<div dir="ltr"><div><div><div>Hello,<br><br></div>I have two opensip servers, exactly same configuration, but one is acting different. This is the call  flow. <br></div>Origination -- Invite------------&gt; Opensips<br></div>Origination &lt; 100 Trying ------ Opensips<br><div><div> ---------------------------------------Opensips ----invite --&gt; End user (freeswitch) <div>----------------------------------------Opensips &lt;--- 100 trying -- Freeswitch <br></div><div>----------------------------------------Opensips &lt;-- 183 Ringing -- Freeswitch<br></div><div>Keeps waiting and never forward 183 back to Origination. <br></div><div><br></div><div>While 2nd opensips works just fine/ <br></div><div><br></div><div>MTU is 1500 on both. <br></div><div>Working Server versions<br></div><div>Centos 5.2, Openisps 11-2<br><br></div><div>Not working, version (Different OS, same version of Opensips) <br></div><div>Cent OS 5.4, Opensips 11-2 <br></div><div><br></div><div>Below is the full trace. Any hint to fix this will big help. I am suspecting fragmented packet size in 183 Session Progress, but not sure how to fix it. If the packet is not fragmented all works fine. <br><br></div><div>This is original trace, ALL IPs has been modified for security. <br></div><div><br> <a href="http://15.43.72.36:5060">15.43.72.36:5060</a> -&gt; <a href="http://29.16.115.170:5060">29.16.115.170:5060</a><br>INVITE sip:+13033334444@domain.opensips.company.com:5060;user=phone;transport=UDP;maddr=29.16.115.170 SIP/2.0.<br>v: SIP/2.0/UDP 15.43.72.36:5060;branch=z9hG4bKa83557bc149a92c4dd2e82551235a4d3.35f93e16.<br>Record-Route: &lt;sip:15.43.72.36:5060;lr&gt;.<br>Remote-Party-ID: &lt;<a href="mailto:sip%3A%2B16784567634@52.88.1.5">sip:+16784567634@52.88.1.5</a>&gt;;screen=yes;party=calling;privacy=off.<br>f: &lt;sip:+16784567634@19.73.4.24:5060;user=phone&gt;;tag=-45026-1a697ef-67d2935e-1a697ef.<br>t: &lt;sip:+13033334444@52.88.1.5:5060;user=phone&gt;.<br>i: b3338bd0185eadc713c41a697ef72c17e921839f4f01a344bb8-0091-7406.<br>CSeq: 1 INVITE.<br>Allow: ACK,BYE,CANCEL,INVITE,OPTIONS,INFO,SUBSCRIBE,REFER,NOTIFY,PRACK.<br>v: SIP/2.0/UDP 52.88.1.5:5060;branch=z9hG4bK0cba239efe292bb148db0d60f1938f42.4937234e;received=52.88.1.5.<br>v: SIP/2.0/UDP IRW6:5060;maddr=19.73.4.24;branch=z9hG4bK-1a697ef-72c17e92-7809c98f;received=19.73.94.24.<br>Max-Forwards: 15.<br>m: &lt;sip:19.73.4.24:5060;transport=UDP&gt;.<br>k: 100rel, resource-priority, replaces.<br>c: application/sdp.<br>l: 235.<br>Record-Route: &lt;sip:52.88.1.5;lr&gt;.<br>.<br>v=0.<br>o=PVG 1453494628460 1453494628460 IN IP4 199.173.133.17.<br>s=-.<br>p=+1 6135555555.<br>c=IN IP4 199.173.133.17.<br>t=0 0.<br>m=audio 34552 RTP/AVP 18 0 8 101.<br>a=rtpmap:101 telephone-event/8000.<br>a=fmtp:101 0-15.<br>a=ptime:20.<br>a=fmtp:18 annexb=no.<br><br>#<br>U <a href="http://29.16.115.170:5060">29.16.115.170:5060</a> -&gt; <a href="http://15.43.72.36:5060">15.43.72.36:5060</a><br>SIP/2.0 100 Giving a try.