Trying to use the dialog module to implement calllimits I'm running into a problem when trying to use keep-alives to detect dead dialogs. Limits work fine without keepalives. But as soon as either dlg_set_property("ka-dst"); or dlg_set_property("ka-src"); are used, after the ka_interval timeout kamailio will start to send OPTIONS as fast as possible. There is no difference in behavior for inbound of outbound calls. Older threads on this seem to end without solution. Increasing shmem/pkgmem makes no difference. System is running on Debian/stable with deb http://deb.kamailio.org/kamailio wheezy main packages. # kamailio -V version: kamailio 4.0.0 (x86_64/linux) flags: STATS: Off, USE_IPV6, USE_TCP, USE_TLS, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144, MAX_LISTEN 16, MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 4MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: unknown compiled on 13:13:24 Mar 29 2013 with gcc 4.7.2 modparam("dialog","dlg_flag",4) modparam("dialog","hash_size",4096) modparam("dialog","enable_stats",1) modparam("dialog","db_url",DBURL) modparam("dialog","db_mode", 2) modparam("dialog","db_update_period", 15) modparam("dialog","profiles_with_value","maxchannels") modparam("dialog","profiles_no_value", "all") modparam("dialog","dlg_match_mode", 1) modparam("dialog","send_bye", 1) modparam("dialog","default_timeout", 43200) modparam("dialog","ka_timer", 15) modparam("dialog","ka_interval", 30) dlm_manage() uses as: route[DIALOG] { if (is_method("CANCEL|ACK") || (has_totag() && is_method("INVITE| BYE"))) { dlg_manage(); return; } if (is_method("INVITE") && !has_totag()) { if($au==$null) { route(MAXCALLSINBOUND); } else { route(MAXCALLSOUTBOUND); } dlg_manage(); } } route[MAXCALLSOUTBOUND] { if(method=="INVITE") { if($au && $avp(src_maxchannels)>0) { $var(maxchannels) = 0; get_profile_size("maxchannels", "$au", "$var(maxchannels)"); if($var(maxchannels)>=$avp(src_maxchannels)) { send_reply("403","Call limit reached"); exit; } set_dlg_profile("maxchannels","$au"); dlg_set_property("ka-src"); get_profile_size("maxchannels", "$au", "$var(maxchannels)"); } } return; } MAXCALLSINBOUND is nearly the same but uses $rU instead of $au (and routes to voicemail/redirects if applicable). Resulting in network traffic: U +6.719318 10.0.32.42:5060 -> 10.0.34.226:27819 OPTIONS sip:+31880100781@10.0.34.226:27819 SIP/2.0. Via: SIP/2.0/UDP 10.0.32.42;branch=z9hG4bK3548.6baca897.0. To: sip:+31880100781@10.0.32.42;tag=3c64a586e73b0dc9o0. From: sip:0880100705@10.0.32.42;tag=as2b14090d. CSeq: 101 OPTIONS. Call-ID: db688a0a-53e2d315@localhost. Max-Forwards: 70. Content-Length: 0. . # U +0.000041 10.0.32.42:5060 -> 10.0.34.226:27819 OPTIONS sip:+31880100781@10.0.34.226:27819 SIP/2.0. Via: SIP/2.0/UDP 10.0.32.42;branch=z9hG4bK3548.7baca897.0. To: sip:+31880100781@10.0.32.42;tag=3c64a586e73b0dc9o0. From: sip:0880100705@10.0.32.42;tag=as2b14090d. CSeq: 101 OPTIONS. Call-ID: db688a0a-53e2d315@localhost. Max-Forwards: 