Hello Dave,
"At when time/moment are the storage policy's applied."
When you create a VM the creation of the Objects (Namespace, .vmdk(s) and .vswp) is started immediately and based on the chosen Storage Policy (SP).
Thus if you created a VM with an FTT=1, SW=1 SP applied it will start creating 2 data components and a witness component for each Object.
"I don't want the situation that when I deploy a VM, after 5 minutes its removed because something failed but in the meantime VSAN is synchronizing the disk so its complianed with its SP."
If the VM is deleted, vSAN will not continue trying to resync this data - this is pretty similar to how it would work in VMFS-land if you deleted a VM as it was still creating it on datastore.
"Do I need a step created in between that have FTT=0 and after everything is finished, the right SP will be set OR does VSAN/VMWare applie a SP after a few minutes after deployment. If that's so can I change that time-window ?"
Not necessary, but if you want to set VM/Objects being created as FTT=0 then sure you can change the default SP applied or create new SPs that your script use on creation of VMs.
The SP is applied during Object creation as mentioned above.
Bob
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