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Hi all,
I want to record a user's operation for later audit purpose. For
example, A user may start/reboot/shutdown a VM using nova command from
terminal or using the dashboard from browser.

How can I record this action and it's result to a log file(or some
other database) for later check? And I also want to do this for user's
operations in cinder and nova-network, such as creating a volume or
assigning a floating ip to a VM.

Is there any existing solution for this purpose? If not, where and how
should I start to do it myself by modifying the current nova's(or
cinder, nova-network) code?

Thank you very much!

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zym