Hitachi AMS 2100, Service Manual

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Introduction
1–5
Hitachi AMS 2000 Family Storage System Service Guide
Base unit
The base unit is the primary component of an array. It is used to manage
the storage in the array. Table 1-1 lists the base unit models and their basic
components.
Expansion unit
An expansion unit provides additional storage space and can connect the
base unit to additional expansion units or high-density expansion units. The
same expansion unit is used with all base unit models. The factory
designation for the standard expansion unit is RKAK.
An expansion unit contains two redundant power supplies, two ENC
interface units, and from two to 15 disk drives.
The minimum and maximum number of expansion units and disk drives for
each base unit are shown in Table 1-2 .
:
High-density expansion units
A high-density expansion unit provides additional storage space and can
connect the base unit to additional expansion units or high-density
expansion units. The same high-density expansion unit is used with all three
base unit models. The factory designation for the high-density expansion
unit is RKAKX.
Table 1-1: Base Units
Hitachi Data
Systems Model
Hitachi Factory
Designation
Main Components
AMS 2100 RKS
2 redundant power supplies, 2 controllers,
2 cache backup batteries, and from 4 to 15
disk drives.
AMS 2300 RKM
2 redundant power supplies, 2 controllers,
2 cache backup batteries, and from 4 to 15
disk drives.
AMS 2500 RKHE2
2 redundant power supplies, 2 controllers,
4 cache backup batteries, and 2 fan units.
Does not contain disk drives. Can include 1
or 2 battery expansion units
Table 1-2: Expansion Unit (RKAK) Configurations
Base Unit Expansion Unit
Model Disk Drives Units Disk Drives
Min Max Min Max Min Max
AMS 2100 4 15 0 7 2 per unit 15
AMS 2300 4 15 0 15 2 per unit 15
AMS 2500 0 0 1 32
1st unit: 4
All other units: 2
15