Switch Models; Benefits; Cascaded Fabric - HP StorageWorks 4000/6000/8000 - Enterprise Virtual Arrays Reference Manual

Switch models

For a small, single-switch SAN fabric, use the SN6000 Fibre Channel Switch; the 8/20q Fibre Channel
Switch (or the HP Simple SAN Connectivity Kit); or an HP SAN, Fabric, or Edge switch (4, 8, 16, or
20 ports). For a larger single-switch SAN fabric, use a SAN, Fabric, or Edge switch (32 to 40 ports),
or a Core or Director switch (64 to 240 ports), which have higher port counts. For a high-availability
SAN, use two switches configured in a dual-fabric SAN.

Benefits

The benefits of a single-switch fabric include:
Easy installation and configuration of servers and storage
Maximum fabric performance because all communicating devices connect to the same switch
Support for local, centralized, and distributed data access needs

Cascaded fabric

A cascaded fabric is a set of interconnected switches, arranged in a tree format, that have one or
more ISLs (Figure
or connect a pair of ISLs between two switches. HP recommends that you have a minimum of two ISL
connections on each switch to provide fabric path redundancy. You should consider using a cascaded
fabric topology if you require multiple groups of devices with localized intraswitch access.
Cascading enables you to:
Achieve optimum I/O activity by connecting servers and storage to the same switch in the cascaded
fabric
Easily scale the fabric over time by adding cascaded switches
2). You can connect one switch to one or more switches using a single ISL to each,
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