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

• Question 11:

  In an asynchronous replication, what is the maximum number of replicated NAS servers supported for the Dell Unity XT 380 series?

  A. 64

  B. 90

  C. 126

  D. 256

  Correct Answer: C

  The maximum number of replicated NAS servers supported for the Dell Unity XT 380 series in an asynchronous replication is 126. This is the same as the maximum number of NAS servers supported for the Dell Unity XT 380 series in

  general. Asynchronous replication is a method of replicating data between two Dell Unity systems with a configurable recovery point objective (RPO). It allows the source system to continue normal operations without waiting for the destination

  system to acknowledge the completion of the replication.

  References: [Dell EMC Unity: Replication Technologies], [Dell EMC Unity: NAS Capabilities]

• Question 12:

  Which firewall ports are required to be open for a successful outbound connection when configuring integrated secure connect gateway?

  A. 80 and 443

  B. 9443 and 443

  C. 443 and 8443

  D. 80 and 9443

  Correct Answer: C

  The firewall ports that are required to be open for a successful outbound connection when configuring integrated secure connect gateway are 443 and 8443. Integrated secure connect gateway is a feature that enables secure remote access

  to the Dell Unity system through the Unisphere Central web portal. It requires an outbound connection from the Dell Unity system to the Unisphere Central server over the internet. Port 443 is used for HTTPS communication and port 8443 is

  used for WebSocket communication.

  References: [Dell EMC Unity: Unisphere Overview], [Dell EMC Unity: Integrated Secure Connect Gateway]

• Question 13:

  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

  Correct Answer: A

  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 14:

  What is the purpose of a Proxy NAS server?

  A. Access snapshot replicas on the destination side of a replicated file resource.

  B. Increase performance for shared network connections that access NAS servers.

  C. Increase security of production NAS servers.

  D. Access snapshots for testing production NAS servers.

  Correct Answer: A

  The purpose of a Proxy NAS server is to access snapshot replicas on the destination side of a replicated file resource. A Proxy NAS server is a temporary NAS server that is created on the destination system to mount a snapshot replica of a replicated file system. This allows the user to access the data on the snapshot replica for testing, recovery, or other purposes. A Proxy NAS server does not increase performance or security of production NAS servers, nor does it access snapshots for testing production NAS servers.

• Question 15:

  An administrator notices that the communications between Unisphere and the storage system get interrupted.

  Which service task should the administrator perform to fix the issue with minimal impact?

  A. Restart Management Software

  B. Reinitialize

  C. Enable SSH

  D. Reboot Storage Processor

  Correct Answer: A

  The service task that the administrator should perform to fix the issue with minimal impact is Restart Management Software. This service task restarts the management software on both storage processors without affecting the data services or the host I/O. This can resolve the communication issues between Unisphere and the storage system. Reinitialize, Enable SSH, and Reboot Storage Processor are service tasks that have more impact and risk than Restart Management Software. References: [Dell EMC Unity: Unisphere Overview], [Dell EMC Unity: Service Tasks]

• Question 16:

  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

  Correct Answer: C

  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 17:

  A company needs to expand their dynamic pool by 10 TB. The current dynamic pool consists of 63 7.6 TB SSD drives that are configured for RAID 5 (12+1).

  What is the minimum number of drives needed for the pool expansion?

  A. 1

  B. 15

  C. 13

  D. 2

  Correct Answer: C

  To expand a dynamic pool, the number of drives added must be equal to or greater than the stripe width of the pool. The stripe width is the number of data drives plus the number of parity drives in a RAID group. In this case, the stripe width is 12 + 1 =

  13. Therefore, the minimum number of drives needed for the pool expansion is

  13. References: Dell EMC Unity: Dynamic Pools Technical White Paper1, page 8.

• Question 18:

  A system administrator deployed a UnityVSA to their vSphere environment. They did not add the management IP to the UnityVSA during the installation.

  Which command must be used to apply the management IP from the vSphere UnityVSA console?

  A. svc_ipmi

  B. svc_change_hw_config

  C. svc_initial_config

  D. svc_inject

  Correct Answer: C

  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]

• Question 19:

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

  A. 256 MB

  B. 128 MB

  C. 64 MB

  D. 512MB

  Correct Answer: B

  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 20:

  What is the maximum time difference allowed between the current system time (UTC) and the NTP server time during the initial configuration of a Dell Unity system?

  A. 17 min

  B. 7 min

  C. 5 min

  D. 15 min

  Correct Answer: A

  If the time difference between the current system (UTC) time and the NTP server time is too large (approximately 17 minutes), the user cannot configure an NTP server during initial configuration. The user will need to adjust the time while in "Set time manually" mode before changing to "Enable NTP synchronization". This is to avoid potential issues with data replication, snapshots, and audit logs that rely on accurate time stamps. References: Dell EMC Unity: How to change System Time from `Set time manually' option to NTP2, page 1.