<br>v: SIP/2.0/UDP 15.43.72.36:5060;branch=z9hG4bKa83557bc149a92c4dd2e82551235a4d3.35f93e16.<br>f: &lt;sip:+16784567634@19.73.4.24:5060;user=phone&gt;;tag=-45026-1a697ef-67d2935e-1a697ef.<br>t: &lt;sip:+13033334444@52.88.1.5:5060;user=phone&gt;.<br>i: b3338bd0185eadc713c41a697ef72c17e921839f4f01a344bb8-0091-7406.<br>CSeq: 1 INVITE.<br>v: SIP/2.0/UDP 52.88.1.5:5060;branch=z9hG4bK0cba239efe292bb148db0d60f1938f42.4937234e;received=52.88.1.5.<br>v: SIP/2.0/UDP IRW6:5060;maddr=19.73.4.24;branch=z9hG4bK-1a697ef-72c17e92-7809c98f;received=19.73.94.24.<br>Server: Opensips SIP Gateway.<br>Content-Length: 0.<br>.<br><br>#<br>U <a href="http://29.16.115.170:5060">29.16.115.170:5060</a> -&gt; <a href="http://28.3.8.20:5060">28.3.8.20:5060</a><br>INVITE sip:13033334444@28.3.8.20:5060;user=phone;transport=UDP SIP/2.0.<br>Record-Route: &lt;sip:29.16.115.170;lr;ftag=-45026-1a697ef-67d2935e-1a697ef;did=c63.65dae2a5&gt;.<br>Via: SIP/2.0/UDP 29.16.115.170:5060;branch=z9hG4bK3a79.ead0d7c5.0.<br>v: SIP/2.0/UDP 15.43.72.36:5060;branch=z9hG4bKa83557bc149a92c4dd2e82551235a4d3.35f93e16.<br>Record-Route: &lt;sip:15.43.72.36:5060;lr&gt;.<br>Remote-Party-ID: &lt;<a href="mailto:sip%3A%2B16784567634@52.88.1.5">sip:+16784567634@52.88.1.5</a>&gt;;screen=yes;party=calling;privacy=off.<br>f: &lt;sip:+16784567634@19.73.4.24:5060;user=phone&gt;;tag=-45026-1a697ef-67d2935e-1a697ef.<br>t: &lt;sip:+13033334444@52.88.1.5:5060;user=phone&gt;.<br>i: b3338bd0185eadc713c41a697ef72c17e921839f4f01a344bb8-0091-7406.<br>CSeq: 1 INVITE.<br>Allow: ACK,BYE,CANCEL,INVITE,OPTIONS,INFO,SUBSCRIBE,REFER,NOTIFY,PRACK.<br>v: SIP/2.0/UDP 52.88.1.5:5060;branch=z9hG4bK0cba239efe292bb148db0d60f1938f42.4937234e;received=52.88.1.5.<br>v: SIP/2.0/UDP IRW6:5060;maddr=19.73.4.24;branch=z9hG4bK-1a697ef-72c17e92-7809c98f;received=19.73.94.24.<br>Max-Forwards: 14.<br>m: &lt;sip:19.73.4.24:5060;transport=UDP&gt;.<br>k: 100rel, resource-priority, replaces.<br>c: application/sdp.<br>l: 235.<br>Record-Route: &lt;sip:52.88.1.5;lr&gt;.<br>.<br>v=0.<br>o=PVG 1453494628460 1453494628460 IN IP4 199.173.133.17.<br>s=-.<br>p=+1 6135555555.<br>c=IN IP4 199.173.133.17.<br>t=0 0.<br>m=audio 34552 RTP/AVP 18 0 8 101.<br>a=rtpmap:101 telephone-event/8000.<br>a=fmtp:101 0-15.<br>a=ptime:20.<br>a=fmtp:18 annexb=no.<br><br>#####<br>U <a href="http://28.3.8.20:5060">28.3.8.20:5060</a> -&gt; <a href="http://29.16.115.170:5060">29.16.115.170:5060</a><br>SIP/2.0 100 Trying.<br>Via: SIP/2.0/UDP 29.16.115.170:5060;branch=z9hG4bK3a79.ead0d7c5.0.<br>Via: SIP/2.0/UDP 15.43.72.36:5060;branch=z9hG4bKa83557bc149a92c4dd2e82551235a4d3.35f93e16.<br>Via: SIP/2.0/UDP 52.88.1.5:5060;branch=z9hG4bK0cba239efe292bb148db0d60f1938f42.4937234e;received=52.88.1.5.<br>Via: SIP/2.0/UDP IRW6:5060;maddr=19.73.4.24;branch=z9hG4bK-1a697ef-72c17e92-7809c98f;received=19.73.94.24.