HOTSPOT
A company has servers that run Windows Server 2008 R2. You are designing a storage solution for
the servers. The storage solution must meet the following requirements:
• Allow the use of Fibre Channel (FC), Internet SCSI (iSCSI), and Serial Attached SCSI (SAS)
interfaces for connectivity to storage arrays.
• Support storage load balancing.
You need to ensure that the storage solution meets the requirements. Which feature should you
install? To answer, select the appropriate feature in the answer area.
Answer: 
Explanation:
A growing number of organizations require that their data be available at all times. To meet this
requirement, centralized storage must be readily available and immune to outages. Multipathing is
the ability of a system to use more than one read/write path to a storage device. It is a solution that
provides fault tolerance against a single point-of-failure in hardware components.
The Microsoft® Multipath I/O (MPIO) framework helps ensure that your data is available at all times.
MPIO supports multiple data paths to storage, improves the fault tolerance of the storage
connection, and in some cases, provides greater aggregate throughput by using multiple paths at the
same time. This helps improve system and application performance.
Multipathing Support for High Availability
Windows Server® 2008 includes many enhancements for the connectivity of a computer running a
Windows server-class operating system to storage area networking (SAN) devices.
Among the enhancements enabling high availability for connecting Windows-based servers to SANs
is integrated Multipath I/O (MPIO) support. Microsoft MPIO architecture supports iSCSI, Fibre
Channel and serial attached storage (SAS) SAN connectivity by establishing multiple sessions or
connections to the storage array. Multipathing solutions use redundant physical path components —
adapters, cables, and switches — to create logical paths between the server and the storage device.
In the event that one or more of these components
fails, causing the path to fail, multipathing logic uses an alternate path for I/O so that applications
can still access their data. Each network interface card (in the iSCSI case) or HBA should be
connected by using redundant switch infrastructures to provide continued access to storage in the
event of a failure in a storage fabric component.
Failover times vary by storage vendor, and can be configured by using timers in the Microsoft iSCSI
SoftwareInitiator driver, or modifying the Fibre Channel host bus adapter driver parameter settings.
New MPIO features in Windows Server 2008 include a Device Specific Module (DSM) designed to
work with storage arrays that support the asymmetric logical unit access (ALUA) controller model (as
defined in SPC-3), as well as storage arrays that follow the Active/Active controller model.