[one-users] Beginner questions: Opennebula 2.2.1

[Steffen Neumann]

Hi, 

one add-on question:

On Fri, 2011-05-06 at 12:15 +0200, Tino Vazquez wrote:
...
> Shutdown represents a more clean approach, the VM is cleanly
> shut down, and the image saved if marked so.

Is that atomic ? Or under file locking control ?

If I have some place, say /srv/could/goldenimage/ubuntu.img
where my disk image file is stored, does shutdown then overwrite
the existing ubuntu.img, and what happens if during the XX seconds
of writing back a new VM is created from ubuntu.img ? 
Unless "save" is atomic, the new VM will fail on a half-written 
mix of old and new. Or did I miss anything ?
What happens if three VMs created off ubuntu.img shutdown 
simultanously ? Will each write its changes back 
into that single ubuntu.img ?

Yours,
Steffen

-- 
IPB Halle                    AG Massenspektrometrie & Bioinformatik
Dr. Steffen Neumann          http://www.IPB-Halle.DE
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