Fabric Scalability; Redundant Fabrics - McDATA StorageWorks 64 - SAN Director Switch Planning Manual

Figure 3-16

Fabric Scalability

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Interswitch Link
Fabric Connection

Redundant Fabrics

Some dual-attached devices support active-active paths, while others
support only active-passive paths. Active-active devices use either
output path equally, and thus use both fabrics and double the device
bandwidth. Active-passive devices use the passive path only when
the active path fails.
When deploying redundant fabrics, it is not required that the fabrics
be symmetrical. As an example, single-attached devices, such as tape
drives and noncritical servers and storage, can be logically grouped
and attached to one of the fabrics.
Businesses are experiencing an unprecedented growth of information
and the requirement to maintain that information online. To meet
these requirements, Fibre Channel SANs provide the theoretical
infrastructure to connect thousands of servers to hundreds of storage
devices. To provide enterprise-class performance, scalable fabric
designs are required. Refer to
Internetworking Solutions
Planning Considerations for Fibre Channel Topologies
Planning Considerations for Fibre Channel Topologies
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Chapter 4, Implementing SAN
for detailed information.
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