70. Content-Length: 0. . # U +0.000028 10.0.32.42:5060 -> 10.0.34.226:27819 OPTIONS sip:+31880100781@10.0.34.226:27819 SIP/2.0. Via: SIP/2.0/UDP 10.0.32.42;branch=z9hG4bK3548.8baca897.0. To: sip:+31880100781@10.0.32.42;tag=3c64a586e73b0dc9o0. From: sip:0880100705@10.0.32.42;tag=as2b14090d. CSeq: 101 OPTIONS. Call-ID: db688a0a-53e2d315@localhost. Max-Forwards: 70. Content-Length: 0. . # U +0.000026 10.0.32.42:5060 -> 10.0.34.226:27819 OPTIONS sip:+31880100781@10.0.34.226:27819 SIP/2.0. Via: SIP/2.0/UDP 10.0.32.42;branch=z9hG4bK3548.9baca897.0. To: sip:+31880100781@10.0.32.42;tag=3c64a586e73b0dc9o0. From: sip:0880100705@10.0.32.42;tag=as2b14090d. CSeq: 101 OPTIONS. Call-ID: db688a0a-53e2d315@localhost. Max-Forwards: 70. Content-Length: 0. . [6412 more OPTIONS before hanging up or phone reboots] syslog output (another call since turning debug on will choke the machine in disk IO to syslog), it keeps repeating stuff like this: 14:19:56 DEBUG: topoh [topoh_mod.c:345]: the COOKIE is [xxx] 14:19:56 DEBUG: dialog [dlg_req_within.c:387]: keep-alive sent to caller 14:19:56 DEBUG: dialog [dlg_hash.c:753]: unref dlg 0x7fb4bfe3d2e0 with 1 -> 2 14:19:56 DEBUG: dialog [dlg_hash.c:588]: ref dlg 0x7fb4bfe3d2e0 with 1 -> 3 14:19:56 DEBUG: dialog [dlg_hash.c:590]: dialog id=7871 found on entry 2710 14:19:56 DEBUG: dialog [dlg_req_within.c:366]: sending BYE to caller 14:19:56 DEBUG: tm [uac.c:243]: DEBUG:tm:t_uac: next_hop=<sip: +31880100781@10.0.34.226:27819> 14:19:56 DEBUG: tm [uac.c:182]: DEBUG: dlg2hash: 6504 14:19:56 DEBUG: <core> [parser/msg_parser.c:623]: SIP Request: 14:19:56 DEBUG: <core> [parser/msg_parser.c:625]: method: <OPTIONS> 14:19:56 DEBUG: <core> [parser/msg_parser.c:627]: uri: <sip: +31880100781@10.0.34.226:27819> 14:19:56 DEBUG: <core> [parser/msg_parser.c:629]: version: <SIP/2.0> 14:19:56 DEBUG: <core> [parser/parse_via.c:1284]: Found param type 232, <branch> = <z9hG4bK8691.df660fd1.0>; state=16 14:19:56 DEBUG: <core> [parser/parse_via.c:2672]: end of header reached, state=5 14:19:56 DEBUG: <core> [parser/msg_parser.c:513]: parse_headers: Via found, flags=2 14:19:56 DEBUG: <core> [parser/msg_parser.c:515]: parse_headers: this is the first via 14:19:56 DEBUG: <core> [parser/parse_to.c:176]: DEBUG: add_param: tag=a2b76e7ff411361o0 14:19:56 DEBUG: <core> [parser/parse_to.c:799]: end of header reached, state=29 14:19:56 DEBUG: <core> [parser/msg_parser.c:190]: DEBUG: get_hdr_field: <To> [54]; uri=[sip:+31880100781@10.0.32.42] 14:19:56 DEBUG: <core> [parser/msg_parser.c:192]: DEBUG: to body [sip: +31880100781@109. 235.32.42] 14:19:56 DEBUG: <core> [parser/msg_parser.c:170]: get_hdr_field: cseq <CSeq>: <101> <OPTIONS> 14:19:56 DEBUG: <core> [parser/msg_parser.c:204]: DEBUG: get_hdr_body : content_length=0 14:19:56 DEBUG: <core> [parser/msg_parser.c:106]: found end of header 14:19:56 DEBUG: <core> [parser/parse_to.c:176]: DEBUG: add_param: tag=as23ba5e76 14:19:56 DEBUG: <core> [parser/parse_to.c:799]: end of header reached, state=29