EMC EMC Certification D-UN-DY-23 Questions & Answers

• Question 1:

  What does the Dell Unity XT system do after a NAS server starts outbound traffic to an external service?

  A. Uses the active production interface

  B. Creates an active interface buffer cache in DRAM

  C. Selects interfaces that are based on advance static routes

  D. Uses Packet Reflect for outbound communication

  Correct Answer: D

  Packet Reflect is a feature that enables the Dell Unity XT system to use the same interface for outbound communication that was used for inbound communication. This feature is useful when the Dell Unity XT system needs to initiate outbound traffic to an external service, such as DNS, NTP, LDAP, or SMTP. By using Packet Reflect, the Dell Unity XT system can avoid routing issues, firewall restrictions, or network address translation problems that may occur when using a different interface for outbound communication. When a NAS server starts outbound traffic to an external service, the Dell Unity XT system uses Packet Reflect to send the packets through the same interface that received the packets from the external service. Therefore, the correct answer is D. Uses Packet Reflect for outbound communication. References: Dell EMC Unity: NAS Capabilities Dell EMC Unity: Unisphere Overview

• Question 2:

  A storage engineer must grant access of a Dell Unity XT provisioned NFS datastore to ESXi-1.dell.local. The NAS server used to create the datastore is configured for NFSv4 protocol with Kerberos NFS owner authentication.

  Which permission level is required for the ESXi host?

  A. Read/write

  B. Read-only

  C. Read/write, enable Root

  Correct Answer: C

  To grant access of a Dell Unity XT provisioned NFS datastore to an ESXi host, the permission level required for the host depends on the NFS protocol and authentication method used by the NAS server. For NFSv4 with Kerberos NFS owner

  authentication, the ESXi host must have the Read/write, enable Root permission level. This allows the ESXi host to read and write data to the datastore, as well as perform administrative tasks such as creating and deleting virtual machines.

  The Read/write permission level alone is not sufficient, as it does not allow the ESXihost to perform root- level operations on the datastore. The Read-only permission level only allows the ESXi host to read data from the datastore, but not

  write or modify it. References: Dell EMC Unity:

  Configuring hosts to access NFS1, page 9.

• Question 3:

  A company has an ESXi host installed with FC HBAs that is connected to a Dell Unity XT storage array. A 500 GB LUN is provisioned to this host from the Unity array and is in production. The VMware administrator has configured a new vSwitch with the NICs on the server intended for iSCSI traffic. The storage administrator is asked to configure software iSCSI and provision a new 1 TB LUN from the storage array using iSCSI.

  What is a consideration when satisfying this request?

  A. Two iSCSI target interfaces must be configured with IP addresses from separate subnets.

  B. Any single host should connect to any single array using one protocol only.

  C. A connection must be established between the host iSCSI initiators and Unity iSCSI targets before provisioning the new LUN.

  Correct Answer: B

  Mixing FC and iSCSI protocols for the same host and array is not supported by Dell EMC Unity. This can cause issues with multipathing, failover, and performance. The best practice is to use one protocol per host and array pair. If the host needs to access both FC and iSCSI LUNs from different arrays, then separate vSwitches and port groups should be used for each protocol. References: Dell EMC Unity: Best Practices Guide1, page 19.

• Question 4:

  A storage administrator must configure replication from a production Dell Unity XT 680F to an offsite DR Dell Unity XT 480. Block resources must be replicated without data loss if the production site becomes unavailable. File resources can

  be replicated with an acceptable amount of data difference on the destination.

  What replication configuration meets the requirements?

  A. Set Unisphere resource filtering to All.

  B. Configure the replication connection mode to Both.

  C. Set an RPO of 0 on the synchronous replication sessions.

  D. Configure the replication interfaces on the 4-port mezzanine card.

  Correct Answer: B

  To meet the requirements, the replication connection mode must be set to Both, which allows both synchronous and asynchronous replication sessions to be configured on the same connection. This way, block resources can use synchronous replication, which ensures zero data loss, and file resources can use asynchronous replication, which allows some data difference on the destination. Setting Unisphere resource filtering to All is not necessary, as it only affects the display of resources in the Unisphere GUI. Setting an RPO of 0 on the synchronous replication sessions is redundant, as synchronous replication always has an RPO of 0. Configuring the replication interfaces on the 4-port mezzanine card is not relevant, as it only affects the performance and availability of the replication network. References: [Dell EMC Unity: Replication Technologies], [Dell EMC Unity: Unisphere Overview]

• Question 5:

  What is a benefit of using vVols?

  A. They enable the automatic import of capability profiles from vSphere to Unisphere.

  B. All VMs on a datastore are snapped simultaneously.

  C. Individual VMs on a datastore can be snapped.

  D. They enable the assignment of isolated file storage partitions.

  Correct Answer: C

  A benefit of using vVols is that individual VMs on a datastore can be snapped. vVols are virtual volumes that are stored on a storage array and managed by vSphere. They enable granular control and management of VM storage. With vVols,

  each VM has its own set of virtual disks that are mapped to corresponding storage objects on the array. This allows the array to perform snapshot operations on individual VMs without affecting other VMs on the same datastore.

