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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal>We are using RabbitMQ (version: 3.1.3) in federation mode on two different machines. We are using “rabbitmq-c” client library to publish messages to upstream broker, and right now we are not using confirm method or message persistence. But we want to achieve message reliability i.e. we don’t want to lose any messages. To achieve this, I am planning to use confirm method on publisher. I have following questions regarding the same:<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>If I get the confirmation acknowledgement, what does it mean? Is it message successfully delivered to “upstream queue” or “downstream exchange”?<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>If it guarantees delivery to “downstream exchange”, then do we need to use message persistence?<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>If confirmation means delivery to upstream queue, then, I think, it makes sense to use message persistence, right? If the upstream broker crashes, then without message persistence, messages in upstream queue will be lost, right?<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>How does message persistence work? How long messages are persisted on disk? Are they removed from disk when the consumer sends the acknowledgement?<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-family:Symbol'><span style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]>Or is there any other way to achieve message reliability? Any improvements or suggestions?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks in Advance,<o:p></o:p></p><p class=MsoNormal>Punit<o:p></o:p></p></div></body></html>