### Description

The kamailio 5.2.1 crashed

### Troubleshooting

pbx server sending INVITE to kamailio and kamailio prepare SIP packet for send to VOIP operator by domain kamailio tries to resolv the domain and in this time pbx server send to kamailio the CANCEL. kamailio canceling this dialog and after a while, it gives an error that the domain cannot be resolved and prepeare 478 answer for pbx server. But data for send is apsent and kamailio is segfailt

kamailio is started with option use_dns_cache=no

#### Reproduction

if the resolv of the domain direction occurs later than the cancel message for the current dialog

#### Debugging Data

``` GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-100.el7_4.1 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-redhat-linux-gnu". For bug reporting instructions, please see: http://www.gnu.org/software/gdb/bugs/... [New LWP 11633] Reading symbols from /usr/sbin/kamailio...Reading symbols from /usr/lib/debug/usr/sbin/kamailio.debug...done. done. Missing separate debuginfo for /usr/lib64/libcom_err.so.2 Try: yum --enablerepo='*debug*' install /usr/lib/debug/.build-id/a3/832734347dca522438308c9f08f45524c65c9b Missing separate debuginfo for Try: yum --enablerepo='*debug*' install /usr/lib/debug/.build-id/22/8adfe0d8c0852bf24f80b24803da9e25f5b21e [Thread debugging using libthread_db enabled] Using host libthread_db library "/usr/lib64/libthread_db.so.1". Core was generated by `/usr/sbin/kamailio -P /var/run/kamailio/kamailio.pid -f /etc/kamailio/kamailio.'. Program terminated with signal 11, Segmentation fault. #0 0x00007f47ff3bfbdf in _reply (trans=0x7f47016be920, p_msg=0x0, code=478, reason=0x7fffc8309960, lock=1) at t_reply.c:649 649 if (code>=180 && p_msg->to (gdb) set print pretty on (gdb) set print elements 0 (gdb) set height 0 (gdb) bt full #0 0x00007f47ff3bfbdf in _reply (trans=0x7f47016be920, p_msg=0x0, code=478, reason=0x7fffc8309960, lock=1) at t_reply.c:649 len = 135 buf = 0x80f7aa <__FUNCTION__.6461> "get_hdr_field" dset = 0x7f4800730ca8 "\001" bm = { to_tag_val = { s = 0x7fffc83099a0 "\001", len = 7009219 } } dset_len = 0 #1 0x00007f47ff3c7ae3 in t_reply (t=0x7f47016be920, p_msg=0x0, code=478, text=0x7fffc83099c0 "Unresolvable destination (478/TM)") at t_reply.c:1609 reason = { s = 0x7fffc83099c0 "Unresolvable destination (478/TM)", len = 33 } #2 0x00007f47ff40752f in kill_transaction (trans=0x7f47016be920, error=-478) at t_funcs.c:176 err_buffer = "Unresolvable destination (478/TM)\000\000\000\006\000\000\000\300\333+\371F\177\000\000\000\000\000\000\000\000\000\000.\001\000\000\000\240\232\060\310\377\177\000\000\324P#\371F\177\000\000\220ŀ\000\000\000\000\000R\270n\000\000\000\000\000`\232\060\310\377\177\000\000\210\037.\000H\177\000\000\211զ\000\000\000\000\000\rӦ\000\000\000\000" sip_err = 478 reply_ret = 5771 ret = 33 __FUNCTION__ = "kill_transaction" #3 0x00007f47ff380ed5 in t_unref (p_msg=0x7f48002e24f0) at t_lookup.c:1488 kr = REQ_ERR_DELAYED __FUNCTION__ = "t_unref" #4 0x00007f47ff41ccbc in w_t_unref (foo=0x7f48002e24f0, flags=2147483649, bar=0x0) at tm.c:684 No locals. #5 0x000000000055034d in exec_post_script_cb (msg=0x7f48002e24f0, type=REQUEST_CB_TYPE) at core/script_cb.c:182 cb = 0x7f4800289210 flags = 2147483649 __FUNCTION__ = "exec_post_script_cb" #6 0x00000000005cc77b in receive_msg ( buf=0xa6d1a0 <buf.6868> "INVITE sip:0972678971@y.y.y.y:5060 SIP/2.0\r\nVia: SIP/2.0/UDP x.x.x.x:5062;rport;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451\r\nFrom: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c\r\nTo: sip:0972678971@y.y.y.y\r\nContact: