src/modules/db_cassandra/kamailio_cassa.cfg
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 #!KAMAILIO
 #
 # Kamailio (OpenSER) SIP Server v3.1 - default configuration script
 #     - web: http://www.kamailio.org
 #     - git: http://sip-router.org
 #
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 # Direct your questions about this file to: <sr-users@lists.kamailio.org>
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 #
 # Refer to the Core CookBook at http://www.kamailio.org/dokuwiki/doku.php
 # for an explanation of possible statements, functions and parameters.
 #
 # Several features can be enabled using '#!define WITH_FEATURE' directives:
 #
 # *** To run in debug mode: 
 #     - define WITH_DEBUG
 #
 # *** To enable mysql: 
 #     - define WITH_MYSQL
 #
 # *** To enable authentication execute:
 #     - enable mysql
 #     - define WITH_AUTH
 #     - add users using 'kamctl'
 #
 # *** To enable IP authentication execute:
 #     - enable mysql
 #     - enable authentication
 #     - define WITH_IPAUTH
 #     - add IP addresses with group id '1' to 'address' table
 #
 # *** To enable persistent user location execute:
 #     - enable mysql
 #     - define WITH_USRLOCDB
 #
 # *** To enable presence server execute:
 #     - enable mysql
 #     - define WITH_PRESENCE
 #
 # *** To enable nat traversal execute:
 #     - define WITH_NAT
 #     - install RTPProxy: http://www.rtpproxy.org
 #     - start RTPProxy:
 #        rtpproxy -l _your_public_ip_ -s udp:localhost:7722
 #
 # *** To enable PSTN gateway routing execute:
 #     - define WITH_PSTN
 #     - set the value of pstn.gw_ip
 #     - check route[PSTN] for regexp routing condition
 #
 # *** To enable database aliases lookup execute:
 #     - enable mysql
 #     - define WITH_ALIASDB
 #
 # *** To enable multi-domain support execute:
 #     - enable mysql
 #     - define WITH_MULTIDOMAIN
 #
 # *** To enable TLS support execute:
 #     - adjust CFGDIR/tls.cfg as needed
 #     - define WITH_TLS
 #
 # *** To enable XMLRPC support execute:
 #     - define WITH_XMLRPC
 #     - adjust route[XMLRPC] for access policy
 #
 # *** To enable anti-flood detection execute:
 #     - adjust pike and htable=>ipban settings as needed (default is
 #       block if more than 16 requests in 2 seconds and ban for 300 seconds)
 #     - define WITH_ANTIFLOOD
 #
 # *** To enhance accounting execute:
 #     - enable mysql
 #     - define WITH_ACCDB
 #     - add following columns to database
 #!ifdef ACCDB_COMMENT
   ALTER TABLE acc ADD COLUMN src_user VARCHAR(64) NOT NULL DEFAULT '';
   ALTER TABLE acc ADD COLUMN src_domain VARCHAR(128) NOT NULL DEFAULT '';
   ALTER TABLE acc ADD COLUMN dst_ouser VARCHAR(64) NOT NULL DEFAULT '';
   ALTER TABLE acc ADD COLUMN dst_user VARCHAR(64) NOT NULL DEFAULT '';
   ALTER TABLE acc ADD COLUMN dst_domain VARCHAR(128) NOT NULL DEFAULT '';
   ALTER TABLE missed_calls ADD COLUMN src_user VARCHAR(64) NOT NULL DEFAULT '';
   ALTER TABLE missed_calls ADD COLUMN src_domain VARCHAR(128) NOT NULL DEFAULT '';
   ALTER TABLE missed_calls ADD COLUMN dst_ouser VARCHAR(64) NOT NULL DEFAULT '';
   ALTER TABLE missed_calls ADD COLUMN dst_user VARCHAR(64) NOT NULL DEFAULT '';
   ALTER TABLE missed_calls ADD COLUMN dst_domain VARCHAR(128) NOT NULL DEFAULT '';
 #!endif
 
 ####### Defined Values #########
 # *** Value defines - IDs used later in config
 #!ifdef WITH_MYSQL
 # - database URL - used to connect to database server by modules such
 #       as: auth_db, acc, usrloc, a.s.o.
 
