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<p class="MsoNormal">Hi Folks,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m trying to understand the configuration required to create a durable notification queue for billing with RabbitMQ.   As I understand it for messages to be durable there need to be three things:<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span><![endif]>The exchange has to be created as durable<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span><![endif]>The queue needs to be created as durable<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-18.0pt;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">-<span style="font:7.0pt "Times New Roman"">         
</span></span><![endif]>Messages themselves need to be marked as durable when they are published.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I can see that setting rabbit_durable_queues=True would create the exchange and notification publisher with the options required for me to create a durable queue for a billing system, but I thought there was a concern in having durable
 queues in general within Nova because if the consumer fails and recovers it may receive the same message multiple times  – so is there some magic in the system which prevents all of the other topic queues from becoming durable when this option is set (or is
 there no problem with durable queues in general) ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Cheers,<o:p></o:p></p>
<p class="MsoNormal">Phil<o:p></o:p></p>
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