sip:asterisk@x.x.x.x:5062\r\nCall-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705\r\nCSeq: 20737 INVITE\r\nAllow: OPTIONS, SUBSCRIBE, NOTIFY, PUBLISH, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, REFER, MESSAGE\r\nSupported: 100rel, timer, replaces, norefersub\r\nSession-Expires: 1800\r\nMin-SE: 90\r\nX-SEND-TO-TRUNK: ukrteltrunk\r\nMax-Forwards: 69\r\nUser-Agent: Asterisk PBX 13.26.0\r\nContent-Type: application/sdp\r\nContent-Length: 284\r\n\r\nv=0\r\no=- 812296846 812296846 IN IP4 x.x.x.x\r\ns=Asterisk\r\nc=IN IP4 x.x.x.x\r\nt=0 0\r\nm=audio 16438 RTP/AVP 8 0 3 101\r\na=rtpmap:8 PCMA/8000\r\na=rtpmap:0 PCMU/8000\r\na=rtpmap:3 GSM/8000\r\na=rtpmap:101 telephone-event/8000\r\na=fmtp:101 0-16\r\na=ptime:20\r\na=maxptime:150\r\na=sendrecv\r\n", len=1001, rcv_info=0x7fffc830a120) at core/receive.c:362 msg = 0x7f48002e24f0 ctx = { rec_lev = 0, run_flags = 0, last_retcode = 1, jmp_env = {{ __jmpbuf = {783203822, 2071767658820475464, 4295072, 140736552019552, 0, 0, 2071767658933721672, -2071667646532085176}, __mask_was_saved = 0, __saved_mask = { __val = {0, 0, 0, 0, 0, 0, 0, 0, 0, 167503724544, 10998176, 140736552018216, 0, 55834574851, 783203822, 4295072} } }} } bctx = 0x0 ret = 0 stats_on = 0 tvb = { tv_sec = 0, tv_usec = 0 } tve = { tv_sec = 0, tv_usec = 0 } tz = { tz_minuteswest = 0, tz_dsttime = 0 } diff = 0 inb = { s = 0xa6d1a0 <buf.6868> "INVITE sip:0972678971@y.y.y.y:5060 SIP/2.0\r\nVia: SIP/2.0/UDP x.x.x.x:5062;rport;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451\r\nFrom: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c\r\nTo: sip:0972678971@y.y.y.y\r\nContact: sip:asterisk@x.x.x.x:5062\r\nCall-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705\r\nCSeq: 20737 INVITE\r\nAllow: OPTIONS, SUBSCRIBE, NOTIFY, PUBLISH, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, REFER, MESSAGE\r\nSupported: 100rel, timer, replaces, norefersub\r\nSession-Expires: 1800\r\nMin-SE: 90\r\nX-SEND-TO-TRUNK: ukrteltrunk\r\nMax-Forwards: 69\r\nUser-Agent: Asterisk PBX 13.26.0\r\nContent-Type: application/sdp\r\nContent-Length: 284\r\n\r\nv=0\r\no=- 812296846 812296846 IN IP4 x.x.x.x\r\ns=Asterisk\r\nc=IN IP4 x.x.x.x\r\nt=0 0\r\nm=audio 16438 RTP/AVP 8 0 3 101\r\na=rtpmap:8 PCMA/8000\r\na=rtpmap:0 PCMU/8000\r\na=rtpmap:3 GSM/8000\r\na=rtpmap:101 telephone-event/8000\r\na=fmtp:101 0-16\r\na=ptime:20\r\na=maxptime:150\r\na=sendrecv\r\n", len = 1001 } netinfo = { data = { s = 0xa6d1a0 <buf.6868> "INVITE sip:0972678971@y.y.y.y:5060 SIP/2.0\r\nVia: SIP/2.0/UDP x.x.x.x:5062;rport;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451\r\nFrom: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c\r\nTo: sip:0972678971@y.y.y.y\r\nContact: sip:asterisk@x.x.x.x:5062\r\nCall-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705\r\nCSeq: 20737 INVITE\r\nAllow: OPTIONS, SUBSCRIBE, NOTIFY, PUBLISH, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, REFER, MESSAGE\r\nSupported: 100rel, timer, replaces, norefersub\r\nSession-Expires: 1800\r\nMin-SE: 90\r\nX-SEND-TO-TRUNK: ukrteltrunk\r\nMax-Forwards: 69\r\nUser-Agent: Asterisk PBX 13.26.0\r\nContent-Type: application/sdp\r\nContent-Length: 284\r\n\r\nv=0\r\no=- 812296846 812296846 IN IP4 x.x.x.x\r\ns=Asterisk\r\nc=IN IP4 x.x.x.x\r\nt=0 0\r\nm=audio 16438 RTP/AVP 8 0 3 101\r\na=rtpmap:8 PCMA/8000\r\na=rtpmap:0 PCMU/8000\r\na=rtpmap:3 GSM/8000\r\na=rtpmap:101 telephone-event/8000\r\na=fmtp:101 0-16\r\na=ptime:20\r\na=maxptime:150\r\na=sendrecv\r\n", len = 1001 }, rcv = 0x7fffc830a120, dst = 0x0 } keng = 0x0 evp = { data = 0x7fffc8309ca0, rcv = 