 
 #!endif
 #!ifdef WITH_MULTIDOMAIN
 # - the value for 'use_domain' parameters
 #!define MULTIDOMAIN 1
 #!else
 #!define MULTIDOMAIN 0
 #!endif
 
 # - flags
 #   FLT_ - per transaction (message) flags
 #	FLB_ - per branch flags
 #!define FLT_ACC 1
 #!define FLT_ACCMISSED 2
 #!define FLT_ACCFAILED 3
 #!define FLT_NATS 5
 
 #!define FLB_NATB 6
 #!define FLB_NATSIPPING 7
 
 # my defines
 #!define WITH_DEBUG
 #!define LOCAL_TEST_RUN
 #!define WITH_AUTH
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 #!define DBURL "cassandra://:@127.0.0.1:9160/kamailio"
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 ####### Global Parameters #########
 
 #!ifdef WITH_DEBUG
 debug=5
 log_stderror=yes
 #!else
 debug=2
 log_stderror=no
 #!endif
 
 memdbg=7
 memlog=7
 
 log_facility=LOG_LOCAL0
 
 fork=yes
 children=4
 
 /* uncomment the next line to disable TCP (default on) */
 #disable_tcp=yes
 
 /* uncomment the next line to disable the auto discovery of local aliases
    based on reverse DNS on IPs (default on) */
 #auto_aliases=no
 
 /* add local domain aliases */
 #alias="sip.mydomain.com"
 
 /* uncomment and configure the following line if you want Kamailio to 
    bind on a specific interface/port/proto (default bind on all available) */
 
 listen=udp:10.10.10.10:5060
 /* port to listen to
  * - can be specified more than once if needed to listen on many ports */
 #port=5060
 
 #!ifdef WITH_TLS
 enable_tls=yes
 #!endif
 
 ####### Custom Parameters #########
 
 # These parameters can be modified runtime via RPC interface
 # - see the documentation of 'cfg_rpc' module.
 #
 # Format: group.id = value 'desc' description
 # Access: $sel(cfg_get.group.id) or @cfg_get.group.id
 #
 
 #!ifdef WITH_PSTN
 # PSTN GW Routing
 #
 # - pstn.gw_ip: valid IP or hostname as string value, example:
 # pstn.gw_ip = "10.0.0.101" desc "My PSTN GW Address"
 #
 # - by default is empty to avoid misrouting
 pstn.gw_ip = "" desc "PSTN GW Address"
 #!endif
 
 
 ####### Modules Section ########
 
 # set paths to location of modules
 #!ifdef LOCAL_TEST_RUN
 mpath="modules_k:modules"
 #!else
 mpath="/usr/local/lib/kamailio/modules_k/:/usr/local/lib/kamailio/modules/"
 #!endif
 
 #!ifdef WITH_MYSQL
 loadmodule "db_mysql.so"
 #!endif
 
 #my modules
 loadmodule "db_cassandra.so"
 
 loadmodule "mi_fifo.so"
 loadmodule "kex.so"
 loadmodule "tm.so"
 loadmodule "tmx.so"
 loadmodule "sl.so"
 loadmodule "rr.so"
 loadmodule "pv.so"
 loadmodule "maxfwd.so"
 loadmodule "usrloc.so"
 loadmodule "registrar.so"
 loadmodule "textops.so"
 loadmodule "siputils.so"
 loadmodule "xlog.so"
 loadmodule "sanity.so"
 loadmodule "ctl.so"
 loadmodule "mi_rpc.so"
 loadmodule "acc.so"
 
 #!ifdef WITH_AUTH
 loadmodule "auth.so"
 loadmodule "auth_db.so"
 #!ifdef WITH_IPAUTH
 loadmodule "permissions.so"
 #!endif
 #!endif
 
 #!ifdef WITH_ALIASDB
 loadmodule "alias_db.so"
 #!endif
 
 #!ifdef WITH_MULTIDOMAIN
 loadmodule "domain.so"
 #!endif
 
 #!ifdef WITH_PRESENCE
 loadmodule "presence.so"
 loadmodule "presence_xml.so"
 #!endif
 
