IBM EXN1000, Hardware And Service Manual, Page: 44 / 94

Connecting EXN1000 expansion units
This section describes the requirements for connecting the EXN1000 expansion
unit to N series storage systems and other expansion units. For detailed
instructions about how to install and connect one or more EXN1000 expansion
units in a rack, refer to the Installation and Setup Instructions .
v
IBM strongly recommends using optical (fibre channel) cabling whenever
possible.
v Refer to the IBM System Storage N series Introduction and Planning Guide for
details about the maximum number of drive loops, maximum number of
expansion units or hard disk drives per loop, maximum total storage
capacity, and maximum total number of hard disk drives for configurations
using your N series storage system. (For example, you can connect a
maximum of one loop of three fully populated expansion units to an
N3700.)
v
Multipath looping is recommended for all configurations to provide
additional redundancy. This includes single or dual controller and single or
multiple EXN1000 expansion units.
v
Do not mix Fibre Channel EXN2000 or EXN4000 and SATA EXN1000
expansion units in the same loop.
EXN1000 expansion unit cabling requirements
You must meet the cabling requirements discussed in the following sections
when connecting the EXN1000 AT-FCX module to an N series storage system
or to other expansion units.
For the latest information on cabling requirements, see the Installation and
Setup Instructions and the Hardware and Service Guide for your storage system.
Connecting the expansion unit directly to the N series storage system
When connecting the EXN1000 to an N series storage system, you must use
appropriate cables and connectors according to the following guidelines:
v For direct connections to N3700 storage systems with system serial
numbers between 13-00032 and 13-01000 (in general, these are N3700
systems shipped prior to January 31, 2006): Use a NAS-to-EXP fibre
channel copper cable (#2020 or 2022). For attachment to an N3700 Model
A10, one NAS-to-EXP fibre channel copper cable is required. For attachment
to an N3700 Model A20, two NAS-to-EXP fibre channel copper cables are
required.
v
For direct connections to N3700 storage systems with system serial
numbers 13-01001 or higher (in general, these are N3700 systems shipped
after January 31, 2006): Use an LC-to-LC fibre channel optical cable and 2
SFPs for attachment to an N3700 Model A10. Use 2 LC-to-LC fibre channel
optical cables and 4 SFPs for attachment to an N3700 Model A20.
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