0x7fffc830a120, dst = 0x0 } cidlockidx = 0 cidlockset = 0 errsipmsg = 0 __FUNCTION__ = "receive_msg" #7 0x00000000004c8ad7 in udp_rcv_loop () at core/udp_server.c:541 len = 1001 buf = "INVITE sip:0972678971@y.y.y.y:5060 SIP/2.0\r\nVia: SIP/2.0/UDP x.x.x.x:5062;rport;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451\r\nFrom: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c\r\nTo: sip:0972678971@y.y.y.y\r\nContact: sip:asterisk@x.x.x.x:5062\r\nCall-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705\r\nCSeq: 20737 INVITE\r\nAllow: OPTIONS, SUBSCRIBE, NOTIFY, PUBLISH, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, REFER, MESSAGE\r\nSupported: 100rel, timer, replaces, norefersub\r\nSession-Expires: 1800\r\nMin-SE: 90\r\nX-SEND-TO-TRUNK: ukrteltrunk\r\nMax-Forwards: 69\r\nUser-Agent: Asterisk PBX 13.26.0\r\nContent-Type: application/sdp\r\nContent-Length: 284\r\n\r\nv=0\r\no=- 812296846 812296846 IN IP4 x.x.x.x\r\ns=Asterisk\r\nc=IN IP4 x.x.x.x\r\nt=0 0\r\nm=audio 16438 RTP/AVP 8 0 3 101\r\na=rtpmap:8 PCMA/8000\r\na=rtpmap:0 PCMU/8000\r\na=rtpmap:3 GSM/8000\r\na=rtpmap:101 telephone-event/8000\r\na=fmtp:101 0-16\r\na=ptime:20\r\na=maxptime:150\r\na=sendrecv\r\n\000\070\060\060\060\r\na=rtpmap:3 GSM/8000\r\na=rtpmap:101 telephone-event/8000\r\na=fmtp:101 0-16\r\na=ptime:20\r\na=maxptime:150\r\na=sendrecv\r\n\000AVP 8 0 3 101\r\na=rtpmap:8 PCMA/8000\r\na=rtpmap:0 PCMU/8000\r\na=rtpmap:3 GSM/8000\r\na=rtpmap:101 telephone-event/8000\r\na=fmtp:101 0-16\r\na=ptime:20\r\na=maxptime:150\r\na=sendrecv\r\n\000yes\r\na=rtpmap:98 telephone-event/8000\r\na=fmtp:98 0-15\r\na=ptime:20\r\na=sendrecv\r\n\000\n\000vent/8000\r\na=fmtp:98 0-15\r\na=ptime:20\r\na=sendrecv\r\n\000\r\na=ptime:20\r\na=sendrecv\r\n", '\000' <repeats 64080 times> tmp = 0xa7d1a0 <buff.5595> "188.163.212.3" from = 0x7f47ffb77c20 fromlen = 16 ri = { src_ip = { af = 2, len = 4, u = { addrl = {870309723, 140736552018432}, addr32 = {870309723, 0, 3358630400, 32767}, addr16 = {57179, 13279, 0, 0, 41472, 51248, 32767, 0}, addr = "[\337\337\063\000\000\000\000\000\242\060\310\377\177\000" } }, dst_ip = { af = 2, len = 4, u = { addrl = {1510032313, 0}, addr32 = {1510032313, 0, 0, 0}, addr16 = {17337, 23041, 0, 0, 0, 0, 0, 0}, addr = "\271C\001Z", '\000' <repeats 11 times> } }, src_port = 5062, dst_port = 5060, proto_reserved1 = 0, proto_reserved2 = 0, src_su = { s = { sa_family = 2, sa_data = "\023\306[\337\337\063\000\000\000\000\000\000\000" }, sin = { sin_family = 2, sin_port = 50707, sin_addr = { s_addr = 870309723 }, sin_zero = "\000\000\000\000\000\000\000" }, sin6 = { sin6_family = 2, sin6_port = 50707, sin6_flowinfo = 870309723, sin6_addr = { __in6_u = { __u6_addr8 = '\000' <repeats 15 times>, __u6_addr16 = {0, 0, 0, 0, 0, 0, 0, 0}, __u6_addr32 = {0, 0, 0, 0} } }, sin6_scope_id = 0 } }, bind_address = 0x7f47ffb76bb0, proto = 1 '\001' } evp = { data = 0x0, rcv = 0x0, dst = 0x0 } printbuf = '\000' <repeats 17 times>, "\273}\000\000\000\000\000\326\301b\312|\000\000\000\344\034~\000\000\000\000\000V\274}\000\000\000\000\000\060\000\000\000\000\000\000\000\020`\255\377G\177\000\000\000\000\000\000\024\000\000\000\240Qx", '\000' <repeats 13 times>, "\264Qx\000\000\000\000\000.\000\000\000\000\240\211A\000\000\000\000\000\240\237\060\310\377\177\000\000\354\315c\000\000\000\000\000Xw\267\377G\177\000\000\220\241\262", '\000' <repeats 17 times>, "\004\000\000\000@\240\060\310\377\177\000\000P\326c\000\000\000\000\000\177", '\000' <repeats 15 times>, "\002", '\000' <repeats 19 times>, "\024\000\000\000\240Qx", '\000' <repeats 13 times>, "\200\241\262\000\n\000\000\000\240Qx\000\000\000\000\000\200\241\262\000\000\000\000\000@\240\060\310\377\177\000\000Xw\267\377G\177\000\000\000\000\000\000\000\000\000\000.