 #!ifdef WITH_NAT
 loadmodule "nathelper.so"
 loadmodule "rtpproxy.so"
 #!endif
 
 #!ifdef WITH_TLS
 loadmodule "tls.so"
 #!endif
 
 #!ifdef WITH_ANTIFLOOD
 loadmodule "htable.so"
 loadmodule "pike.so"
 #!endif
 
 #!ifdef WITH_XMLRPC
 loadmodule "xmlrpc.so"
 #!endif
 
 
 # ----------------- setting module-specific parameters ---------------
 
 
 # ----- mi_fifo params -----
 modparam("mi_fifo", "fifo_name", "/tmp/kamailio_fifo")
 
 
 # ----- tm params -----
 # auto-discard branches from previous serial forking leg
 modparam("tm", "failure_reply_mode", 3)
 # default retransmission timeout: 30sec
 modparam("tm", "fr_timer", 30000)
 # default invite retransmission timeout after 1xx: 120sec
 modparam("tm", "fr_inv_timer", 120000)
 
 
 # ----- rr params -----
 # add value to ;lr param to cope with most of the UAs
 modparam("rr", "enable_full_lr", 1)
 # do not append from tag to the RR (no need for this script)
 modparam("rr", "append_fromtag", 0)
 
 
 # ----- registrar params -----
 modparam("registrar", "method_filtering", 1)
 /* uncomment the next line to disable parallel forking via location */
 # modparam("registrar", "append_branches", 0)
 /* uncomment the next line not to allow more than 10 contacts per AOR */
 #modparam("registrar", "max_contacts", 10)
 modparam("registrar", "max_expires", 120)
 
 
 # ----- acc params -----
 /* what special events should be accounted ? */
 modparam("acc", "early_media", 0)
 modparam("acc", "report_ack", 0)
 modparam("acc", "report_cancels", 0)
 /* by default ww do not adjust the direct of the sequential requests.
    if you enable this parameter, be sure the enable "append_fromtag"
    in "rr" module */
 modparam("acc", "detect_direction", 0)
 /* account triggers (flags) */
 modparam("acc", "log_flag", FLT_ACC)
 modparam("acc", "log_missed_flag", FLT_ACCMISSED)
 modparam("acc", "log_extra", 
 	"src_user=$fU;src_domain=$fd;dst_ouser=$tU;dst_user=$rU;dst_domain=$rd")
 modparam("acc", "failed_transaction_flag", FLT_ACCFAILED)
 /* enhanced DB accounting */
 #!ifdef WITH_ACCDB
 modparam("acc", "db_flag", FLT_ACC)
 modparam("acc", "db_missed_flag", FLT_ACCMISSED)
 modparam("acc", "db_url", DBURL)
 modparam("acc", "db_extra",
 	"src_user=$fU;src_domain=$fd;dst_ouser=$tU;dst_user=$rU;dst_domain=$rd")
 #!endif
 
 
 # ----- usrloc params -----
 /* enable DB persistency for location entries */
 modparam("usrloc", "db_url", DBURL)
 modparam("usrloc", "db_mode", 3)
 modparam("usrloc", "db_update_as_insert", 1)
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 modparam("usrloc", "timer_interval", 0)
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 #modparam("usrloc", "use_domain", MULTIDOMAIN)
 
 
 # ----- auth_db params -----
 #!ifdef WITH_AUTH
 modparam("auth_db", "db_url", DBURL)
 modparam("auth_db", "calculate_ha1", yes)
 modparam("auth_db", "password_column", "password")
 modparam("auth_db", "load_credentials", "")
 #modparam("auth_db", "use_domain", MULTIDOMAIN)
 
 # ----- permissions params -----
 #!ifdef WITH_IPAUTH
 modparam("permissions", "db_url", DBURL)
 modparam("permissions", "db_mode", 1)
 #!endif
 
 #!endif
 
 
 # ----- alias_db params -----
 #!ifdef WITH_ALIASDB
 modparam("alias_db", "db_url", DBURL)
 modparam("alias_db", "use_domain", MULTIDOMAIN)
 #!endif
 
 
 # ----- domain params -----
 #!ifdef WITH_MULTIDOMAIN
 modparam("domain", "db_url", DBURL)
 # use caching
 modparam("domain", "db_mode", 1)
 # register callback to match myself condition with domains list
 modparam("domain", "register_myself", 1)
 #!endif
 
 
 #!ifdef WITH_PRESENCE
 # ----- presence params -----
 modparam("presence", "db_url", DBURL)
 