<br>Record-Route: &lt;sip:29.16.115.170;lr;ftag=-45026-1a697ef-67d2935e-1a697ef;did=c63.65dae2a5&gt;.<br>Record-Route: &lt;sip:15.43.72.36:5060;lr&gt;.<br>Record-Route: &lt;sip:52.88.1.5;lr&gt;.<br>From: &lt;sip:+16784567634@19.73.4.24:5060;user=phone&gt;;tag=-45026-1a697ef-67d2935e-1a697ef.<br>To: &lt;sip:+13033334444@52.88.1.5:5060;user=phone&gt;.<br>Call-ID: b3338bd0185eadc713c41a697ef72c17e921839f4f01a344bb8-0091-7406.<br>CSeq: 1 INVITE.<br>User-Agent: FreeSWITCH-mod_sofia/1.2.12+git~20130816T225403Z~8566ffa82a.<br>Content-Length: 0.<br>.<br><br>##########################<br>###############################<br>U <a href="http://28.3.8.20:5060">28.3.8.20:5060</a> -&gt; <a href="http://29.16.115.170:5060">29.16.115.170:5060</a><br>SIP/2.0 183 Session Progress.<br>Via: SIP/2.0/UDP 29.16.115.170:5060;branch=z9hG4bK3a79.ead0d7c5.0.<br>Via: SIP/2.0/UDP 15.43.72.36:5060;branch=z9hG4bKa83557bc149a92c4dd2e82551235a4d3.35f93e16.<br>Via: SIP/2.0/UDP 52.88.1.5:5060;branch=z9hG4bK0cba239efe292bb148db0d60f1938f42.4937234e;received=52.88.1.5.<br>Via: SIP/2.0/UDP IRW6:5060;maddr=19.73.4.24;branch=z9hG4bK-1a697ef-72c17e92-7809c98f;received=19.73.94.24.<br>Record-Route: &lt;sip:29.16.115.170;lr;ftag=-45026-1a697ef-67d2935e-1a697ef;did=c63.65dae2a5&gt;.<br>Record-Route: &lt;sip:15.43.72.36:5060;lr&gt;.<br>Record-Route: &lt;sip:52.88.1.5;lr&gt;.<br>From: &lt;sip:+16784567634@19.73.4.24:5060;user=phone&gt;;tag=-45026-1a697ef-67d2935e-1a697ef.<br>To: &lt;sip:+13033334444@52.88.1.5:5060;user=phone&gt;;tag=p5ZtZ40SSXprB.<br>Call-ID: b3338bd0185eadc713c41a697ef72c17e921839f4f01a344bb8-0091-7406.<br>CSeq: 1 INVITE.<br>Contact: &lt;sip:+13033334444@28.3.8.20:5060;transport=udp&gt;.<br>User-Agent: FreeSWITCH-mod_sofia/1.2.12+git~20130816T225403Z~8566ffa82a.<br>Accept: application/sdp.<br>Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, INFO, UPDATE, REGISTER, REFER, NOTIFY, PUBLISH, SUBSCRIBE.<br>Supported: timer, precondition, path, replaces.<br>Allow-Events: talk, hold, conference, presence, dialog, line-seize, call-info, sla, include-session-description, presence.winfo, message-summary, refer.<br>Content-Type: application/sdp.<br>Content-Disposition: session.<br>Content-Length: 249.<br>Remote-Party-ID: &quot;13033334444&quot; &lt;<a href="mailto:sip%3A13033334444@52.88.1.5">sip:13033334444@52.88.1.5</a>&gt;;party=calli<br># // Fragmented packet second part<br>U 28.3.8.20 -&gt; 29.16.115.170 +32125@1480:277<br>ng;privacy=off;screen=no.<br>.<br>v=0.<br>o=FreeSWITCH 1453563985 1453563986 IN IP4 28.3.8.20.<br>s=FreeSWITCH.<br>c=IN IP4 28.3.8.20.<br>t=0 0.<br>m=audio 21814 RTP/AVP 0 101.<br>a=rtpmap:0 PCMU/8000.<br>a=rtpmap:101 telephone-event/8000.<br>a=fmtp:101 0-16.<br>a=silenceSupp:off - - - -.<br>a=ptime:20.<br><br>#########################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################<br><br></div><div><br></div></div></div></div>