E20-880 Online Practice Questions and Answers

A VNX for File administrator is implementing SnapSure for backup staging. The administrator is concerned that this solution might affect the Production File Systems (PFS). You are asked to describe the possible performance impact of SnapSure checkpoints on the PFS.

How would you respond?

A. COFW will affect PFS write performance.

B. PFS read activity is not affected by Checkpoints.

C. COFW will affect PFS read performance.

D. Checkpoints have no performance impact on the PFS.

A customer is using a virtualized environment with a large number of NFS datastores presented from a VNX system. They are experiencing more than expected network traffic on their datastore networks.

According to EMC best practices, what recommendation should you make to your customer?

A. Adjust NFS.ReadBufferSize and NFS.SendBufferSize to 64.

B. Ensure that all VMware file systems are thin provisioned to improve NFS write I/O.

C. Enable NFS write cache for all NFS datastores.

D. Make sure that the NFS and VMKernel traffic is consolidated onto the same virtual switches.

Your customer recently upgraded their IP switch hardware. Since the upgrade, the customer is experiencing performance degradation on certain NFS exports configured on a VNX for File storage system. The file systems providing the problem exports are all mounted to DataMovers that have been attached to ports on the new switches as part of the upgrade. They have engaged you for advice.

Which action would you recommend?

A. Check for duplex mismatch

B. Change MTU size

C. Change write-aside value

D. Check for speed mismatch

A Snapshot Source LUN performs 500 random 4 KiB IOPs, with a 4:1 R/W ratio. At what rate is chunk data written into the RLP when the session starts?

A. 800 KiB/s

B. 6.25 MiB/s

C. 7.8 MiB/s

D. 12.5 MiB/s

A customer recently added a large number of new users to their VNX for Block storage system. They now complain that the system is slow. You have been asked to fix this problem. Their configuration uses traditional LUNs exclusively. They have a number of Flash drives that are currently unused. Analysis of their application environment shows that several LUNs have skew > 90%.

Which technology would you implement to solve their performance problem?

A. FAST Cache

B. FAST VP

C. Flash RG

D. Pool LUNs

A customer implemented your VNX for File design for a high-performance CAD/CAM application. The design specified several NFS clients, each accessing a single file system in a single-threaded manner. You need to guarantee that each file system resides on an exclusive LUN set.

Which value would you change?

A. default_slice_flag

B. is_greedy

C. is_dynamic

D. stripesize

A customer creates a multi-tiered pool with the following configuration:

Five 200 GB FAST VP optimized Flash drives configured as 4+1 RAID 5 Five 600 GB 15 krpm SAS drives configured as 4+1 RAID 5 Twenty-four 2 TB NL-SAS drives configured as 6+2 RAID 6

The customer's workload consists of 8 kB random I/Os with a R/W ratio of 2:1.

How many host IOPs can the pool support?

A. 3,337 writes/s and 6,673 reads/s

B. 28,060 IOPs

C. 20,560 IOPs

D. 3,697 writes/s and 7,393 reads/s

During a migration from a Windows server to a VNX for file how should virus scanning for the VNX be configured?

A. Disable virus scanning on the VNX

B. Disable virus scanning on the Windows server

C. Disable scan on read on the VNX

D. Disable virus scanning on the VNX and Windows server

Your customer is interested in deploying XtremeSF and XtremeSW together on multiple hosts that will be attached to their new VNX. What would you discuss with your customer?

A. XtremeSF will only accelerate reads while writes will be passed through.

B. XtremeSF will pass though all reads and writes.

C. XtremeSF will only accelerate writes while reads will be passed through.

D. XtremeSF and XtremeSW cannot be used together.

Click the calculator icon in the upper left-hand corner. An application generates 1000 IOPS with a read/ write ratio of 3:1. What is the difference in disk IOPS between RAID 1/0 and RAID 5 for this workload?

A. There are 500 fewer IOPS for RAID 1/0

B. There are 250 fewer IOPS for RAID 5

C. There are 1000 fewer IOPS for RAID 1/0

D. They have the same number of IOPS