I'm in agreement with Randy's comment. Terms like snapshot, clone, duplicate, replicate, all have different meanings when looking under the covers. Some are misnomers while others are defining solutions in terms of defensible solutions. To be clear, more complete feature should have a definition of terms or a model that defines properties which differentiates the variations, something that can be described in the occi rendering format -gary Randy Bias wrote:
First off, we've got to be careful about saying 'copy the image'. You probably mean 'copy the instance'. Where an image is an on-disk representation of an unpowered VM and an instance is a running version of that same on-disk representation or a running copy.
So for 'cloning' do you mean:
- An image in a library is turned into an instance? - A running instance is copied? - If a running instance is copied do you have a new image or a new instance? - If you have a new instance, is it powered on automatically? - Does a new cloned instance have the exact same hardware profile as the original cloned instance? RAM, CPU, disk? - Does a cloned instance also duplicate the RAM?
In other words, am I making a PURE 100% duplicated running instance (there are use cases for this), a new reference image, or am I 'scaling' an instance (either horizontally with more copies or vertically with a bigger copy)?
I've seen clone used by customers, clouds, and various IT departments and I've almost never seen the same definition. It's about as bad as 'cloud' when it comes to being defined.
When our customers ask for cloning they also usually mean very different things.
I'd rather have a few different verbs here that specified different behavior and that's potentially a rat's nest because not every cloud supports all of these behaviors.
--Randy
On 5/7/09 12:44 AM, "Tino Vazquez" <tinova@fdi.ucm.es> wrote:
Hi Randy,
By "clone" I mean "copy the image" if set to yes or "use the original" if set to no. What other meaning do you have in mind?
Also, for me "stop" means stop the VM and dump the state onto a file. "suspend" would be stop it but keep the state in memory.
BTW, there is something in state machine diagram [1] that I still don't understand. The entry point (after start) I take it as the "defined" or "pending" state. If that is correct, then we have our VMs going always from the initial state to "suspended". Is that what we want?
Regards,
-Tino
[1]
http://forge.gridforum.org/sf/wiki/do/viewPage/projects.occi-wg/wiki/StateMode> l
-- Constantino Vázquez, Grid Technology Engineer/Researcher: http://www.dsa-research.org/tinova DSA Research Group: http://dsa-research.org Globus GridWay Metascheduler: http://www.GridWay.org OpenNebula Virtual Infrastructure Engine: http://www.OpenNebula.org
On Thu, May 7, 2009 at 1:29 AM, Randy Bias <randyb@gogrid.com> wrote:
dange