Helping Hand Questions for D-UN-DY-23

The snapshot option that is set automatically when a pool is configured is the Pool Automatic Deletion Policy. This option determines how the system handles the deletion of snapshots when the pool reaches a certain threshold of capacity utilization. The user can choose between three policies: Never Delete, Delete Oldest, or Delete LowestPriority. The Total Pool Consumption and the Snapshot Pool Consumption are not snapshot options, but rather metrics that show the amount of pool space consumed by the pool data and the snapshots respectively.

References: [Dell EMC Unity: Storage Pools and RAID Groups], [Dell EMC Unity: Snapshots and Thin Clones]

A LUN is a logical unit of storage that is presented to a host as a SCSI device. A LUN is composed of one or more RAID extents, which are the smallest units of storage that can be allocated to a LUN. A RAID extent is a slice of a RAID group that is used to store user data and parity information. The size of a RAID extent depends on the RAID type and the drive type of the RAID group. For example, a RAID 5 extent on a SAS drive is 128 MB, while a RAID 6 extent on a NL-SAS drive is 256 MB. The LUN is partitioned into slices that match the size of the RAID extents, and each slice is mapped to a RAID extent from a RAID group in the storage pool. The LUN slices are distributed across multiple RAID groups to improve performance and availability. References:

• Dell EMC Unity: Storage Pools and RAID Groups
• Dell EMC Unity: LUN Management

To apply the management IP from the vSphere UnityVSA console, the system administrator must use the svc_initial_config command. This command allows the user to configure the initial network settings for the UnityVSA, such as the management IP address, subnet mask, gateway, and DNS servers. The svc_ipmi command is used to configure the IPMI settings for the UnityVSA, such as the IPMI IP address, username, and password. The svc_change_hw_config command is used to change the hardware configuration of the UnityVSA, such as the number of CPU cores, memory size, and disk size. The svc_inject command is used to inject faults into the UnityVSA for testing purposes.

References: [Dell EMC UnityVSA Installation Guide], [Dell EMC UnityVSA Command Line Interface Reference Guide]