 # ----- presence_xml params -----
 modparam("presence_xml", "db_url", DBURL)
 modparam("presence_xml", "force_active", 1)
 #!endif
 
 
 #!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")
 
 # params needed for NAT traversal in other modules
 modparam("nathelper|registrar", "received_avp", "$avp(RECEIVED)")
 modparam("usrloc", "nat_bflag", FLB_NATB)
 #!endif
 
 
 #!ifdef WITH_TLS
 # ----- tls params -----
 modparam("tls", "config", "/usr/local/etc/kamailio/tls.cfg")
 #!endif
 
 #!ifdef WITH_ANTIFLOOD
 # ----- pike params -----
 modparam("pike", "sampling_time_unit", 2)
 modparam("pike", "reqs_density_per_unit", 16)
 modparam("pike", "remove_latency", 4)
 
 # ----- htable params -----
 # ip ban htable with autoexpire after 5 minutes
 modparam("htable", "htable", "ipban=>size=8;autoexpire=300;")
 #!endif
 
 #!ifdef WITH_XMLRPC
 # ----- xmlrpc params -----
 modparam("xmlrpc", "route", "XMLRPC");
 modparam("xmlrpc", "url_match", "^/RPC")
 #!endif
 
 # db_cassandra parameters
 modparam("db_cassandra", "schema_path", "/usr/local/sip-router/etc/kamctl/dbcassandra");
 
 # my parameters
 
 ####### Routing Logic ########
 
 
 # Main SIP request routing logic
 # - processing of any incoming SIP request starts with this route
 route {
 
 	# per request initial checks
 	route(REQINIT);
 
 	# NAT detection
 	route(NAT);
 
 	# handle requests within SIP dialogs
 	route(WITHINDLG);
 
 	# CANCEL processing
 	if (is_method("CANCEL"))
 	{
 		if (t_check_trans())
 			t_relay();
 		exit;
 	}
 
 	t_check_trans();
 
 	# authentication
 	route(AUTH);
 
 	# record routing for dialog forming requests (in case they are routed)
 	# - remove preloaded route headers
 	remove_hf("Route");
 	if (is_method("INVITE|SUBSCRIBE"))
 		record_route();
 
 	# account only INVITEs
 	if (is_method("INVITE"))
 	{
 		setflag(FLT_ACC); # do accounting
 	}
 
 	# dispatch requests to foreign domains
 	route(SIPOUT);
 
 	### requests for my local domains
 
 	# handle presence related requests
 	route(PRESENCE);
 
 	# handle registrations
 	route(REGISTRAR);
 
 	if ($rU==$null)
 	{
 		# request with no Username in RURI
 		sl_send_reply("484","Address Incomplete");
 		exit;
 	}
 
 	# dispatch destinations to PSTN
 	route(PSTN);
 
 	# user location service
 	route(LOCATION);
 
 	route(RELAY);
 }
 
 
 route[RELAY] {
 #!ifdef WITH_NAT
 	if (check_route_param("nat=yes")) {
 		setbflag(FLB_NATB);
 	}
 	if (isflagset(FLT_NATS) || isbflagset(FLB_NATB)) {
 		route(RTPPROXY);
 	}
 #!endif
 
 	/* example how to enable some additional event routes */
 	if (is_method("INVITE")) {
 		#t_on_branch("BRANCH_ONE");
 		t_on_reply("REPLY_ONE");
 		t_on_failure("FAIL_ONE");
 	}
 
 	if (!t_relay()) {
 		sl_reply_error();
 	}
 	exit;
 }
 
 # Per SIP request initial checks
 route[REQINIT] {
 #!ifdef WITH_ANTIFLOOD
 	# flood dection from same IP and traffic ban for a while
 	# be sure you exclude checking trusted peers, such as pstn gateways
 	# - local host excluded (e.g., loop to self)
 	if(src_ip!=myself)
 	{
 		if($sht(ipban=>$si)!=$null)
 		{
 			# ip is already blocked
 			xdbg("request from blocked IP - $rm from $fu (IP:$si:$sp)\n");
 			exit;
 		}
 		if (!pike_check_req())
 		{
 			xlog("L_ALERT","ALERT: pike blocking $rm from $fu (IP:$si:$sp)\n");
 			$sht(ipban=>$si) = 1;
 			exit;
 		}
 	}
 #!endif
 
 	if (!mf_process_maxfwd_header("10")) {
 		sl_send_reply("483","Too Many Hops");
 		exit;
 	}
 
 	if(!sanity_check("1511", "7"))
 	{
 		xlog("Malformed SIP message from $si:$sp\n");
 		exit;
 	}
 }
 
