Dell D-UN-DY-23 Online Practice Questions and Exam Preparation

Dell D-UN-DY-23 Online Questions & Answers

• Question 31:

  Into what size slices is the LUN partitioned for RAID extents?

  A. 256 MB
  B. 128 MB
  C. 64 MB
  D. 512MB
  B. 128 MB

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  Explanation/Reference:

  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

• Question 32:

  On a Dell Unity XT file system asynchronous replication session, how many system Snapshots are required to support replication?

  A. 4
  B. 8
  C. 2
  D. 1
  A. 4

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  Explanation/Reference:

  On a Dell Unity XT file system asynchronous replication session, four system Snapshots are required to support replication. Two system Snapshots are created on the source file system, and two system Snapshots are created on the destination file system. The source system Snapshots are used to track the changes that need to be replicated, and the destination system Snapshots are used to apply the changes and maintain a consistent point-in-time copy of the source data. The system Snapshots are automatically created and managed by the replication engine and are not visible to the user. References: [Dell EMC Unity: Replication Technologies], [Dell EMC Unity: File System Configuration]

• Question 33:

  Which I/O modules does the Unity 380/380F system support?

  A. 12 Gb/s SAS 2-Port 100 GbE
  B. 32 Gb/s Fibre Channel 10 GbE Base-T
  C. 12 Gb/s SAS 10 GbE Base-T
  D. 32 Gb/s Fibre Channel 2-Port 100 GbE
  C. 12 Gb/s SAS 10 GbE Base-T

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  Explanation/Reference:

  The Unity 380/380F system supports two types of I/O modules: 12 Gb/s SAS back-end and 10 GbE Base-T front-end. The 12 Gb/s SAS back-end module provides connectivity to the disk drives and expansion enclosures, while the 10 GbE Base-T front- end module provides network connectivity to the hosts and clients. The Unity 380/380F system has four I/O module slots, two for each SP. The 12 Gb/s SAS back-end module must be installed in slot 0 of each SP, and the 10 GbE Base-T front-end module can be installed in slot 1 of each SP. Therefore, the correct answer is C References: Dell EMC Unity: Hardware Information Guide Dell EMC Unity: Installation Guide

• Question 34:

  A deployment engineer has changed theSchedule Time Zoneunder the Settings menu. However, existing snapshots schedules continue to run at the previously configured time.

  Why is this occurring?

  A. Existing snapshot schedules cannot be updated to the same absolute time.
  B. The Unity system time is not set correctly and must be updated under system settings.
  C. Existing snapshot schedules are not updated to the same absolute time when the time zone is changed.
  D. The Unity management server was not restarted before time zone changes took effect.
  C. Existing snapshot schedules are not updated to the same absolute time when the time zone is changed.

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  Explanation/Reference:

  When the Schedule Time Zone is changed under the Settings menu, it only affects the display of the time zone and the creation of new snapshot schedules. Existing snapshot schedules are not automatically adjusted to the new time zone, and will continue to run at the same absolute time as before. For example, if a snapshot schedule was created to run every day at 10:00 AM inGMT+1, and the Schedule Time Zone was changed to GMT+2, the snapshot schedule will still run at 10:00 AM in GMT+1, which is

  11:00 AM in GMT+2. To update the existing snapshot schedules to the new time zone, the administrator must edit each schedule manually and change the start time accordingly. References: Dell EMC Unity: Snapshots and Thin Clones1, page 16.

• Question 35:

  What is a characteristic of FAST VP?

  A. Fast VP data relocation runs in the background at all times once it is enabled.
  B. Fast VP optimizes data replacement by moving 1 GB slices between disk tiers.
  C. Users can set the Fast VP data relocation rate.
  D. Users can enable or disable FAST VP at the LUN level.
  C. Users can set the Fast VP data relocation rate.

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  Explanation/Reference:

  FAST VP (Fully Automated Storage Tiering for Virtual Pools) is a feature that automatically moves data within a storage pool based on the performance requirements and access patterns of the data. FAST VP data relocation runs in the background according to a user-defined schedule and rate. The schedule determines when the data relocation starts and ends, and the rate determines how much system resources are used for the data relocation. Users can set the Fast VP data relocation rate to High, Medium, Low, or None. High means that the data relocation has the highest priority and uses the most system resources, while None means that the data relocation is disabled. Fast VP data relocation does not run at all times, but only during the scheduled window. Fast VP optimizes data placement by moving 256 MB slices between disk tiers, not 1 GB slices. Users cannot enable or disable FAST VP at the LUN level, but only at the storage pool level. References: [Dell EMC Unity: FAST Technology Overview], [Dell EMC Unity: Storage Pools and RAID Groups]

• Question 36:

  What is a characteristic of Host Groups?

  A. Access to block storage resources must be set before adding hosts to a host group.
  B. Block storage resources addedlo a host group are accessible to all the member hosts
  C. Hosts added to a host group must not have mapped block storage resources.
  D. Block storage resources attached to one of the member hosts are accessible to the entire host group.
  B. Block storage resources addedlo a host group are accessible to all the member hosts

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  Explanation/Reference:

  A characteristic of Host Groups is that block storage resources added to a host group are accessible to all the member hosts. A Host Group is a logical grouping of hosts that share the same access permissions and settings for block storage

  resources. By adding block storage resources to a host group, the user can simplify the management and allocation of storage for multiple hosts. Access to block storage resources does not need to be set before adding hosts to a host group,

  as the access permissions can be modified later. Hosts added to a host group can have mapped block storage resources, as long as they are not in conflict with the host group resources. Block storage resources attached to one of the

  member hosts are not accessible to the entire host group, unless they are also added to the host group.

  References: [Dell EMC Unity: Host Configuration], [Dell EMC Unity: Block Storage Provisioning]