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Fibre Channel Storage Components
1-5
About Fibre Channel FC4700 Storage Systems and Storage Networks
With extenders, optical cable can span up to 40 kilometers (25 miles)
or more. This ability to span great distances is a major advantage of
optical cable.
Details on cable lengths and rules appear later in this manual.
Fibre Channel Switches
A Fibre Channel switch, which is required for switched shared
storage (a storage area network, SAN), connects all the nodes cabled
to it using a fabric topology. A switch adds serviceability and
scalability to any installation; it allows on-line insertion and removal
of any device on the fabric and maintains integrity if any connected
device stops participating. A switch also provides
server-to-storage-system access control. A switch provides
point-to-point connections
You can cascade switches (connect one switch port to another switch)
for additional port connections.
To illustrate the point-to-point quality of a switch, this figure shows
just one adapter per server and one switch. Normally, such installations
include two adapters per server and two switches.
Figure1-3 Switch Topology (Port to Port)
EMC1805
Adapter
Server
Adapter
Server
Adapter
Server
Storage system
SP SP
Storage system
SP SP