 # Handle requests within SIP dialogs
 route[WITHINDLG] {
 	if (has_totag()) {
 		# sequential request withing a dialog should
 		# take the path determined by record-routing
 		if (loose_route()) {
 			if (is_method("BYE")) {
 				setflag(FLT_ACC); # do accounting ...
 				setflag(FLT_ACCFAILED); # ... even if the transaction fails
 			}
 			route(RELAY);
 		} else {
 			if (is_method("SUBSCRIBE") && uri == myself) {
 				# in-dialog subscribe requests
 				route(PRESENCE);
 				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
 					t_relay();
 					exit;
 				} else {
 					# ACK without matching transaction ... ignore and discard
 					exit;
 				}
 			}
 			sl_send_reply("404","Not here");
 		}
 		exit;
 	}
 }
 
 # Handle SIP registrations
 route[REGISTRAR] {
 	if (is_method("REGISTER"))
 	{
 		if(isflagset(FLT_NATS))
 		{
 			setbflag(FLB_NATB);
 			# uncomment next line to do SIP NAT pinging 
 			## setbflag(FLB_NATSIPPING);
 		}
 		if (!save("location"))
 			sl_reply_error();
 
 		exit;
 	}
 }
 
 # USER location service
 route[LOCATION] {
 
 #!ifdef WITH_ALIASDB
 	# search in DB-based aliases
 	alias_db_lookup("dbaliases");
 #!endif
 
 	if (!lookup("location")) {
 		switch ($rc) {
 			case -1:
 			case -3:
 				t_newtran();
 				t_reply("404", "Not Found");
 				exit;
 			case -2:
 				sl_send_reply("405", "Method Not Allowed");
 				exit;
 		}
 	}
 
 	# when routing via usrloc, log the missed calls also
 	if (is_method("INVITE"))
 	{
 		setflag(FLT_ACCMISSED);
 	}
 }
 
 # Presence server route
 route[PRESENCE] {
 	if(!is_method("PUBLISH|SUBSCRIBE"))
 		return;
 
 #!ifdef WITH_PRESENCE
 	if (!t_newtran())
 	{
 		sl_reply_error();
 		exit;
 	};
 
 	if(is_method("PUBLISH"))
 	{
 		handle_publish();
 		t_release();
 	}
 	else
 	if( is_method("SUBSCRIBE"))
 	{
 		handle_subscribe();
 		t_release();
 	}
 	exit;
 #!endif
 	
 	# if presence enabled, this part will not be executed
 	if (is_method("PUBLISH") || $rU==$null)
 	{
 		sl_send_reply("404", "Not here");
 		exit;
 	}
 	return;
 }
 
 # Authentication route
 route[AUTH] {
 #!ifdef WITH_AUTH
 	if (is_method("REGISTER"))
 	{
 		# authenticate the REGISTER requests (uncomment to enable auth)
 		if (!www_authorize("$td", "subscriber"))
 		{
 			www_challenge("$td", "0");
 			exit;
 		}
 
 		if ($au!=$tU)
 		{
 			sl_send_reply("403","Forbidden auth ID");
 			exit;
 		}
 	} else {
 
 #!ifdef WITH_IPAUTH
 		if(allow_source_address())
 		{
 			# source IP allowed
 			return;
 		}
 #!endif
 
 		# authenticate if from local subscriber
 		if (from_uri==myself)
 		{
 			if (!proxy_authorize("$fd", "subscriber")) {
 				proxy_challenge("$fd", "0");
 				exit;
 			}
 			if (is_method("PUBLISH"))
 			{
 				if ($au!=$tU) {
 					sl_send_reply("403","Forbidden auth ID");
 					exit;
 				}
 			} else {
 				if ($au!=$fU) {
 					sl_send_reply("403","Forbidden auth ID");
 					exit;
 				}
 			}
 
 			consume_credentials();
 			# caller authenticated
 		} else {
 			# caller is not local subscriber, then check if it calls
 			# a local destination, otherwise deny, not an open relay here
 			if (!uri==myself)
 			{
 				sl_send_reply("403","Not relaying");
 				exit;
 			}
 		}
 	}
 #!endif
 	return;
 }
 
