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About Switched Shared Storage and SANs (Storage Area Networks)
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About Fibre Channel Storage Systems and Networks (SANs)
About Switched Shared Storage and SANs (Storage Area Networks)This section explains the features that let multiple servers share
disk-array storage systems on a SAN (storage area network).
A SAN is a collection of storage devices connected to servers via Fibre
Channel switches to provide a central location for disk storage.
Centralizing disk storage among multiple servers has many
advantages, including
•highly available data
•flexible association between servers and storage capacity
•centralized management for fast, effective response to users’ data
storage needs
•easier file backup and recovery
An EMC SAN is based on shared storage; that is, the SAN requires
the Access Logix option to provides flexible access control to storage
system LUNs.
Figure1-9 Components of a SAN
Fibre Channel switches can control data access to storage systems
through the use of switch zoning. With zoning, an administrator can
specify groups (called zones) of Fibre Channel devices (such as
host-bus adapters, specified by worldwide name), and SPs between
which the switch will allow communication.
SP A
Server Server
SP B
Storage systems
Switch fabric
Adapter
Adapter
Adapter
Adapter
Adapter
Adapter
Server
SP A SP B
Switch fabric
Path 1
Path 2