Base Unit; Expansion Unit; High-Density Expansion Units - Hitachi AMS 2000 Series Service Manual

Base unit

The base unit is the primary component of an array. It is used to manage
the storage in the array.
components.
Hitachi Data
Systems Model
AMS 2100
AMS 2300
AMS 2500

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
:
Model
AMS 2100
AMS 2300
AMS 2500

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
Table 1-1: Base Units
Hitachi Factory
Designation
RKS
RKM
RKHE2
Table
Table 1-2: Expansion Unit (RKAK) Configurations
Base Unit
Disk Drives
Min Max
4 15
4 15
0 0
Introduction
Hitachi AMS 2000 Family Storage System Service Guide
lists the base unit models and their basic
Main Components
2 redundant power supplies, 2 controllers,
2 cache backup batteries, and from 4 to 15
disk drives.
2 redundant power supplies, 2 controllers,
2 cache backup batteries, and from 4 to 15
disk drives.
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
1-2.
Expansion Unit
Units
Min Max
0 7 2 per unit
0 15 2 per unit
1st unit: 4
1 32
All other units: 2
Disk Drives
Min Max
15
15
15
1–5