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fordian
Hot Shot
Hot Shot

vmdk disk format

Hello,

When creating a new vmdk how can I see the disk format (zeroedthick or eagerzeroedthick or thick) on a vmfs3 volume ?

Thank you

Dominic

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6 Replies
oreeh
Immortal
Immortal

The default option is always zeroedthick.

If you want to create other disks you have to use vmkfstools.

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fordian
Hot Shot
Hot Shot

but how can I see the it after the creation of vmdks ?

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oreeh
Immortal
Immortal

You can only distinguish thin and thick disks (simply by looking at the size of the vmdk file).

I'm not aware of any method to distingish for example zeroed and eagerzeroed disks.

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fordian
Hot Shot
Hot Shot

I did not find anything.

I hope someone knows \!!!

Thank you

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oreeh
Immortal
Immortal

I just tried it

.

The only indication is

ddb.thinProvisioned = "1"

in the descriptor if it is a thin disk.

Eagerzeroed, zeroed and thick disks have the same descriptor.

Eagerzeroed and zeroed disks (of the same size) even pass a binary comparison.

Thick disks of course don't pass the binary comparison due to their nature.

The only logical answer to me is that part of the CID value distinguishes them.

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DonalB
Enthusiast
Enthusiast

Have been trying to find this out myself for a while, found this post http://communities.vmware.com/message/501161, which helps to some degree. Use the -s option with ls to see the block size so

ls -lh <vmdk path>

should show the size reported by the file and compare this to

ls -1sh <vmdk path>

and of it's smaller than the first value then it's a thin disk

Cheers

DB