Handling Fiber-Optic Cables; Installing Sfp Modules - IBM DS4800 User, Installation And Maintenance Manual

Handling fiber-optic cables

Before you use fiber-optic cables, read the following precautions.
Attention:
v Do not route the cable along a folding cable-management arm.
v When attaching to a device on slide rails, leave enough slack in the cable so that
v Route the cable away from places where it can be snagged by other devices in
v Do not overtighten the cable straps or bend the cables to a radius of less than 38
v Do not put excess weight on the cable at the connection point. Be sure that the

Installing SFP modules

The DS4800 host and drive channel ports require SFP modules. SFP modules are
used to convert electrical signals to optical signals that are required for fibre
channel transmission to and from RAID controllers. The DS4800 supports two types
of SFP modules: one with a plastic latch and one with a wire latch. After you install
the SFP modules, you use fiber-optic cables to connect the DS4800 to other fibre
channel devices.
Before you install SFP modules and fiber-optic cables, read the following
information:
v Use only short-wave/multimode SFPs in DS4800 host or drive ports. In DS4800
v The SFP module housing has an integral guide key designed to prevent you from
v Use minimal pressure when you insert the SFP module into a port. Forcing the
v You can insert or remove the SFP module while the port is powered on.
v The operational loop performance is not affected when you install or remove an
v You must insert the SFP module into a port before you connect the fiber-optic
v You must remove the fiber-optic cable from the SFP module before you remove
v The speed of the SFP module determines the maximum operating speed of the
v The only label that identifies whether an SFP module can be operated at 2 Gbps
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IBM System Storage DS4800 Storage Subsystem: Installation, User's, and Maintenance Guide
To avoid damage to the fiber-optic cables, follow these guidelines:
it does not bend to a radius of less than 38 mm (1.5 in.) when extended or
become pinched when retracted.
the rack cabinet.
mm (1.5 in.).
cable is well supported.
configurations, you may use long-wave SFPs only in fibre channel switches that
connect DS4800s over long distances.
inserting the SFP module improperly.
SFP module into a port could cause damage to the SFP module or the port.
SFP module.
cable.
the SFP module from the fibre channel port. See "Removing SFP modules" on
page 50 for more information.
fibre channel port in which the SFP is installed. For example, a 2-Gbps SFP that
is plugged into a 4-Gbps-capable port will limit the speed of that port to a
maximum of 2 Gbps.
only, or at both 2 Gbps and 4 Gbps, is the SFP part number that is printed on the
manufacturing label attached to the SFP. Verify that you use SFPs with the
correct speed requirements in your environment.