\000\000\000\000\240\211A\000\000\000\000\000`\246\060\310\377\177", '\000' <repeats 18 times>, "p\240\060\310\377\177\000\000d\341c\000\000\000\000\000\240Qx\000\000\000\000\000\200\241\262", '\000' <repeats 13 times>, "\024\000\000\000\n\000\000\000\000\242\060\310\377\177\000\000H}J\000\000\000\000\000\240\211A\000\000\000\000\000`\246\060\310\377\177", '\000' <repeats 19 times>, "\241\060\310\377\177\000\000\yq\000\001\000\000\000\240Qx\000\000\000\000\000\024\000\000\000G\177\000\000\000\000\000\000\000\000\000\000$B\262\000\000\000\000\000$F\262\000\000\000\000\000\\022\001\377F\177\000\000\240\211A\000\000\000\000\000`\246\060\310\377\177", '\000' <repeats 17 times> i = 10 j = 4776853 l = 1178866774 __FUNCTION__ = "udp_rcv_loop" #8 0x0000000000424e5c in main_loop () at main.c:1645 i = 0 pid = 0 si = 0x7f47ffb76bb0 si_desc = "udp receiver child=0 sock=y.y.y.y:5060\000\000H\177\000\000\260\242\060\310\377\177\000\000\371\233h\000\000\000\000\000\240\211A\000\000\000\000\000\310F\264\376F\177", '\000' <repeats 14 times>, "\001\000\000\000\000\243\060\310\377\177\000\000(&\001\377F\177\000\000\310\064\020\367F\177\000\000\260Z\374\377G\177\000" nrprocs = 8 woneinit = 0 __FUNCTION__ = "main_loop" #9 0x000000000042c4e9 in main (argc=13, argv=0x7fffc830a668) at main.c:2675 cfg_stream = 0xdce010 c = -1 r = 0 tmp = 0x7fffc830af30 "" tmp_len = 0 port = 0 proto = 0 options = 0x7697a0 ":f:cm:M:dVIhEeb:l:L:n:vKrRDTN:W:w:t:u:g:P:G:SQ:O:a:A:x:X:Y:" ret = -1 seed = 995796597 rfd = 4 debug_save = 0 debug_flag = 0 dont_fork_cnt = 0 n_lst = 0x0 p = 0x0 st = { st_dev = 19, st_ino = 54007, st_nlink = 2, st_mode = 16832, st_uid = 989, st_gid = 987, __pad0 = 0, st_rdev = 0, st_size = 40, st_blksize = 4096, st_blocks = 0, st_atim = { tv_sec = 1558706870, tv_nsec = 104275123 }, st_mtim = { tv_sec = 1598532057, tv_nsec = 575105503 }, st_ctim = { tv_sec = 1598532057, tv_nsec = 575105503 }, __unused = {0, 0, 0} } __FUNCTION__ = "main" (gdb) info locals cfg_stream = 0xdce010 c = -1 r = 0 tmp = 0x7fffc830af30 "" tmp_len = 0 port = 0 proto = 0 options = 0x7697a0 ":f:cm:M:dVIhEeb:l:L:n:vKrRDTN:W:w:t:u:g:P:G:SQ:O:a:A:x:X:Y:" ret = -1 seed = 995796597 rfd = 4 debug_save = 0 debug_flag = 0 dont_fork_cnt = 0 n_lst = 0x0 p = 0x0 st = { st_dev = 19, st_ino = 54007, st_nlink = 2, st_mode = 16832, st_uid = 989, st_gid = 987, __pad0 = 0, st_rdev = 0, st_size = 40, st_blksize = 4096, st_blocks = 0, st_atim = { tv_sec = 1558706870, tv_nsec = 104275123 }, st_mtim = { tv_sec = 1598532057, tv_nsec = 575105503 }, st_ctim = { tv_sec = 1598532057, tv_nsec = 575105503 }, __unused = {0, 0, 0} } __FUNCTION__ = "main" (gdb) list 644 if (dset) { 645 add_lump_rpl(p_msg, dset, dset_len, LUMP_RPL_HDR); 646 } 647 } 648 649 if (code>=180 && p_msg->to 650 && (get_to(p_msg)->tag_value.s==0 651 || get_to(p_msg)->tag_value.len==0)) { 652 calc_crc_suffix( p_msg, tm_tag_suffix ); 653 buf = build_res_buf_from_sip_req(code, reason, &tm_tag, p_msg, (gdb) frame 0 #0 0x00007f47ff3bfbdf in _reply (trans=0x7f47016be920, p_msg=0x0, code=478, reason=0x7fffc8309960, lock=1) at t_reply.c:649 649 if (code>=180 && p_msg->to (gdb) info locals len = 135 buf = 0x80f7aa <__FUNCTION__.6461> "get_hdr_field" dset = 0x7f4800730ca8 "\001" bm = { to_tag_val = { s = 0x7fffc83099a0 "\001", len = 7009219 } } dset_len = 0 (gdb) p p_msg $1 = (struct sip_msg *) 0x0 (gdb) p p_msg->to Cannot access memory at address 0xa0 ```

#### Log Messages

