1) When you delete "VMFS Datastore" - infact it does not do "Zero Fill" or "Wipe out" Full data bits on "Datastore"
2) You have 100% chance of recreating the same datastore (by recreating metadata & partition Geometry) - URL below recovers delted VMFS
www.demitasse.co.nz/wordpress2/2009/08/recovering-a-deleted-vmfs-datastore/
3) vmkfstools (having two sections a) VMFS files systems options b) VMDK disks commands for VM not (not VMFS commands)
the one you are referring "-w --writezeros" --> are not related to VMFS Filesystem commands (only limited VMDK disks of VM's)
4) Hence If you are looking at "Sensitivity of data like classified data" --> "-w --writezeros" --> will not help you
you need to do below to destroy the Data on "VMFS filesystem i.e Datastore" (even after deleting VMFS from VC)
CLI Method - vmkfstools -C vmfs3 -b 1m -S my_vmfs /vmfs/devices/disks/vml.vml_ID:1
GUI Method - Select ESX host on vSphere Client -> Configuration tab - Storage -> Add storage ->
choose the LUN ID you intend to destroy (be careful - this will destroy existing data on LU
Regards - Purna
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