EMC EMC Certifications E20-526 Questions & Answers

• Question 21:

  Which part of the XtremIO architecture do host ports use to access an XtremIO volume?

  A. FA

  B. Initiator

  C. Target

  D. Zone

  Correct Answer: D

  All XtremIO's enterprise features (including Inline Data Reduction, snapshots, XDP, HA, etc.) have been developed as part of the scale-out architecture. All data and metadata are evenly distributed across the entire cluster. I/Os are admitted to the array via all the host ports, utilizing SAN zones and multi-pathing.

  References: Introduction to the EMC XtremIO STORAGE ARRAY (April 2015), page 39

• Question 22:

  A customer currently uses XtremIO native remote replication with four RPAs and a 1 GB WAN link to asynchronously protect all production data. Management has decided that all data stored on the XtremIO must now be protected at the disaster recovery site by synchronous replication.

  How can this be achieved?

  A. Set the Link Policy to Synchronous, Dynamic by throughput

  B. Purchase four additional RPAs.

  C. Set the Link Policy to Synchronous, Dynamic by latency

  D. Use a VPLEX splitter

  Correct Answer: D

  XtremIO with VPLEX provides for both synchronous and asynchronous replication.

  Note: The engine of RecoverPoint is the RecoverPoint Appliance (RPA).

  Incorrect Answers:

  A, B, C: XtremIO with Physical RPA - No Synchronous option available, only asynchronous replication as

  this uses snapshot shipping.

  References: Introduction to the EMC XtremIO STORAGE ARRAY (April 2015), page 55

• Question 23:

  Which values are required to enter a generic workload into the XtremIO Sizing Tool?

  A. Capacity, IOPs, R/W ratio

  B. IOPs, I/O size, bandwidth

  C. IOPs, bandwidth, latency

  D. Bandwidth, I/O size, latency

  Correct Answer: C

  IDC outlines a criteria some criteria for selecting a testing tool:

  *

  Generate workloads

  *

  Capture results for analysis: Throughput IOPS Latency

  References: http://emc.co/collateral/technical-documentation/h15280-euc-xendesktop-vsphere-xtremiosg.pdf, page 87 http://info.xtremio.com/rs/xtremio/images/IDC_Flash_Array_Test_Guide.pdf, page 7

• Question 24:

  A customer has an existing Oracle environment they are considering moving over to XtremIO from VMAX for improved performance. The customer wants to know the expected deduplication and compression savings they can achieve with XtremIO.

  Which tool is appropriate for conducting this assessment?

  A. EMC Backup Tool

  B. EMC Storage Tool

  C. XtremIO Sizing Tool

  D. EMC MiTrend Tool

  Correct Answer: D

  MiTrend has been available for EMC Employees and Partners for years, but it's a valuable tool that Customers can take advantage of also. And the price is awesome. It's FREE !

  Use it for VNX, Clariion, VMAX, and many more.

  References: http://www.pragmaticio.com/2014/11/mitrend-self-service-performance-analysis-for-emc-vnx/

• Question 25:

  

  Refer to the Exhibit.

  A customer has the following XtremIO environment: Read/write ratio is 3:1 I/O size is 8K Write pattern is random Data is compressible

  If an application generates 100,000 IOPS of traffic, how many RPAs are needed to replicate the traffic from one XtremIO array to another XtremIO array over IP?

  A. 1

  B. 2

  C. 3

  D. 4

  Correct Answer: C

  Required bandwidth= 100,000 * 8 * 1024 bytes Provided bandwidth between XtremIO arrays with compression over Fiber Channel: 300 * 1024 * 1024 bytes

  Required number of RPAs: 100,000 * 8 * 1024 / (300 * 1024 * 1024) = 800,000 / (300 * 1024) = 2.6. Three RPAs would be enough.

• Question 26:

  A storage administrator has 20 TB of storage provisioned to their ESXi cluster from a 10 TB XtremIO storage array. The administrator is concerned about running out of physical capacity on the XtremIO.

