IBM Midrange System DS4000 Series Hardware Manual page 95

Figure 3-54 shows a closer view of a DS5020 controller.
Figure 3-54 DS5020 controller photo rear view
SPF modules
The storage subsystem supports a fiber-optic interface for host and storage expansion
enclosure connections. You must install a Small Form-factor Pluggable (SFP) module in each
interface connector on the controller where a fiber-optic cable is to be installed.
Note: Do not install an SFP in any port that will not have a fiber-optic cable attached.
Remove any SFP from any port that does not have fiber-optic cables attached.
The DS5020 storage subsystem host ports support 2, 4, and 8 Gbps Fibre Channel speeds.
The DS5020 storage subsystem drive ports support only 4 Gbps Fibre Channel speeds.
The maximum operating speed of the Fibre Channel port is determined by two factors:
The speed of the SFP module that is installed
The speed of the Fibre Channel connection
For example, a 4 Gbps SFP that is plugged into a 8 Gbps-capable port will limit the speed of
that port to a maximum of 4 Gbps. Conversely, an 8 Gbps SFP that is plugged into a
4 Gbps-capable port will limit the speed of the port to a maximum of 4 Gbps. Carefully check
the SFP IBM part number, option number, and FRU part number to identify its speed. There
are no physical features that distinguish an 8 Gbps SFP from a 4 Gbps SFP.
Figure 3-55 shows an example of SFP module with fiber-optic cable.
Fiber-optic
cable
Figure 3-55 DS5020 SFP Module
SFP for all FC ports are shipped with the system.
Protective
SFP
module
Chapter 3. IBM System Storage DS4000 and DS5000 hardware
Wire
tab
cap
90°
SFP
module
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