EMC爱存储竞赛
活动官网是http://vip.yingjiesheng.com/2010/emc/
求详细解释
全部是单选题，如下:
1.Which task is performed by a host in an external DAS environment?
Seek time optimization
LUN binding
Disk partitioning
Logical volume creation
*2.Which layer in the Fibre Channel standard defines the class of services?
FC1
FC2
FC0
FC4
*3.A company’s payroll department requires access to the database application Monday through Friday, 9 AM to 5 PM. On Saturday and Sunday the application is down for maintenance. .
Last Thursday at 1 PM the application crashed and six hours were required to fix the problem. What was the availability of the application during last week?
85%
100%
95%
90%
*4.A local replica of the source is created in a storage array for BC purposes. After mounting the target LUN and performing file system check on the secondary server, it is found that the data on the target LUN is inconsistent.
What could be the cause?
The Target is not the same size as the source
The host buffer was not flushed before replication
A file system check was not performed on the source
The source was unmounted during replication
*5.Which type of Fibre Channel port enables connection between two Fibre Channel switches via an Inter-Switch Link (ISL)?
E
FL
NL
F
*6.Which technology uses a single optical fiber to carry signals from different sources on their own, distinct wavelengths?
GigE
DWDM
IP
FC
*7.What is achieved by aligning the infrastructure and management costs with information value?
Compliance
Improved utilization
Simplified management
Lower total cost of ownership
*8.In case of a power failure, which storage array feature protects the contents of the write cache?
Cache flushing
Cache mirroring
Cache vaulting
Cache watermarking
*9.Which statement applies to NAS?
Specialized server for block and content addressed data
General purpose server for block and file level access
Specialized server for the file level data access
General purpose server for block and content addressed data
*10.Other than an iSCSI HBA, which interface cards can be installed in a host to communicate using iSCSI?
NIC, TOE
CNA, IBA
CNA, TOE
NIC, IBA
*11.An application uses a RAID 6 LUN that performs 1600 IOPS with a read/write ratio of 3:1. What is the RAID-corrected IOPS?
3600
7600
2800
5200
*12.Which technology uses the TCP/IP protocol to establish and manage connections between IP-based storage devices and hosts?
FC
FCoE
iSCSI
FCIP
*13.Which best describes the CAS system architecture?
MD5
BLOB
RAID
RAIN
*14.Which host component creates and controls logical volumes?
LVM
File system
Device drivers
Application
*15.Which best describes Recovery Point Objective (RPO)?
The point-in-time to which systems and data must be recovered after an outage
The length of time that the backup software prevents the overwriting of a tape
The maximum allowable time to bring the application back online
The length of time that a particular backup set is retained on tape before it is overwritten by a new backup set
*16.Which best describes incremental backup?
It is a synthetic backup from most recent full backup
It contains only changes since the most recent, cumulative backup
It is a PIT copy of the target volumes
It contains only changes since the most recent backup
*17.Consider an application that requires 1.6 TB of storage capacity and performs 1000 IOPS. You are asked to recommend the number of disks required to meet the application requirement and offer acceptable response time. The disk specifications are as follows:
- Drive capacity = 100 GB
- 15K RPM
- Each disk can perform 100 IOPS
16
15
10
12
*18.What describes the role of NAS?
It increases the number of storage devices directly attached to each server
It provides clear delineation between NFS and CIFS users
It enables users to share file data across different operating environments
It maintains separate networks between clients and storage
*19.In the Windows file system, what information is maintained by the System Access Control Lists?
Object access information that needs to be audited
Troubleshooting information
Rules that are applied during user authentication
Information to control both inbound and outbound traffic
*20.Which statement describes a file system snapshot?
All writes to the source are copied to the snapshot
It contains only data that was copied due to CoFW
It is a point-in-time view of source
It does not require the source to be healthy
*21.An attacker has spoofed the identity of an organization’s remote backup server and requested hosts to send their data. Which security control should be implemented to make the data unusable to the unauthorized user?
Backup snooping
Role Based Access Control
Network bandwidth throttling
Encryption services
*22.Consider the following sequence:
1 – The source receives an I/O write from the host/server.
2 - The I/O is transmitted to the target.
3 – The target sends a receipt acknowledgment to the source.
4 - A write complete status is presented to the host/server.
Which operation is described above?
Asynchronous remote replication
Synchronous remote replication
Pointer-based virtual replication
SAN-based remote replication
*23.A company plans to hosts a video streaming application and you are asked to recommend a RAID level that can be used for this application.
Which RAID level should you recommend?
5
1
3
6
*24.You have defined a backup policy to make full backups every Monday and cumulative backups on the remaining weekdays. In the worst case, how many restores would you have to perform to recover the data if it was deleted accidentally on Friday morning?
4
2
1
3
*25.What is the purpose of an operational backup?
To restore files after they have been corrupted
To save files and records for permanent or long-term preservation
To restore a computer to the operational state following a disaster
To copy and transfer data to an offsite location for disaster recovery
[解决办法]
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