E20-526 XtremIO Solutions and Design Specialist Exam for Technology Architects Question and Answers

Disk service time T(s) = 32 ms (service time for one I/O).

Response time T(r) is calculated as: T(s) / (1 – Utilization), which here calculates to 32 ms/ (1-0.75) = 128 ms.

References:https://community.emc.com/thread/145100?tstart=0

With VMware ESX 5.5, the VMware hypervisor cannot work with LUNs that use a logical block size of 4K. When using VMware, be sure to specify Normal (512 LBs) from your XtremIO array.

References:https://gruffdba.wordpress.com/2015/08/02/4k-logical-block-size-size-fails-on-vmware/

EMC XtremIO(All-Flash) : SAN, inline deduplication, 8K fixed chunk size;

References:https://www.linkedin.com/pulse/deduplication-fake-reality-mike-uzan

XtremIO clusters with 60 TB of physical usable flash capacity can now logically support 360 TB or more of capacity at typical 6:1 data reduction (deduplication plus compression) ratios. Here we have a 4:1 reduction ratio, so 25 TB would be enough. The 250,000 IOP requirments indicates that we need at least two Bricks.

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

The first step is to re-install the XMS image, in the event it is a physical XMS then you may install an image via a USB flash drive or for a virtual XMS simply deploy the provided VMware OVA image.

The following step is to upload the XMS software to the images directory of the XMS and login with install mode ……..

Once logged into the XMS console with xinstall then perform the following sequence of steps:

1. Configuration

5. Perform XMS installation only

11. Run XMS Recovery

Options to choose when running the “XMS Recovery”:

References:https://davidring.ie/2015/02/20/emc-xtremio-redeploying-xms-xtremio-management-server/

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.

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