You are using thick provision lazy zeroed. If you want to have the space still left on the drive (as you posted in your first post, allocate 350GB but still see 450GB free you will need to use thin provision).
Thick Provision Lazy Zeroed works as following:
Creates a virtual disk in a default thick format. Space required for the virtual disk is allocated when the virtual disk is created. Data remaining on the physical device is not erased during creation, but is zeroed out on demand at a later time on first write from the virtual machine.
Using the default flat virtual disk format does not zero out or eliminate the possibility of recovering deleted files or restoring old data that might be present on this allocated space. You cannot convert a flat disk to a thin disk.
When you perform a "du" on the system you will indeed see only the used space but VMware ESXi calculates the space differently so you won't oversize your datastore.
Thin on the other hand will only allocate space when it is needed and "save" up before:
Use this format to save storage space. For the thin disk, you provision as much datastore space as the disk would require based on the value that you enter for the disk size. However, the thin disk starts small and at first, uses only as much datastore space as the disk needs for its initial operations.
For more information you can read up on it: http://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.vsphere.vm_admin.doc_50%2FGUID-4C0F4...
If you change to thin your problem will be resolved.
Hopefully this helps you further with your problem.
@nielsengelen - http://foonet.be - VCP4/5
