Pass the Netapp NCIE SAN ONTAP NS0-522 Questions and answers with CertsForce

After deleting a LUN, if the space does not show as available, performing space reclamation is necessary. Space reclamation involves identifying and reclaiming unused space on the storage system, making it available for new data. This process ensures that the deleted LUN ' s space is properly freed up and reflected in the available storage capacity.

For more details, refer to:

NetApp Documentation on Space Reclamation

NetApp Community on Free Space Reclamation

The correct available capacity is 20 GB. Both 20 GB LUNs are space-reserved, so ONTAP reserves their full provisioned capacity rather than only the 10 GB currently consumed in each LUN. The two LUN reservations therefore account for 40 GB. Because the volume uses a 100% fractional reserve and a Snapshot copy exists, ONTAP also reserves sufficient overwrite space for 100% turnover of the reserved objects. That represents another 40 GB. Consequently, 80 GB of the 100 GB volume is committed: 40 GB for the two space-reserved LUNs and 40 GB to guarantee their overwrites. This leaves 20 GB available. NetApp describes fractional reserve 100 as reserving 100% of the space necessary for overwrites of reserved objects. Relevant topics include LUN space reservation, fractional reserve, thick provisioning, and Snapshot overwrite guarantees.