``` Aug 28 14:09:45 ua1api [11633]: NOTICE: d03a799f-bb2a-4dc1-864a-b80d82d38705 -=> INCOMING REQUEST: method:INVITE si:x.x.x.x sp:5062 fU:380674606869 => rU:0972678971 proto:udp fu:sip:380674606869@x.x.x.x => ru:sip:0972678971@1 85.67.1.90:5060 ... Aug 28 14:09:51 ua1api [11654]: NOTICE: d03a799f-bb2a-4dc1-864a-b80d82d38705 -=> INCOMING REQUEST: method:CANCEL si:x.x.x.x sp:5062 fU:380674606869 => rU:0972678971 proto:udp fu:sip:380674606869@x.x.x.x => ru:sip:0972678971@y.y.y.y:5060 ... Aug 28 14:10:05 ua1api [11633]: ERROR: <core> [core/resolve.c:1685]: sip_hostport2su(): could not resolve hostname: "sip-trunk.ukrtelecom.ua" Aug 28 14:10:05 ua1api [11633]: ERROR: tm [ut.h:309]: uri2dst2(): failed to resolve "sip-trunk.ukrtelecom.ua" Aug 28 14:10:05 ua1api [11633]: ERROR: tm [t_fwd.c:1735]: t_forward_nonack(): failure to add branches Aug 28 14:10:05 ua1api [11633]: NOTICE: d03a799f-bb2a-4dc1-864a-b80d82d38705 -=> T_RELAY: result: -478 Aug 28 14:13:25 ua1api [11680]: CRITICAL: <core> [core/pass_fd.c:277]: receive_fd(): EOF on 15 Aug 28 14:13:25 ua1api [11605]: ALERT: <core> [main.c:756]: handle_sigs(): child process 11633 exited by a signal 11 Aug 28 14:13:25 ua1api [11605]: ALERT: <core> [main.c:759]: handle_sigs(): core was generated ```

