Hi all, before hand thanks for all the support received on this channel.

I have an issue with an installed server on a aws instance which is giving me routing loops, my setup is simple, i have alias set for both ips internal and external and the loop still present when t_relay don't find any routes to relay it just sent it to  itself with the public ip then the loop starts.

can any one please advise how can i prevent that or just tell t_relay that if there is no more routes just respond with a cancel or stop searching.

same thing happens when a gw code is not found on the dispatcher list file.

as i had read by just specifying the alias=domain it should take care of it but it is not happening perhaps because it is a AWS instance, or most likely i am missing something after the T_relay to stop the call from looping.

I do have several headers fix because i have an asterisk sending calls with lots of signalling calls added to the call that i need to remove before the call is passed out to a carrier or another UA, Kamailio is just proxing the calls between asterisk and the outside world no Media handling, No registrations.

 Again thanks for any tips to find my answer or if anyone had a similar issue thanks again.

thanks for any help .

Julian.

on this setup i have

public ip as 2.2.2.2

private IP as 1.1.1.1


#!KAMAILIO
####### Global Parameters #########

#!ifdef WITH_DEBUG
debug=4
log_stderror=yes
#!else
#debug=2
#log_stderror=yes
#!endif

memdbg=5
memlog=5

log_facility=LOG_LOCAL7

fork=yes
children=6

auto_aliases=no


listen=udp:1.1.1.1:5060 advertise 2.2.2.2:5060

alias=1.1.1.1:5060
alias=1.1.1.1
alias=2.2.2.2:5060
alias=2.2.2.2


port=5060

enable_tls=no

#tcp_connection_lifetime=3605

#!ifdef WITH_SRCPATH
mpath="modules_k:modules"
#!else
mpath="/usr/lib64/kamailio/modules_k/:/usr/lib64/kamailio/modules/"

#!endif
loadmodule "db_mysql.so"
##loadmodule "mi_fifo.so"
loadmodule "tm.so"
loadmodule "sl.so"
loadmodule "acc.so"
loadmodule "rr.so"
loadmodule "maxfwd.so"
loadmodule "uac.so"
loadmodule "textops.so"
loadmodule "pv.so"
loadmodule "dispatcher.so"
loadmodule "usrloc.so"
loadmodule "registrar.so"
loadmodule "siputils.so"
loadmodule "sanity.so"
loadmodule "ctl.so"
loadmodule "mi_rpc.so"
loadmodule "avpops.so"
#!ifdef WITH_NAT
loadmodule "nathelper.so"
loadmodule "rtpproxy.so"
#!endif
loadmodule "xlog.so"
##mysqlcdr
modparam("acc", "db_flag", 2)
modparam("acc", "db_missed_flag", 3)
modparam("acc", "report_cancels", 1)
modparam("acc", "db_url", "mysql://openser:password@1.1.1.2/openser")
modparam("acc", "db_extra", "from_uri=$fu; to_uri=$tu; intid=$fU; type_call=$si; dst_ip=$ru; carriercode=$tu;callmode=$var(out)" )

#loadmodule "carrierroute"
modparam("tm", "cancel_b_method", 1)
modparam("tm", "failure_reply_mode", 3)
modparam("tm", "fr_timer", 30000)
modparam("tm", "fr_inv_timer", 120000)

modparam("dispatcher", "list_file", "/etc/kamailio/dispatcher.lst")
modparam("rr", "enable_full_lr", 1)

#!ifdef WITH_NAT
# ----- rtpproxy params -----
modparam("rtpproxy", "rtpproxy_sock", "udp:127.0.0.1:7722")

# ----- nathelper params -----
modparam("nathelper", "natping_interval", 30)
modparam("nathelper", "ping_nated_only", 1)
modparam("nathelper", "sipping_bflag", FLB_NATSIPPING)
modparam("nathelper", "sipping_from", "sip:pinger@kamailio.org")
# ----- mi_fifo params -----

##modparam("mi_fifo", "fifo_name", "/tmp/kamailio_fifo")