 # Caller NAT detection route
 route[NAT] {
 #!ifdef WITH_NAT
 	force_rport();
 	if (nat_uac_test("19")) {
 		if (method=="REGISTER") {
 			fix_nated_register();
 		} else {
 			fix_nated_contact();
 		}
 		setflag(FLT_NATS);
 	}
 #!endif
 	return;
 }
 
 # RTPProxy control
 route[RTPPROXY] {
 #!ifdef WITH_NAT
 	if (is_method("BYE")) {
 		unforce_rtp_proxy();
 	} else if (is_method("INVITE")){
 		force_rtp_proxy();
 	}
 	if (!has_totag()) add_rr_param(";nat=yes");
 #!endif
 	return;
 }
 
 # Routing to foreign domains
 route[SIPOUT] {
 	if (!uri==myself)
 	{
 		append_hf("P-hint: outbound\r\n");
 		route(RELAY);
 	}
 }
 
 # PSTN GW routing
 route[PSTN] {
 #!ifdef WITH_PSTN
 	# check if PSTN GW IP is defined
 	if (strempty($sel(cfg_get.pstn.gw_ip))) {
 		xlog("SCRIPT: PSTN rotuing enabled but pstn.gw_ip not defined\n");
 		return;
 	}
 
 	# route to PSTN dialed numbers starting with '+' or '00'
 	#     (international format)
 	# - update the condition to match your dialing rules for PSTN routing
 	if(!($rU=~"^(\+|00)[1-9][0-9]{3,20}$"))
 		return;
 
 	# only local users allowed to call
 	if(from_uri!=myself) {
 		sl_send_reply("403", "Not Allowed");
 		exit;
 	}
 
 	$ru = "sip:" + $rU + "@" + $sel(cfg_get.pstn.gw_ip);
 
 	route(RELAY);
 	exit;
 #!endif
 
 	return;
 }
 
 # XMLRPC routing
 #!ifdef WITH_XMLRPC
 route[XMLRPC]
 {
 	# allow XMLRPC from localhost
 	if ((method=="POST" || method=="GET")
 			&& (src_ip==127.0.0.1)) {
 		# close connection only for xmlrpclib user agents (there is a bug in
 		# xmlrpclib: it waits for EOF before interpreting the response).
 		if ($hdr(User-Agent) =~ "xmlrpclib")
 			set_reply_close();
 		set_reply_no_connect();
 		dispatch_rpc();
 		exit;
 	}
 	send_reply("403", "Forbidden");
 	exit;
 }
 #!endif
 
 # Sample branch router
 branch_route[BRANCH_ONE] {
 	xdbg("new branch at $ru\n");
 }
 
 # Sample onreply route
 onreply_route[REPLY_ONE] {
 	xdbg("incoming reply\n");
 #!ifdef WITH_NAT
 	if ((isflagset(FLT_NATS) || isbflagset(FLB_NATB))
 			&& status=~"(183)|(2[0-9][0-9])") {
 		force_rtp_proxy();
 	}
 	if (isbflagset(FLB_NATB)) {
 		fix_nated_contact();
 	}
 #!endif
 }
 
 # Sample failure route
 failure_route[FAIL_ONE] {
 #!ifdef WITH_NAT
 	if (is_method("INVITE")
 			&& (isbflagset(FLB_NATB) || isflagset(FLT_NATS))) {
 		unforce_rtp_proxy();
 	}
 #!endif
 
 	if (t_is_canceled()) {
 		exit;
 	}
 
 	# uncomment the following lines if you want to block client 
 	# redirect based on 3xx replies.
 	##if (t_check_status("3[0-9][0-9]")) {
 	##t_reply("404","Not found");
 	##	exit;
 	##}
 
 	# uncomment the following lines if you want to redirect the failed 
 	# calls to a different new destination
 	##if (t_check_status("486|408")) {
 	##	sethostport("192.168.2.100:5060");
 	##	append_branch();
 	##	# do not set the missed call flag again
 	##	t_relay();
 	##}
 }