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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Well, perhaps a bit more about my configuration 8-)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>3 nodes…call them N1, N2, N3.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>On each I have federation configured.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>N2 – exchange log, connects to N1/log and N3/log<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>N3 – exchange log, connects to N2/log<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Right now I cannot seem to have the N1 exchange log connect to N2/log; will need to find out why sometime.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I do it this way so that regardless of where the producer of the log message is, everyone everywhere will see it.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Each layer in the hierarchy only knows about nodes in adjacent layers…N2 being the busy one with a layer above and below.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>If everyone has hops=1, sending a log message to N1/log will only go to N2 and not N3 [this is correct].<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Setting hops=4, sending a log to N1/log will go to N2 and N3…it will also be returned to N2 thus a consumer on N2 will see the original msg AND the one sent via N2/N3 federation link. Also N3 sees it twice also for a total of once on N1, twice on N2, and twice on N3…the message took a total of 4 hops.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>So, this is what I mean by ‘one might expect’ 8-)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>-John<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Busoli, Simone [mailto:Simone.Busoli@ferrari.com] <br><b>Sent:</b> Tuesday, January 03, 2012 10:23 AM<br><b>To:</b> Letourneau, John P (John); rabbitmq-discuss@lists.rabbitmq.com<br><b>Subject:</b> RE: Federation Configuration and Duplicate Messages<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='color:#1F497D'>Hi John, I’m not sure about this:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'>As one might expect, this sometimes results in the message being seen >1 time at some clients.<o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>It shouldn’t be the expected behavior except for certain scenarios (i.e. disconnection of the brokers). Am I missing something perhaps?<o:p></o:p></span></p><p><span style='font-size:7.5pt'>_________________________________________________________________________________________________________________<br>Questo messaggio e da intendersi esclusivamente ad uso del destinatario e puo contenere informazioni che sono di natura privilegiata, confidenziale<br>o non divulgabile secondo le leggi vigenti. Se il lettore del presente messaggio non e il destinatario designato, o il dipendente/agente responsabile<br>per la consegna del messaggio al destinatario designato, si informa che ogni disseminazione, distribuzione o copiatura di questa comunicazione e <br>strettamente proibita anche ai sensi del decreto legislativo 196/03 . 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