I have server with local drives and about 500GB LUN on some SAN storage. We recently attempted to P2V this server on to ESX but it would keep failing at 1% if the SAN storage was included but it would was successful without the SAN storage included and local drives only.

Any ideas guys? Thank you in advance for any help you are able to provide.

  • Why would you want to convert the SAN based disks as part of the machine conversion? If you need the data from the SAN why not create a new disk in the VM and restore the data from the SAN to it? – joeqwerty Mar 6 '11 at 19:41

Check the block size on the VMFS datastore that you're virtualizing to. A block size of 1MB (the default) has a maximum VMDK file size of 256GB; this would prevent a 500 GB disk from being created on that datastore.

If this is indeed the case, you'll need to switch to a larger block size. Unfortunately, reformatting the datastore is the only way to accomplish this.

For more info, VMware's KB covering block sizes is here.


Depending on the SAN - it may be presenting your ESX vmware environment with a Lot of unused space, but in the background over-commiting the free space. Can you check your SAN for available physical space?

Often times you have to build a bunch of zero'ed vmfs disks from the esxi console, then delete them. The SAN sees those as zero'ed and reclaims the space. I believe eagerzerodisk is a parameter.

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