Tool or a way to simulate overwriting of a lun?

[atle]

I am trying to grasp fractional reserve adn I am simulating this in my lab with a Windows machine connected to a iSCSI LUN on a Netapp.

How do I simulate overwriting a LUN? Because once the file system disk is full in my Windows disk, I cannot overwrite these blocks.

what I want to see is if I can overwrite as much as the fractional rserve is set at. My understanding is that if this is set at 50%, I can only overwrite 50% og the original LUN size.

[chriskranz]

You need to take a snapshot.

Write the volume full, then snapshot it, then remove and rewrite with fresh data. At this point, if you have set the fractional reservation to 50% and the volume size is thick provisioned at 150% of the LUN size, then you should run out of space! Depending on other factors, such as aggregate free space, will depend on how the LUN reacts to this.

[atle]

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[atle]

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[atle]

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