IBM DS3950, Руководство пользователя и инструкция по установке

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Configuring the DS3950
The EXP395 (1814-92H) is the expansion unit specifically designed for the
DS3950 and is the only expansion unit supported behind the DS3950 with the
exception noted below. This is a critical requirement due to the following:
v
Only the EXP395 will provide clients consistent warranty and support
terms and conditions (including geo-specific, SSR installation and support
for the entire system, and code upgrades within the initial warranty
period).
The only exception is that for client investment protection, existing EXP810s
can be migrated from currently installed DS4700s or DS4800s to attach to the
DS3950. A purchase option is required for support of all migration
configurations. With approved migration of EXP810s to a DS3950, special
consideration needs to be made as to proper firmware levels, and careful
coordination of differences in warranty and maintenance terms that will affect
your customer.
Purchase of new EXP810s to attach to the DS3950 will not be supported or
configurable in eConfig.
Note: Disk drive modules that can be ordered in bulk or individually as
customer installable parts for the EXP810 are not supported for use in
the EXP395. Only disk drive modules ordered as feature codes of
1814-92H, and delivered pre-installed in the EXP395, or as
SSR-installable upgrades to EXP395s will be supported.
EXP395 loop redundancy
Note: The term drive loop or drive loop pair used in this publication might be
referred to as a drive channel or drive channel pair when referring to a DS3950
Storage Subsystem in the DS3950 Storage Subsystem Installation, User's and
Maintenance Guide and other DS Storage Subsystem publications. The terms
have identical meanings.
The EXP395 provides redundant loop support when the second ESM is configured,
and when both loops (called A and B) are connected to a DS3950 that supports
redundant loops. If a cable or SFP module fails on drive loop A, drive loop B
provides redundancy, which is an alternate path to your disk drives.
Example of a correct redundant drive loop
Figure 28 on page 44 shows a redundant drive loop that you might create with a
DS3950 storage subsystem and two EXP395s. The numbers provided in Figure 28
on page 44 show the order in which cables should be attached. Note that the
controller port is connected to the port labeled 1B on both the right and left ESMs.
Note: For specific information about cabling a storage expansion enclosure to a
DS3950 storage subsystem, see the
DS3950 Installation, User's, and
Maintenance Guide .
Chapter 3. Cabling the EXP395
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