  References: [Dell EMC Unity: VMware vSphere Virtual Volumes (vVols) Implementation]

• Question 6:

  An administrator has configured a Host Group to have access to a storage object.

  What are two benefits of this configuration? (Choose two.)

  A. Ensures that snapshots are applied to all LUNs in the group

  B. Provides multiple hosts the same access to NFS Filesvstems

  C. Provides multiple hosts access to the same VMFS Datastores

  D. Ensures that block storage is replicated to the same hosts

  E. Provides multiple hosts access to the same LUNs

  Correct Answer: CE

  A Host Group is a logical grouping of hosts that share the same access permissions to storage objects, such as LUNs, VMFS Datastores, or NFS Filesystems. By configuring a Host Group, an administrator can simplify the management of multiple hosts and ensure consistent access to the storage resources. Some of the benefits of using a Host Group are: Provides multiple hosts access to the same VMFS Datastores: A VMFS Datastore is a block-based storage object that is formatted with the VMware File System (VMFS) and used to store virtual machine files. A VMFS Datastore can be shared by multiple hosts that are part of a VMware cluster. By adding these hosts to a Host Group and assigning the VMFS Datastore to the Host Group, the administrator can ensure that all the hosts have the same access permissions and can access the virtual machines on the Datastore. Provides multiple hosts access to the same LUNs: A LUN is a block-based storage object that is presented to a host as a SCSI device. A LUN can be shared by multiple hosts that have the same operating system and use a cluster-aware file system. By adding these hosts to a Host Group and assigning the LUN to the Host Group, the administrator can ensure that all the hosts have the same access permissions and can access the data on the LUN. References: Dell EMC Unity: Host Configuration Dell EMC Unity: VMware ESXi Hosts and Clusters

• Question 7:

  Which disk format is recommended when deploying Dell UnityVSA OVA?

  A. Thin Provision

  B. Thick Provision Lazy Zeroed

  C. Thick Provision Eager Zeroed

  Correct Answer: C

  When deploying Dell UnityVSA OVA, the recommended disk format is Thick Provision Eager Zeroed, which allocates and zeroes out all the space for the virtual disks at the time of creation. This ensures better performance and avoids

• Question 8:

  What are two prerequisites when creating host configuration for NFS client? (Choose two.)

  A. Tenant information

  B. Network Address

  C. Subnet access

  D. Hostname

  Correct Answer: BD

  Host configuration is the process of defining the host properties and access permissions for a host that connects to the Dell Unity XT system. For NFS clients, the host configuration requires two prerequisites:

  Network Address: The network address is the IP address or the subnet mask of the NFS client that identifies the host on the network. The network address is used to register the host on the Dell Unity XT system and to grant access to the

  NFS filesystems.

  Hostname: The hostname is the name of the NFS client that is resolved by the DNS server or the local hosts file. The hostname is used to display the host information on the Unisphere UI and to enable host monitoring and alerting.

  References:

  Dell EMC Unity: Host Configuration

  Dell EMC Unity: File System Configuration and Management

• Question 9:

  What three VMware datastore types can be defined by using UI or CLI interfaces from the Dell Unity XT platform? (Choose three.)

  A. vVol (Block)

  B. NFS (File!

  C. VMFS (Block)

  D. SMB

  E. RDM

  Correct Answer: ABC

  VMware datastore is a logical container that holds virtual machine files and other data. There are three types of VMware datastore that can be defined by using UI or CLI interfaces from the Dell Unity XT platform: vVol (Block): A vVol datastore is a block-based storage object that is formatted with the VMware Virtual Volumes (vVol) framework and used to store virtual machine files and metadata. A vVol datastore can be created by using the Unisphere UI or the UEMCLI interface on the Dell Unity XT system. A vVol datastore can provide granular control, policy-based management, and improved performance for virtual machines. NFS (File): An NFS datastore is a file-based storage object that is formatted with the Network File System (NFS) protocol and used to store virtual machine files and other data. An NFS datastore can be created by using the Unisphere UI or the UEMCLI interface on the Dell Unity XT system. An NFS datastore can provide scalability, flexibility, and efficiency for virtual machines. VMFS (Block): A VMFS datastore is a block-based storage object that is formatted with the VMware File System (VMFS) and used to store virtual machine files and other data. A VMFS datastore can be created by using the Unisphere UI or the UEMCLI interface on the Dell Unity XT system. A VMFS datastore can provide high performance, reliability, and compatibility for virtual machines. References: Dell EMC Unity: VMware ESXi Hosts and Clusters Dell EMC Unity: Unisphere Overview Dell EMC Unity: Unisphere CLI User Guide

• Question 10:

  Which are two ways to create an asynchronous replication session for a NAS server? (Choose two.)

  A. Use NAS server properties.

  B. Create replication connect.

  C. Use the NAS server wizard.

  D. Create replication interface.

  Correct Answer: AC

  Two ways to create an asynchronous replication session for a NAS server are to use NAS server properties and to use the NAS server wizard. Both methods allow the user to select a source NAS server and a destination NAS server, and

  configure the replication settings, such as the RPO, the replication schedule, and the replication mode. Creating a replication connection or a replication interface are not ways to create an asynchronous replication session for a NAS server,

  but rather prerequisites for enabling replication between two Dell Unity systems.

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