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https://issues.apache.org/jira/browse/CLOUDSTACK-10305?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Nicolas Vazquez resolved CLOUDSTACK-10305.
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    Resolution: Fixed
      Assignee: Nicolas Vazquez

> Rare race condition in KVM migration
> ------------------------------------
>
>                 Key: CLOUDSTACK-10305
>                 URL: https://issues.apache.org/jira/browse/CLOUDSTACK-10305
>             Project: CloudStack
>          Issue Type: Bug
>      Security Level: Public(Anyone can view this level - this is the 
> default.) 
>            Reporter: Nicolas Vazquez
>            Assignee: Nicolas Vazquez
>            Priority: Major
>             Fix For: 4.11.1.0
>
>
> There is a race condition in the monitoring of the migration process on KVM. 
> If the monitor wakes up in the tight window after the migration succeeds, but 
> before the migration thread terminates, the monitor will get a 
> LibvirtException “Domain not found: no domain with matching uuid” when 
> checking on the migration status. This in turn causes CloudStack to sync the 
> VM state to stop, in which it issues a defensive StopCommand to ensure it is 
> correctly synced.
> This is issue is reported under these conditions:
>  * VM migration has physically finished
>  * Migration thread executor is still not marked as terminated
> From the migration monitoring process, as VM has been migrated, that domain 
> cannot be found (we should get the destination domain from the migration 
> thread later) and the LibvirtException is thrown: {{LibvirtException “Domain 
> not found: no domain with matching uuid”}}.
> So basically the idea is just logging the issue but not suspending the VM as 
> the migration has already been performed, but the migration thread is not 
> marked as finished. Once the migrarion thread is marked as finished, the 
> migration monitoring process (while loop) ends and the migration command 
> wrapper would continue its execution.
> Regarding your last question, we won't need to suspend the VM in this case as 
> the migration has already been performed. VM suspension will take place 
> whenever the migration is in progress and those conditions are met



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