EMC EMC Certifications E20-526 Questions & Answers

• Question 41:

  At which point is data compressed when a host sends data to the XtremIO storage system?

  A. Inline before data is written to the SSD

  B. Once data is written to the storage controller

  C. After data is written to the SSDs

  D. After data is in SSD cache

  Correct Answer: A

  XtremIO inline data deduplication and inline data compression services are inline, all the time.

  References: https://www.emc.com/collateral/faq/faq-million-dollar-guarantee-rp-2016.pdf

• Question 42:

  A customer is interested in transitioning their traditional infrastructure to the Cloud by implementing ViPR software-defined storage in an XtremIO environment. Which capabilities will EMC ViPR software-defined storage provide to XtremIO?

  A. Delivers SaaS Centralized management and monitoring Chargeback and billing capabilities

  B. Chargeback reporting capability Centralizes reactive monitoring capability Policy-driven configuration management

  C. Automatically grows storage volumes Slows growth of data Centralized auto-deletes of aging files

  D. Creates virtual storage pools Automates disaster recovery Replaces chargeback capabilities

  Correct Answer: A

  EMC ViPR Controller is a software-defined storage platform that abstracts, pools and automates a data center's underlying physical storage infrastructure. It provides data center administrators with a single control plane for heterogeneous storage systems.

  ViPR enables software-defined data centers by providing features including:

  * Comprehensive and customizable platform reporting capabilities that include capacity metering, chargeback, and performance monitoring through the included ViPR SolutionPack

  References: Introduction to the EMC XtremIO STORAGE ARRAY (April 2015), page 60

• Question 43:

  Based on XtremIO best practice, which byte sector size should be used for volumes hosting Oracle database files?

  A. 256

  B. 512

  C. 1024

  D. 4096

  Correct Answer: D

  Architecting a database on an All Flash Array (AFA) like EMC's XtremIO is best done by reviewing practices to optimize I/O performance. One consideration is the use of Advanced Format and how it impacts the performance of the database Redo logs. Advanced Format refers to a new physical sector size of 4096 bytes (4KB) replacing original 512 byte standard.

  References: https://community.emc.com/community/connect/everything_oracle/blog/2014/07/18/xtremiobest-practices-advanced-format-512e-and-native-modes

• Question 44:

  How many management IP addresses are required on a single XtremIO storage controller?

  A. 1

  B. 2

  C. 3

  D. 4

  Correct Answer: A

  References: https://docs.openstack.org/juno/config-reference/content/XtremIO-cinder-driver.html#xtremiomanagement-ip

• Question 45:

  A customer has a VMware vSphere environment running Native Multipathing (NMP). Which path selection policy should be set for optimal performance when connected to an XtremIO cluster?

  A. Fixed AP

  B. Most Recently Used

  C. Fixed

  D. Round Robin

  Correct Answer: D

  Configuring vSphere Native Multipathing.

  For best performance, it is recommended to do the following:

  Set the native round robin path selection policy on XtremIO volumes presented to the ESX host.

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

• Question 46:

  You have worked with a customer to successfully evaluate their existing server environment using the MiTrend data analysis tool. You have collected the resulting reports and aggregated the data set. You determine the customer's application workload generates a 50:50 read/write ratio with an average of 500K IOPs during peak business hours.

  Which recommended XtremIO model meets the customer's needs?

  A. Starter X-Brick cluster

  B. Single X-Brick cluster

  C. Two X-Brick cluster

  D. Four X-Brick cluster

  Correct Answer: D

  

  References: https://store.emc.com/en-us/Product-Family/EMC-XtremIO-Products/EMC-XtremIO-All-FlashScale-Out-Array/p/EMC-XtremIO-Flash-Scale-Out

• Question 47:

  

  Refer to the exhibit.

  A customer has a VMware Horizon View environment with the following characteristics: One X-Brick XtremIO cluster 100% read during a boot storm 8K read/writes

  What is the maximum recommended number of VDIs the XtremIO cluster can support during a boot storm?

  A. 1625

  B. 1833

  C. 3250

  D. 5094

  Correct Answer: A

  EMC estimates that 150 IOPS per desktop is required in a boot storm. As per table the recommended number of VDIs then is 243,831/ 150, which equals 1625.

  References: https://www.emc.com/collateral/white-papers/h14279-wp-vmware-horizon-xtremio-designconsiderations.pdf, page 32

• Question 48:

  A storage administrator wants to add a volume to their XtremIO storage array using the RESTful API. Which RESTful method should be used to complete this task?

  A. HTTP POST

  B. HTTP PATCH

  C. HTTP LINK D. HTTP PUT

  Correct Answer: A

  An example of a generic wrapper function that queries XtremIO REST API using HTTP/POST to create a new object with specified properties.

  

  References: https://www.emc.com/collateral/white-papers/h14980-wp-accelerate-sql-lifecyclemanagement.pdf

• Question 49:

  Which operation is performed when an XtremIO Snapshot is created?

  A. Pointers to the ancestor metadata are created for the snapshot

  B. Space equal to the size of the ancestor is allocated to the snapshot

  C. A reserved space is created for new snapshot data

  D. A deduplication pass is immediately run against the snapshot

  Correct Answer: A

  When a snap is created, the following steps occur: 1) Two empty containers are created in-memory 2) Snapshot SCSI personality is pointing to the new snapshot sub-node 3) The SCSI personality which the host is using, is linked to the second node in the internal data tree

  References: EMC RECOVERPOINT REPLICATION OF XTREMIO, Understanding the essentials of RecoverPoint Snap-based replication for XtremIO, page 8 https://www.emc.com/collateral/white-papers/ h14296-wp-recoverpoint-replication-of-xtremio.pdf

• Question 50:

  When using XtremIO storage with Solaris (SPARC), what is the EMC recommended I/O size that will deliver sequential I/O more efficiently to XtremIO?

  A. 1 MB

  B. 2 MB

  C. 4 MB

  D. 8 MB

  Correct Answer: C

  EMC recommended setting for Solaris include that the /etc/system file be modified to include the following parameter:

  * Set maximum IO size

  set maxphys = 0x400000

  This also requires increase of the maximum I/O size for the disk driver. The corresponding entry and file for

  this change are different for different Solaris versions, as follows:

  For Solaris 10 (SPARC):

  File: /kernel/drv/ssd.conf

  Setting: ssd_max_xfer_size=0x400000;

  For Solaris 10 (x86):

  File: /kernel/drv/sd.conf

  Setting: sd_max_xfer_size=0x400000;

  Etc.

  References: EMC Host Connectivity Guide for Oracle Solaris, page 167

  https://www.emc.com/collateral/TechnicalDocument/docu5132.pdf