E20-526 Online Practice Questions and Answers

Correct Answer: A

Noting the inefficiencies in VMware's NMP driver, EMC developed a set of drivers specifically designed to overcome these limitations and improve the performance and reliability of the data passing between an array and a server. EMC developed the PowerPath family of products optimized specifically for Linux, Microsoft Windows, and UNIX Operating Systems as well as PowerPath/VE for VMware vSphere and Microsoft Hyper-V hypervisors.

PowerPath is installed on hosts to provide path failover, load balancing and performance optimization VPLEX engines (or directly to the XtremIO array if VPLEX is not used).

Note: VMware, with the cooperation of its storage partners, developed a Native Multipathing Plug-in (NMP). VMware NMP was designed to distribute the load over all the available paths and provide failover protection in the case of path, port or HBA failure, but it has not been fully optimized to work with the controllers in a storage systems. VMware's NMP Round Robin policy does not have the intelligence that PowerPath has as PowerPath uses testing and diagnostics to continually monitor an environment to determine the optimal path for queuing requests and will adapt to current conditions.

References: https://www.emc.com/collateral/analyst-reports/emc-taneja-group-powerpath-tb.pdf

Correct Answer: C

The recommended maximum number of paths to storage ports per host is 16 as per the table below.

References: https://www.emc.com/collateral/white-papers/h14475-wp-xtremio-brocade-best-practices.pdf? isPublic=false , page 12

Correct Answer: A

XtremIO Data Protection (XDP) doesn't require any configuration, nor does it need hot spare drives. Insteadit uses "hot spaces" ?free space in the array.

References: https://www.emc.com/collateral/white-paper/h13036-wp-xtremio-data-protection.pdf , page 23

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

Correct Answer: A

The EMC RecoverPoint family provides cost-effective, local continuous data protection (CDP), continuous remote replication (CRR), and continuous local and remote replication (CLR) that allows for any-point-intime data recovery and a new "snap and replicate" mechanism for local and remote replication (XRP).

Splitter-based replication, using VPLEX RecoverPoint splitter-based replication provides synchronous replication, continuous replication with fine recovery granularity (journal based), and replication for active-active datacenters.

References: Introduction to the EMC XtremIO STORAGE ARRAY (April 2015), page 52

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

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/

Correct Answer: BC

Correct Answer: D

In order to use the XtremIO VSS provider it must be installed on the server where we want to do an application consistent snapshot.

References: http://muegge.com/blog/tag/xtremio/

Correct Answer: B

The block size for both Oracle Cluster Registry (OCR) and Cluster Synchronization Services (CSS) voting files are 512 bytes. I/O operations to these file objects are therefore sized as a multiple of 512 bytes. This is of no consequence since the best practice with XtremIO is to create volumes with 512e formatting.

References: https://www.emc.com/collateral/white-papers/h13497-oracle-best-practices-xtremio-wp.pdf , page 22