Software And Hardware Compatibility And Upgrades; Sfp Module And Fiber-Optic Cable - IBM DS3950 Installation, User's, And Maintenance Manual

IEC 825-11993 CENELEC EN 60 825
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. 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 DS3950 storage subsystem host ports support 2, 4, and 8 Gbps Fibre Channel
speeds. The DS3950 storage subsystem drive ports support only 4 Gbps Fibre
Channel speeds.
Attention: The maximum operating speed of the Fibre Channel port is
determined by two factors: the speed of the SFP module that is installed and 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 7 shows an example of SFP module with fiber-optic cable.
Note: The SFP module and the fiber-optic cable shown are for illustrative purposes
Figure 7. SFP module and fiber-optic cable

Software and hardware compatibility and upgrades

The latest DS3950 controller firmware and NVSRAM, the storage expansion
enclosure drive enclosure ESM firmware, and Fibre Channel and SATA drive CRUs
firmware must be installed to achieve optimal functionality, manageability, and
reliability.
Unless stated otherwise, you can find the latest DS3950 publications, firmware, and
host software at the IBM System Storage Support Web site:
only. The actual SFP module and the fiber-optic cable shape might look
different from the figure shown.
SFP
Module
Fiber-optic
cable
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Chapter 1. Introduction