NS0-162 Exam Dumps : NetApp Certified Data Administrator (ONTAP)

The space allocation option is a LUN attribute that enables the host to communicate with the storage system about the blocks that are no longer in use by the host file system. When the space allocation option is enabled, the host sends SCSI UNMAP commands to the storage system when files are deleted on the disk. The storage system then reclaims the space from the thin-provisioned LUN and makes it available for other LUNs or volumes. This process is also known as space reclamation or hole punching. If the space allocation option is disabled, the host does not send SCSI UNMAP commands and the storage system does not reclaim the space from the thin-provisioned LUN, resulting in a discrepancy between the host and the storage system. References :- Space reclamation, Enable or disable the space allocation option for a LUN

The igroup is a logical grouping of initiators that can access a set of LUNs. The igroup must contain the IQNs (iSCSI Qualified Names) or WWPNs (World Wide Port Names) of the initiators that need to access the LUNs. In this scenario, the igroup named “ESX” has the iSCSI protocol and the VMware OS type, but it does not have any initiators listed. This means that the VMware hosts cannot authenticate and connect to the LUNs in the SVM. To resolve this issue, the igroup must be populated with the correct initiators that match the VMware hosts. This can be done by using the igroup add command or the System Manager GUI12. References :- Create an igroup, Add initiators to an igroup

The performance capacity report shows the current and optimal performance metrics for the CPU resource on each node of the cluster. The current metrics reflect the actual workload on the resource, while the optimal metrics reflect the workload that would result in the best performance. The performance capacity, or headroom, is the difference between the current and optimal metrics. A low or negative headroom indicates that the resource is over utilized and may experience performance degradation. The exhibit shows that both nodes have negative headroom for the CPU resource, which means that the CPU has been over utilized. A storage failover event will cause performance issues, as the surviving node will have to handle the workload of both nodes, which will further reduce the headroom and increase the latency. References :- Identify remaining performance capacity, What is Performance Capacity in ONTAP 9 and Unified Manager?