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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>I have Shibboleth SP setup in IIS protecting a website that connects to an InCommon IDP<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I keep getting requests for the same page every second or so from the same client IP.<o:p></o:p></p><p class=MsoNormal>Here is an example from the IIS log:<o:p></o:p></p><p class=MsoNormal>2015-08-04 15:50:40 IP_ADDRESS_REMOVED POST /Shibboleth.sso/SAML2/POST - 443 – IP_ADDRESS_REMOVED Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.1;+WOW64;+Trident/4.0;+SLCC2;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30729;+Media+Center+PC+6.0;+InfoPath.3;+.NET4.0C;+BRI/2;+.NET4.0E;+MS-RTC+LM+8) 200 0 0 224<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This will happen about once every 10 days or so and the same request will repeat every second for a couple of hours. This happens with different IP addresses and on different servers protected by Shibboleth SP. All of the servers are connecting to the same IDP however.<o:p></o:p></p><p class=MsoNormal>Today, the IP that this request came from was not accessing this server besides for this request. Last time this happened, I was seeing traffic from a different IP with both the repeated request and standard application usage. I talked to the user and the stated that everything seemed normal and they didn’t seem to hit any errors.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>In the shibd.log file it looks like a new session is successfully being create every time:<o:p></o:p></p><p class=MsoNormal>2015-08-04 16:37:48 INFO Shibboleth.SessionCache [48]: new session created: ID (_896939343b981b2c1b73d00638a34604) IdP (urn:mace:incommon:ucsf.edu) Protocol(urn:oasis:names:tc:SAML:2.0:protocol) Address (IP_ADDRESS_REMOVED)<o:p></o:p></p><p class=MsoNormal>2015-08-04 16:37:49 INFO Shibboleth.AttributeExtractor.XML [48]: skipping unmapped SAML 2.0 Attribute with Name: urn:oid:1.3.6.1.4.1.5923.1.1.1.5<o:p></o:p></p><p class=MsoNormal>2015-08-04 16:37:49 INFO Shibboleth.AttributeExtractor.XML [48]: skipping unmapped SAML 2.0 Attribute with Name: urn:oid:2.5.4.4<o:p></o:p></p><p class=MsoNormal>2015-08-04 16:37:49 INFO Shibboleth.AttributeExtractor.XML [48]: skipping unmapped SAML 2.0 Attribute with Name: urn:oid:2.5.4.42<o:p></o:p></p><p class=MsoNormal>2015-08-04 16:37:49 INFO Shibboleth.AttributeExtractor.XML [48]: skipping unmapped SAML 2.0 Attribute with Name: urn:oid:0.9.2342.19200300.100.1.3<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I ran Wireshark while it was happening, and there was the following error:<o:p></o:p></p><p class=MsoNormal>Source: Client’s desktop<o:p></o:p></p><p class=MsoNormal>Destination: Shibboleth SP Server<o:p></o:p></p><p class=MsoNormal>Protocol: TCP<o:p></o:p></p><p class=MsoNormal>Length: 804 <o:p></o:p></p><p class=MsoNormal>Info: [TCP Retransmission] 59913 -> 443 {PSH, ACK] Seq=118559 Ack=3325 Win=501 Len=750[Reassembly error, protocol TCP: New fragment overlaps old data (retransmission?)]<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Has anybody else hit something like this? I contacted the IDP team, but I was told that I misconfigured the Shibboleth SP and caused looping, however, I don’t understand if that’s valid or not, since this doesn’t always happen.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal>-Chris<o:p></o:p></p></div></body></html>