Is it possible that the LUN will fill up before the datastore, thereby causing the LUN to offline? Answer is NO. The LUN contains exactly what VMware puts in the datastore. If VMFS thinks the file system is full, then the LUN is full. That may affect VMs depending on their config (thick vs. thin), but won’t take the LUN offline. What can take the LUN offline is space outside the LUN either in the volume (consumed by NetApp snapshots) or the aggr if the volume and LUN are thin provisioned.
The following TRs give detail information on these topics. TR-3749, 4068.
Hope this helps.
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