#### SIP Traffic

``` <--- size: 1100 -- SIP from: UDP:x.x.x.x:5062 => to: UDP:y.y.y.y:5060 ---> INVITE sip:0972678971@y.y.y.y:5060 SIP/2.0 Via: SIP/2.0/UDP x.x.x.x:5062;rport;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451 From: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c To: sip:0972678971@y.y.y.y Contact: sip:asterisk@x.x.x.x:5062 Call-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705 CSeq: 20737 INVITE Allow: OPTIONS, SUBSCRIBE, NOTIFY, PUBLISH, INVITE, ACK, BYE, CANCEL, UPDATE, PRACK, REGISTER, REFER, MESSAGE Supported: 100rel, timer, replaces, norefersub Session-Expires: 1800 Min-SE: 90 X-SEND-TO-TRUNK: ukrteltrunk Max-Forwards: 70 User-Agent: Asterisk PBX 13.26.0 Content-Type: application/sdp Content-Length: 284

v=0 o=- 812296846 812296846 IN IP4 x.x.x.x s=Asterisk c=IN IP4 x.x.x.x t=0 0 m=audio 16438 RTP/AVP 8 0 3 101 a=rtpmap:8 PCMA/8000 a=rtpmap:0 PCMU/8000 a=rtpmap:3 GSM/8000 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-16 a=ptime:20 a=maxptime:150 a=sendrecv

<--- size: 493 -- SIP from: UDP:y.y.y.y:5060 => to: UDP:x.x.x.x:5062 ---> SIP/2.0 100 Trying -- your call is important to us Via: SIP/2.0/UDP x.x.x.x:5062;rport=5062;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451;received=x.x.x.x From: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c To: sip:0972678971@y.y.y.y Call-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705 CSeq: 20737 INVITE Content-Length: 0

<--- size: 537 -- SIP from: UDP:x.x.x.x:5062 => to: UDP:y.y.y.y:5060 ---> CANCEL sip:0972678971@y.y.y.y:5060 SIP/2.0 Via: SIP/2.0/UDP x.x.x.x:5062;rport;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451 From: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c To: sip:0972678971@y.y.y.y Call-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705 CSeq: 20737 CANCEL Reason: Q.850;cause=0 Max-Forwards: 70 User-Agent: Asterisk PBX 13.26.0 Content-Length: 0

<--- size: 404 -- SIP from: UDP:y.y.y.y:5060 => to: UDP:x.x.x.x:5062 ---> SIP/2.0 487 Request canceled Via: SIP/2.0/UDP x.x.x.x:5062;rport=5062;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451;received=x.x.x.x From: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c To: sip:0972678971@y.y.y.y;tag=29c79435251d3407255ea131eaa41394-e324 Call-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705 CSeq: 20737 INVITE Content-Length: 0

<--- size: 418 -- SIP from: UDP:y.y.y.y:5060 => to: UDP:x.x.x.x:5062 ---> SIP/2.0 200 ok -- no more pending branches Via: SIP/2.0/UDP x.x.x.x:5062;rport=5062;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451;received=x.x.x.x From: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c To: sip:0972678971@y.y.y.y;tag=29c79435251d3407255ea131eaa41394-e324 Call-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705 CSeq: 20737 CANCEL Content-Length: 0

<--- size: 550 -- SIP from: UDP:x.x.x.x:5062 => to: UDP:y.y.y.y:5060 ---> ACK sip:0972678971@y.y.y.y:5060 SIP/2.0 Via: SIP/2.0/UDP x.x.x.x:5062;rport;branch=z9hG4bKPjcf4a2178-296c-40ac-99e1-0e038f278451 From: "380674606869" sip:380674606869@x.x.x.x;tag=238ff2c1-ef95-4064-8541-c6e413343f3c To: sip:0972678971@y.y.y.y;tag=29c79435251d3407255ea131eaa41394-e324 Call-ID: d03a799f-bb2a-4dc1-864a-b80d82d38705 CSeq: 20737 ACK Max-Forwards: 70 User-Agent: Asterisk PBX 13.26.0 Content-Length: 0 ```

### Additional Information

* **Kamailio Version** - output of `kamailio -v`

``` version: kamailio 5.2.1 (x86_64/linux) flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS, DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, 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_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB poll method support: poll, epoll_lt, epoll_et, sigio_rt, select. id: compiled on 11:49:01 Jan 30 2019 with gcc 4.8.5 ```

* **Operating System**:

``` CentOS Linux release 7.4.1708 (Core) Linux ua1api.ringostat.net 3.10.0-693.21.1.el7.x86_64 #1 SMP Wed Mar 7 19:03:37 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux ```