I found out that this issue was exactly mentioned in the ESXi 5.0 Release Note.So, it wasn’t EMC plug-in's issue, it’s VMware issue (bug?).  ESXi cannot distinguish between thick provision lazy zeroed and thick provision eager zeroed virtual disks on NFS datastores with Hardware Acceleration support When you use NFS datastores that support Hardware Acceleration, the vSphere Client allows you to create virtual disks in Thick Provision Lazy Zeroed (zeroedthick) or Thick Provision Eager Zeroed (eagerzeroedthick) format. However, when you check the disk type on the Virtual Machine Properties dialog box, the Disk Provisioning section always shows Thick Provision Eager Zeroed as the disk format no matter which format you selected during the disk creation. ESXi does not distinguish between lazy zeroed and eager zeroed virtual disks on NFS datastores.    [URL]  Motoo Ichikawa
Hi all,  Does anybody have tried a thick (lazy zeroed) provisioning using NFS VAAI?  I’ve got somewhat urgent question from my customer. I’ve done some testing by myself and came out with the same result.  Would anybody please advise me whether there is some known bug for this or with any other comment? Any advice would be very very appreciated.   I’m wondering whether this is just a display issue or might be a critically issue that lazy zeroed provisioning is not working properly…  Thank you in advance and best regards!      ----------------------------------   Motoo Ichikawa   EMC Japan   vSpecialist Sr. Technology Consultant   Motoo.Ichikawa[NAME].com   --------------------------------- 
Lazy Zeroed Provisioning on NFS VAAI