  Which recommendation will assist the administrator?

  A. Enable VAAI TPSTUN

  B. Increase the compression ratio on the XtremIO

  C. Disable VAAI XCOPY D. Thick provisioned eager zero all VM virtual disks

  Correct Answer: A

  TPSTUN is a VAAI primitive that enables the array to notify vSphere when a LUN is running out of space due to thin provisioning over-commit. The command causes suspending all virtual machines on that LUN. XtremIO supports this VAAI primitive.

  Incorrect Answers:

  C: The XtremIO features for VAAI support include:

  Clone Blocks/Full Copy/XCOPY

  Used for copying or migrating data within the same physical array (VMware term:

  HardwareAcceleratedMove).

  On XtremIO, this allows VM cloning to take place almost instantaneously, without affecting user I/O on

  active VMs.

  D: The XtremIO features for VAAI support include: Zero Blocks/Write Same

  Used for zeroing-out disk regions (VMware term: HardwareAcceleratedInit).

  This feature provides accelerated volume formatting.

  References: https://itzikr.wordpress.com/2015/12/16/host-configuration-for-vmware-vsphere-on-emcxtremio/

• Question 27:

  Who developed the framework for testing All-Flash arrays that is used in the XtremIO PoC?

  A. EMC

  B. Seagate

  C. Micron

  D. IDC

  Correct Answer: D

  IDC outlines a criteria some criteria for selecting a testing tool:

  *

  Generate workloads

  *

  Capture results for analysis: Throughput IOPS Latency

  Etc.

  References: http://info.xtremio.com/rs/xtremio/images/IDC_Flash_Array_Test_Guide.pdf

• Question 28:

  A customer's storage administration team wants to receive e-mail notifications when the XtremIO cluster detects an issue of major seventy. The customer has successfully configured and tested the e-mail server in the XtremIO GUI. However, the e-mail server is not receiving the expected notifications when major severity issues appear.

  What is the cause of this issue?

  A. Alert definitions have not been defined

  B. Event handlers have not been defined

  C. Public reports have not been defined

  D. Private reports have not been defined

  Correct Answer: A

• Question 29:

  What is a characteristic of the XtremIO Snapshot feature?

  A. Snapshots may be deleted in any order

  B. Snapshots can only be deleted in reverse creation order

  C. Only one snapshot may be created or deleted at a time

  D. Snapshots can be restored

  Correct Answer: D

  Any copy in the hierarchy tree can be deleted without effecting the parents or children.

  Incorrect Answers: B: Deleting a snapshot in the middle of the tree triggers an asynchronous process. This process merges the metadata of the deleted entity's children with that of their grandparents. This ensures that the tree structure is not fragmented.

  C: It is possible to create copies of the production volumes in order to protect against logical data corruption. Multiple copies can be created over a short interval in order to provide a fine RecoverPoint Objective (RPO) in a cyclic manner (a superior RPO to a backup).

  References: https://www.emc.com/collateral/white-paper/h13035-wp-introduction-to-xtremiosnapshots.pdf, page 14

• Question 30:

  Which actions are initiated when a snapshot is created on an XtremIO array?

  A. Parent object becomes read only and two auxiliary volumes are created

  B. Parent object remains writeable and one auxiliary volume is created

  C. Parent object remains writeable and two auxiliary volumes are created

  D. Parent object becomes read only and one auxiliary volume is created

  Correct Answer: A

  When a copy is created, the volume's existing metadata becomes an "ancestor" entity (parent object) that is shared between the production volume and the copy. New empty containers are created for subsequent changes to both the production volume and the virtual copy volume. Therefore, the act of creating a copy is instantaneous and involves no data or metadata copies.

  

  References: https://www.emc.com/collateral/white-paper/h13035-wp-introduction-to-xtremiosnapshots.pdf, pages 18