# params needed for NAT traversal in other modules
modparam("nathelper|registrar", "received_avp", "$avp(RECEIVED)")
modparam("usrloc", "nat_bflag", FLB_NATB)
#!endif
modparam("xlog", "buf_size", 8192)
modparam("xlog", "force_color", 1)
#carrierroute
#modparam("carrierroute", "config_file", "/etc/kamailio/carrierroute.conf")
#end carrierroute

modparam("pv", "shvset", "ruta=s:$ru")
modparam("pv", "varset","in=s:IN")
modparam("pv", "varset","out=s:OUT")
#################BEGINING MAINROUTE##################
request_route {

        if (!mf_process_maxfwd_header("4")) {
                sl_send_reply("483","Too Many Hops");
drop;
                exit;
        }
##
 # initial sanity checks -- too long messages
       if (msg:len >=  2048 ) {
               sl_send_reply("513", "Message too big");
xlog("out header CHECK 513 baderror from_uri=$fu;($ct++)<$tU---=$var(n)> to_uri=$tu; intid=$fU; type_call=$si; dst_ip=$ru; carriercode=$var(z);callmode=$var(out)");
drop;
               exit;
       };
#
        if(is_method("OPTIONS")) {
            # send reply for each options request
            sl_send_reply("200", "ok");
            exit();
         }



#
if ( is_method("ACK") ) {
if ( t_check_trans() ) {
# no loose-route, but stateful ACK;
# must be an ACK after a 487
# or e.g. 404 from upstream server
$var(n)=$(tU{s.substr,3,0});
$var(i)=$(ct{re.subst,/^.*11811(.*)/"\1/});

$var(t)=$(fn{re.subst,/^.*11811(.*)/"\1/});

$var(r)=$rd; ##to domain
$fU=$(fU{s.substr,14,0});
$fn=$var(t);
$tU=$var(n);
$td=$var(r);

subst('/^Contact:.*11811(.*)$/Contact: <sip:\1\2/ig'); 

# Remove prefixes numbers from Contact\
t_relay();
exit;
} else {
# ACK without matching transaction ... ignore and discard
$var(n)=$(tU{s.substr,3,0});
$var(i)=$(ct{re.subst,/^.*11811(.*)/"\1/});

$var(t)=$(fn{re.subst,/^.*11811(.*)/"\1/});

$var(r)=$rd; ##to domain
$fU=$(fU{s.substr,14,0});
$fn=$var(t);
$tU=$var(n);
$td=$var(r);

subst('/^Contact:.*11811(.*)$/Contact: <sip:\1\2/ig');
t_relay();
exit;
}
}
##responding to bye requests and modifying headers to match invite
   if(method=="BYE") {
   #Account BYE transactions
#$var(d) = $tu;
#$var(e)=$(var(d){s.substr,4,3});
setflag(2);
setflag(10);
$var(n)=$(tU{s.substr,3,0});
$var(i)=$(ct{re.subst,/^.*11811(.*)/"\1/});

$var(t)=$(fn{re.subst,/^.*11811(.*)/"\1/});

$var(r)=$rd; ##to domain
$fU=$(fU{s.substr,14,0});
$fn=$var(t);
$tU=$var(n);
$td=$var(r);

subst('/^Contact:.*11811(.*)$/Contact: <sip:\1\2/ig');
t_relay();
        exit;
};

#CANCEL processing
if (method=="CANCEL") {
setflag(2);
setflag(3);
$var(n)=$(tU{s.substr,3,0});
$var(i)=$(ct{re.subst,/^.*11811(.*)/"\1/});

$var(t)=$(fn{re.subst,/^.*11811(.*)/"\1/});

$var(r)=$rd; ##to domain
$fU=$(fU{s.substr,14,0});
$fn=$var(t);
$tU=$var(n);
$td=$var(r);

subst('/^Contact:.*11811(.*)$/Contact: <sip:\1\2/ig');
t_relay();
        exit;
##if (t_check_trans()) t_relay();

exit;
};


#


#
       if (loose_route()) {


##
if(is_method("OPTIONS")) {
            # send reply for each options request
            sl_send_reply("200", "ok");
            exit();
         }
##
if(method=="BYE") {
   #Account BYE transactions
setflag(2);
};


##CANCEL processing
if (method=="CANCEL") {
setflag(3);
$var(n)=$(tU{s.substr,3,0});
$var(i)=$(ct{re.subst,/^.*11811(.*)/"\1/});

$var(t)=$(fn{re.subst,/^.*11811(.*)/"\1/});

