General

 

User interface:

ESM boards

Modular components:

 

Built-in power, activity,

Technology and interfaces:

 

High-capacity disk

 

 

and fault indicators

 

— SCSI: Ultra160

 

 

Identification labeling

 

 

 

drives

 

 

— SCSI bus interface: Two

 

Environmental services

 

 

on customer replaceable

 

 

 

 

 

68-pin, Very High

 

 

 

units (CRUs) rear

 

 

 

monitor (ESM) boards

 

 

 

Density Connector

 

 

 

 

indicator lights,

 

 

Power supplies with

 

 

 

Interface (VHDCI)

 

 

 

switches, and connectors

 

 

 

 

 

connectors for SCSI bus

 

 

built-in fans

 

Easy-to-replace drives,

 

 

 

 

 

cables

Technology:

 

 

 

 

power supplies, ESM

 

 

 

Supports disk array

 

 

boards, and fans

 

 

 

 

 

 

 

 

 

 

technology

Disk drive storage

 

 

 

Supports clustering

 

 

 

Current capabilities:

 

 

 

SCSI (Ultra160) host

 

 

 

 

Maximum drives per

 

 

 

 

interface

 

 

 

 

 

 

 

expansion unit: 14

 

 

 

Redundant data storage,

 

 

 

 

 

 

— Drives per SCSI bus: 7

 

 

 

 

power and cooling

 

 

 

 

 

 

 

 

 

 

 

 

system, and ESM boards

 

SCSI buses per unit: 2

 

 

 

Hot-swap technology for

 

— SCSI buses can be

 

 

 

 

drives, power supplies

 

 

configured as one

 

 

 

 

with built-in fans, and

 

 

continuous SCSI bus.

 

 

 

 

ESM boards

 

 

 

 

 

 

 

 

 

 

 

 

 

Clustering support

Clustering is a feature of the expansion unit. Clustering is a means of sharing SCSI buses and disk drives among SCSI controllers to provide redundancy of SCSI controllers and servers. This redundancy is important if a hardware component fails. If a hardware component fails after clustering has been set up, another server will take ownership of the disk drives or SCSI bus.

The IBM Netfinity EXP300 supports twin-tailed clustering. With twin-tailed

clustering, you can connect two IBM ServeRAID® controllers to an EXP300 expansion unit. In the twin-tailed clustering environment, you can use dual-host controllers cabled separately to the EXP300 expansion unit; however, only a single logical bus of 13 drives is supported. Each SCSI device on a SCSI bus must have a unique ID. To prevent conflicts in a twin-tailed configuration, do not install a drive in the bay that uses SCSI ID 6 because your secondary SCSI ServeRAID controller is set to 6.

Service tip: If you use IBM ServeRAID controllers in a cluster configuration, the termination power LED on the back of the expansion unit is useful. The ServeRAID controller provides the signal for termination power. If the termination power LED is not lit, it indicates that a particular EXP300 expansion unit is not attached to a controller that is turned on. Make a note of which EXP300 expansion unit is attached to which server before the hardware is serviced.

Clustering requires additional hardware and specialized software. For more information, visit the IBM Netfinity Cluster Solutions Web site at:

http://www.ibm.com/pc/us/netfinity/clustering

2IBM Netfinity EXP300 - Type 3531 Hardware Maintenance Manual

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IBM 3531 manual Clustering support, General, Disk drive storage