Some one manually moved these vm's to different data store to bring them up and consolidate
When you are moving or cloning a snapshotted vms, the vmdks get consolidated.
In this process alost 90+ guest's vmx, vmdk and some other files were lost.
The vmdks will be consolidated as one, however, the vmx files SHOULD be there unless, some one manually deleted it or moved to another datastore.
is it netapp itself or human error.
Netapp will not do this unless, any scheduled tasks is kept.
Just to be sure, from the storage side, check if the lun mappings are still in tact and if any lun has been unmapped.
So I am trying to find the same in the logs, what caused the issue
Only vmkernel logs will be helpful to you on what happened, at what time, what process triggered it