$var(r)=$rd; ##to domain
$fU=$(fU{s.substr,14,0});
$fn=$var(t);
$tU=$var(n);
$td=$var(r);
subst('/^Contact:.*11811(.*)$/Contact: <sip:\1\2/ig');
if (t_check_trans()) t_relay();
exit;
};                

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


 if (is_method("INVITE")) { #Procesing invites


record_route();
              
        }
##LOGGING CALL BEFORE IS PROCESSED
xlog("before strip,< time [$Tf] > Aip= $src_ip, r-uri($ru\n");
xlog("before from_uri=$fu; to_uri=$tu; pai=<<$ct>>;intid=$fU; type_call=$si; dst_ip=$ru; carriercode=$tu;callmode=$var(out) --$$--$ou");
#creando rutas
setflag(2);
# Account Missed calls
setflag(3);
###VARIABLES FOR MODIFICATIONS
$var(x) = $(ru);

$var(y)=$(var(x){s.substr,4,3}); 

$var(z)=$(var(y){s.int});

$var(t)=$(var(x){s.substr,7,0});

$var(h)=$(var(x){s.substr,0,7});

$var(o)=$(fU{s.substr,14,0});

if($(var(x){s.len}) < 3)
{
 $var(z)='0'+ $var(z);
}

xlog("dsroute $var(z)fullruri($ru)\n");


strip(3);

xlog("after strip time [$Tf] method ($rm) via el code ($var(z)--varhex($var(h))-- ($var(y))\n");
xlog("after from_uri=$fu; to_uri=$tu; intid=$fU; type_call=$si; dst_ip=$ru; carriercode=$var(z);callmode=$var(out)");

ds_select_domain ("$var(z)", "4");#carrer dynamic


###########KILLING BUGGIES#######when t_realy fails to find a route a loop is generate then strip takes off a digit until 0@2.2.2.2 is left for to: user this kills that call.#####
if ($(tU{s.len}) < 4) {
xlog("CHECK TU 1bad kILLING BUGGIES>>> $tu--$td-$tU-$tt--$dd-$dd-$du- -<<$rd>$ru --- $oU> pai+++ <<$ct>>++ from_uri=$fu;<$tU---=$var(n)> to_uri=$tu; }pai<$ai> id=$fU; type_call=$si; dst_ip=$ru; carriercode=$var(z);callmode=$var(out)");
##sl_reply_error();
##sl_send_reply("513", "Message too big");
##sl_send_reply("488","Not Acceptable Here");
sl_send_reply("488","Not Acceptable Here");
#t_reset_retr();
#t_release();
##if(!t_relay()){ sl_reply_error(); drop; exit;}

#if (!t_relay()) { sl_reply_error(); break; };
# t_relay();
#setflag(2);
drop;
exit;

}; ## Endif less than 4
##############END KILLING###########
################ROUTE SELECTION###############
if($(fn{s.len}) > 10) { # IF WE CHECK FOR FROM: ROUTEID MUST BE LONGER THAN 10 DIGITS TO BE A VALID ROUTE

xlog("out header CHECK more than 10 digits BEFORE from_uri=$fu;($ct++)<$tU---=$var(n)> to_uri=$tu; intid=$fU; type_call=$si; dst_ip=$ru; carriercode=$var(z);callmode=$var(out)");
$var(n)=$(tU{s.substr,3,0});
$var(i)=$(ct{re.subst,/^.*00700(.*)/"\1/});
$var(t)=$(fn{re.subst,/^.*00700(.*)/"\1/});
$var(r)=$rd; ##to domain
$fU=$(fU{s.substr,14,0});
$fn=$var(t);
$tU=$var(n);
$td=$var(r);

subst('/^Contact:.*11811(.*)$/Contact: <sip:\1\2/ig'); # Remove number from Contact

##if(!t_relay()){ sl_reply_error(); drop; exit;}

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

# t_relay();

drop;
 exit;

};

################ENDrouteselect##############################


###############AFTER LAST IF##############reply 488 ANY CALL THAT DID NOT FOUND A ROUTE.
sl_send_reply("488","Not Acceptable Here");
drop;
exit;
}

###################END MAINROUTE#################





On My dispatcher.lst i have 


1 sip:1.1.1.1:5060
2 sip:2.2.2.2:5060
3 sip:3.3.3.3:5060
3 sip:3.3.3.5:5060
...