Instruction Manual

virtual disk capacity and redundancy levels. All of this work is done from a c entral loca tion—Command
View EVA. See the Command View EVA online help for more information.
Three levels of virtualization are possible within a SAN—server, fabric, and storage system.
• Ser ver level—useful for small systems—StorageWorks Virtual Replicator implements small scale
virtualization of storage in a Windows NT, Windows 2000, Windows Server 2003 and Novell
NetWare environment.
• Fabric level—SAN-wide virtualization with increased efficiency .
• Storage system level—provides large volumes of pooled storage in virtual d isks and simplifi es
management tasks.
The E nterprise Virtual Array implements storage system level virtualization. Virtu a lization technology, at
the storage system level, creates virtual disks. These virtual disks are created using all the available
physical disk drives, not individual or grouped sets of disks. The host recognizes and uses these virtual
disks like any other disk device.
Storage system level virtualization is a concept in the storage industry that allows you to focus on
higher-level concerns regarding your specificstorageneeds.
With the Enterprise Virtual Array, you no longer nee d to manually present storage pools to the host
servers. That is, you do not choose specific disks and sets of disks to create levels of redundancy. No
decisions need to be made as to which physical disks are involved in each storage unit. When you create
virtual disks, the entire set of d isks in the cabinet is used for load balancing and sparing, which sets aside
extra disk space for failure protection. The Enterprise Virtual Array improves performance bec ause the
data is written across many disks and not directed toward a single or specificsetofdisks.
Setup and management of virtualization is achieved with software and hardware resources. You have
greater freedom and control with the following benefits:
• Faster per formance with improved system response tim e
• All SAN and storage management done from a Web browser
• Simplified load-balanced storage
• Simplified decisions about physical disk setup and partitioning
• Incr eased bandwidth—use of striping algorithms across many disks accessed with multiple
spindles
• Simplified high-availability storage techniques
• Recovery from disk failures includes automatic load balancing
Storage system components
The Enterprise Virtual Array consists of four main components:
• Command View EVA—The management software that communicates with the controllers.
Toget
her, Command View EVA and the controllers control and monitor Enterprise Virtual Array
storage systems.
• VCS—Virtual Controller Software that allows the Enterprise Virtual Array to communicate with
Comma
nd View EVA, via the controllers.
• H a rdware— The physical pieces tha t constitute the Enterprise Virtual Array, such as drives,
enclosures, and controllers. These pieces ar e combined in a rack and are connected to the SAN.
• Host
s servers—The computers that at tach to the storage pools of the Enterprise Virtual Array and
use the virtual d isks like any other disk resource.
These components work together to create an entire storage system solution. Management is
acco
mplished by accessing command View EVA through your browser.
Figure 2 shows the c omplete Enterprise Virtual Array storage solution.
Enterprise Virtual Array 3000/5000 user guide (VCS 3.110)
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