsa", "openser_view")) { proxy_challenge("exorsa", "0"); exit; }

if (!check_from()) { sl_send_reply("403", "Digest username and URI username do NOT match! Stay away!"); exit; } }

if (!uri==myself) { # mark routing logic in request append_hf("P-hint: outbound\r\n"); route(1); exit; };

append_hf("P-hint: usrloc applied\r\n"); route(1); }

route[1] { # !! Nathelper if (uri=~"[@:](192.168.|10.|172.(1[6-9]|2[0-9]|3[0-1]).)" && !search("^Route:")){ sl_send_reply("479", "We don't forward to private IP addresses"); exit; };

# NAT processing of replies; apply to all transactions (for example, # re-INVITEs from public to private UA are hard to identify as # NATed at the moment of request processing); look at replies t_on_reply("1");

if ((src_ip!=ip.of.asterisk.1) && (src_ip!=ip.of.asterisk.2)) { ds_select_dst("1", "0"); }

if (!t_relay()) { sl_reply_error(); }; }

# !! Nathelper onreply_route[1] { # NATed transaction ? if (isflagset(6) && status =~ "(183)|2[0-9][0-9]") { fix_nated_contact(); # otherwise, is it a transaction behind a NAT and we did not # know at time of request processing ? (RFC1918 contacts) } else if (nat_uac_test("1")) { fix_nated_contact(); }; }