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I'm currently running ESX3.5 Update 4 in a development environment attached to a Netapp SAN, using NFS datastores.

I notice today that when I created a 20GB Virtual Machine, the Datastore only reported as to only approx 4GB being consumed, therefore I'm assuming it's being thin provisioned.

Is there a way of not thin provisioning?

Many thanks

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up vote 0 down vote accepted

Not by default but try defraging or disk-testing your guest-disks/vmdks from inside the guest, that's a good way of artificially 'blowing out' a thin to fat.

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From the man page to vmkfstools:

 -j, --inflatedisk
     Convert a thin virtual disk to preallocated with the additional
     guarantee that any data on thin disk is preserved and any blocks
     that were not allocated get allocated and zeroed out.
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From the 3.5U2 command ref "Note The only disk formats you can use for NFS are thin, thick, zerodthick and 2gbsparse. Thick, zeroedthick and thin usually mean the same because the NFS server and not the ESX Server host decides the allocation policy. The default allocation policy on most NFS servers is thin." – Chopper3 Jan 20 '10 at 15:00

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