Hi All.
Below is a snippet of an INVITE and you can see the usual "trying - your call is important to us" in the dialog. Anyhow, for some reason SER occasionally attempts to sent the ACK to itself, which causes a looping condition. The last ACK shown is the start of the looping condition.
It only happens on occasion. SER should have consumed the ACK rather than attempted to forward it.
Can anyone explain this?
Regards, Paul
IP Legend ------------------- 10.3.0.221 http://10.3.0.221 - SER (behind a Cisco 3600 so ALG rewrote the IPs) 69.36.46.178 http://69.36.46.178 - NATed SIP UA
U 2005/04/15 02:19:16.252614 69.35.46.178:5060 http://69.35.46.178:5060 -> 10.3.0.221:5060 http://10.3.0.221:5060 INVITE sip:8187768080@sipdev.mycompany.net SIP/2.0. Via: SIP/2.0/UDP 192.168.1.102:5060 http://192.168.1.102:5060 ;branch=z9hG4bK3915905414. From: Test User sip:3215591439@sipdev.mycompany.net;tag=1465261089. To: sip:8187768080@sipdev.mycompany.net. Call-ID: 2671219156@192.168.1.102. CSeq: 101 INVITE. Contact: sip:3215591439@192.168.1.102:5060. Proxy-Authorization: Digest username="3215591439", realm=" sipdev.mycompany.net http://sipdev.mycompany.net", nonce="425f5e0de25efdb3f5a6125dcf2147bf30fe9177", uri=" sip:8187768080@sipdev.mycompany.net", response="61996c3bdc10990fec7e245751777516", algorithm=MD5, cnonce="ae02e47a3355bada49ce344c92f48587", qop=auth, nc=00000002. max-forwards: 70. Allow: INVITE, ACK, CANCEL, BYE, REFER, NOTIFY. Content-Type: application/sdp. Content-Length: 180. . v=0. o=- 32014 3005 IN IP4 192.168.1.102 http://192.168.1.102. s=-. c=IN IP4 192.168.1.102 http://192.168.1.102. t=0 0. m=audio 13456 RTP/AVP 18 0 8 2 4 101. a=rtpmap:101 telephone-event/8000. a=fmtp:101 0-15. a=ptime:20. .
# U 2005/04/15 02:19:16.276216 10.3.0.221:5060 http://10.3.0.221:5060 -> 69.35.46.178:5060 http://69.35.46.178:5060 SIP/2.0 100 trying -- your call is important to us. Via: SIP/2.0/UDP 192.168.1.102:5060 http://192.168.1.102:5060 ;branch=z9hG4bK3915905414;rport=5060;received=69.35.46.178http://69.35.46.178 . From: Test User sip:3215591439@sipdev.mycompany.net;tag=1465261089. To: sip:8187768080@sipdev.myvox.net. Call-ID: 2671219156@192.168.1.102. CSeq: 101 INVITE. Content-Length: 0. .
# U 2005/04/15 02:19:16.792795 69.35.46.178:5060 http://69.35.46.178:5060 -> 10.3.0.221:5060 http://10.3.0.221:5060 ACK sip:8187768080@sipdev.mycompany.net SIP/2.0. Via: SIP/2.0/UDP 192.168.1.102:5060 http://192.168.1.102:5060 ;branch=z9hG4bK3499714875. From: Test User sip:3215591439@sipdev.mycompany.net;tag=1465261089. To: sip:8187768080@sipdev.mycompany.net;tag= cdbfe46960d7566fcbe09f199f2b328d.c2bb. Call-ID: 2671219156@192.168.1.102. CSeq: 100 ACK. Content-Length: 0. .
# U 2005/04/15 02:19:16.912146 10.3.0.221:5060 http://10.3.0.221:5060 -> 10.3.0.221:5060 http://10.3.0.221:5060 ACK sip:8187768080@sipdev.mycompany.net SIP/2.0. Max-Forwards: 10. Record-Route: <sip:10.3.0.221 http://10.3.0.221;ftag=1465261089;lr>. Via: SIP/2.0/UDP 10.3.0.221 http://10.3.0.221;branch=0. Via: SIP/2.0/UDP 192.168.1.102:5060 http://192.168.1.102:5060;received= 69.35.46.178 http://69.35.46.178;branch=z9hG4bK3499714875. From: Test User sip:3215591439@sipdev.mycompany.net;tag=1465261089. To: sip:8187768080@sipdev.mycompany.net;tag= cdbfe46960d7566fcbe09f199f2b328d.c2bb. Call-ID: 2671219156@192.168.1.102. CSeq: 100 ACK. Content-Length: 0. P-hint: Local Destination.