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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I would like to collect some thoughts for fixing LP bug: <a href="https://bugs.launchpad.net/nova/+bug/957009">
https://bugs.launchpad.net/nova/+bug/957009</a>.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Following is the scenario:<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">1.<span style="font:7.0pt "Times New Roman"">      
</span></span><![endif]>The Compute service hosting an active instance goes down and user requests DELETE operation on that instance.<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">2.<span style="font:7.0pt "Times New Roman"">      
</span></span><![endif]>The Nova API finds the Compute service running (since it had updated heartbeat recently than ‘service_down_time’ period). It marks the instance task_state as DELETING and casts a delete to the Compute.<o:p></o:p></p>
<p class="MsoListParagraph" style="text-indent:-.25in;mso-list:l0 level1 lfo1"><![if !supportLists]><span style="mso-list:Ignore">3.<span style="font:7.0pt "Times New Roman"">      
</span></span><![endif]>If the RabbitMQ service happens to restart before the Compute service comes up, the DELETE message to Compute will be lost and the instance will remain in DELETING state (vm_state=ACTIVE, task_state=DELETING, power_state=1). Also, even
 the ‘_cleanup_running_deleted_instances’ periodic task won’t clean up such instance.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Solution:<o:p></o:p></p>
<p class="MsoNormal">I am planning to add a periodic task to Nova Compute similar to the ‘_check_instance_build_time’ periodic task, which will poll for instances in ‘DELETING’ state for some configurable value and set them to ERROR state.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Suggestions are welcome.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Thanks & Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Unmesh Gurjar</span></b><span style="font-size:10.0pt;font-family:"Arial","sans-serif""> | Lead Engineer |
</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">NTT DATA Global Technology Services Private Limited |
<b>w.</b> +91.20.6604.1500 x 379 | <b>m.</b> +91.982.324.7631 | <span style="color:black">
<a href="mailto:unmesh.gurjar@nttdata.com">unmesh.gurjar@nttdata.com</a> | </span>
</span><span style="font-size:10.0pt;font-family:"Arial","sans-serif"">Learn more at nttdata.com/americas<b><o:p></o:p></b></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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