Convert thick to thin don't works

[AslanovSergey]

Hello,

Please help me to find out why when i convert thick lazy zeroed disk to thin via vmkfstools -i ./disk.vmdk  ./thin-disk.vmdk -d thin, i get same thick lazy zeroed disk, although the process was going very well. 

[prasadsv]

Which version of ESX are you trying this. I couldn't see your issue. How did you confirm that the disk conversion didn't happen

[AslanovSergey]

ESXi 5.5. Doesn't issue when complete! I see that disk size on datastore stay same as it was. Similarly when I change disk in VM properties, the new disk remains same format (thick lazy zeroed).

[sajal1]

Why don't you try to do a storage migration, there you would get the option to convert it. Try this way and check. BY the way the command that you are giving would keep the disk.vmdk as it is and should create a new disk named thin-disk.vmdk, which should be thin disk. So what is the size and type of thin-disk.vmdk? Please confirm. Also if the thin-disk.vmdk is not in thin format then can you try to clone into any other datastore? Just for checking purpose.

[prasadsv]

Here is what i had:

1. What is the free space available on datastore before cloning the disk and after cloning the disk? If there is not change in the space then the disk created in a thin disk.

2. Which datastore are you using. If it NAS datastore,is it  a VAAI-NAS feature supported volume?

3. Did you observe the disk type as soon as it is created/cloned  from the command that you used or after attaching the disk to VM? Please observe the disk type before you attach the disk to VM(just after adding and before clicking "OK" radio button to complete the disk addition task) from UI and after attaching the disk(after clicking the "OK" radio button) in UI

[VSRawat]

After converting disk using vmkfstools command. Remove thick disk from VM's edit settings and add it as existing disk. Check vmdk it should be thin provision now.

[VSRawat]

After converting disk using vmkfstools command. Remove thick disk from VM's edit settings and add it as existing disk. Check vmdk it should be thin provision now. I remove thick vmdk from datastore.

After doing this I notice storage space is still same. I was expecting to free some space than I deleted flat file related to thick disk. Now I have free space.

These things are tested on VMDK which is running without snpashot. If your VM has snapshot than it can create problem.