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XX-309E1-C6

August 1991

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Document:	VAXft Systems Configuration Guide
Order Number:	XX-309E1-C6
Revision:
Pages:	62
Original Filename:	https://manx-docs.org/collections/mds-199909/cd1/vax/vxftbpg2.pdf

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VAXft Systems
Configuration Guide
Order Number: EK–VXFTB–PG–002

August 1991
This document describes how to configure the VAXft Systems hardware.

Revision/Update Information:

This manual supersedes the VAXft 3000
Guide to Fault Tolerant Systems, EKVXFTA-PG-001.

Operating System and Version: VMS Version 5.4
Software Version:

VAXft System Services Version 1.2

VMS Volume Shadowing:

Phase II

Hardware Version:

VAXft Systems

Digital Equipment Corporation
Maynard, Massachusetts

First Printing, May 1990
Revised, August 1991
The information in this document is subject to change without notice and should not be
construed as a commitment by Digital Equipment Corporation.
Digital Equipment Corporation assumes no responsibility for any errors that may appear in this
document.
Any software described in this document is furnished under a license and may be used or copied
only in accordance with the terms of such license. No responsibility is assumed for the use or
reliability of software or equipment that is not supplied by Digital Equipment Corporation or its
affiliated companies.
Restricted Rights: Use, duplication, or disclosure by the U.S. Government is subject to
restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in Technical Data and Computer
Software clause at DFARS 252.227–7013.
© Digital Equipment Corporation 1991.
All rights reserved. Printed in U.S.A.
The Reader’s Comments form at the end of the hardcopy version of this document requests the
user’s critical evaluation in preparing future documentation.
The following are trademarks of Digital Equipment Corporation: DEC, DECnet, DELNI,
DECserver, DECsystem, DSSI, MicroVAX, ThinWire, TK, VAX DOCUMENT, VAX-11/780,
VAXcluster, VAXft, VAXsimPLUS, VMS, VT, and the DIGITAL logo.
IBM is a trademark of International Business Machines Corporation.
This document is available in printed and online versons.

This document was prepared using VAX DOCUMENT, Version 1.2

Navigational Map for the VAXft Systems Documentation

Overview
Information
(VAXft Systems)

Hardware
Information
(VAXft Systems)

Operating System
(VMS)

Software
Information
(VAXft System Services)

Customer Letter

Site Prep and
Installation Guide

VMS Upgrade and
Installation Manual

Using Factory−Installed Software
with VAXft Systems

Owner’s Manual

VMS Upgrade and
Installation Supplement:
VAXft 3000

Installation
Guide

Software Product
Description

VAXft Systems
Configuration Guide

Mini−Reference
Guide

Release Notes

VAX Wide Area Network
Device Drivers

Manager’s
Guide

Release Notes
VMS Volume
Shadowing Manual
Reference
Manual

= Book

= Online

Online Help

= Tape
Error Message
Manual
= Bookreader

Master Index
MR−5492−RA

iii

Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

vii

1 Introduction
1.1
Digital’s Family of Fault Tolerance Systems . . . . . . . . . . . . . . . .
1.2
System Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.1
System Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.1.1
Processor Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.1.2
Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.1.3
Crosslink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.2
System Console . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.3
Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3
System Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3.1
VMS Operating System . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3.2
VMS Volume Shadowing . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3.2.1
Guidelines for Shadowing Data . . . . . . . . . . . . . . . . . . . .
1.3.3
VAXft System Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4
System Management Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5
Power Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.6
Cooling Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.7
Summary of System Characteristics . . . . . . . . . . . . . . . . . . . . . .

1–1
1–2
1–5
1–6
1–7
1–7
1–7
1–8
1–9
1–9
1–9
1–10
1–11
1–11
1–11
1–13
1–13

2 VAXft Systems Configurations and Options
2.1
2.2
2.2.1
2.3
2.3.1
2.4

Common Features and Options for Configuring VAXft Systems
...................................................
The VAXft Model 110 System . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 110 Mass Storage and Module Options . . . . . . .
VAXft Model 310/410 Entry System . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 310/410 Entry System Mass Storage and
Module Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 310/410 Expanded System . . . . . . . . . . . . . . . . . . . .

2–1
2–6
2–7
2–8
2–9
2–10

iii

2.4.1
2.5
2.5.1
2.6
2.6.1
2.7
2.7.1
2.8
2.8.1
2.9
2.10

VAXft Model 310/410 Expanded System Mass Storage and
Module Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 610 Entry System . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 610 Entry System Mass Storage and Module
Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 610 Expanded Systems . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 610 Expanded Systems Mass Storage and
Module Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 612 Entry VAXcluster System . . . . . . . . . . . . . . . . .
VAXft Model 612 Entry VAXcluster Mass Storage and
Module Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 612 Expanded VAXcluster System . . . . . . . . . . . . . .
VAXft Model 612 Expanded VAXcluster System Mass Storage
and Module Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Upgrading A VAXft Model 610 System to a VAXft Model 612
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Summary of System Configuration Characteristics . . . . . . . . . . .

2–12
2–13
2–14
2–16
2–19
2–21
2–23
2–24
2–26
2–27
2–28

3 Networking Communications
3.1
3.2
3.3
3.4

Ethernet Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DECserver Terminal Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Synchronous Communications . . . . . . . . . . . . . . . . . . . . . . . . . . .
Summary of System Communication Characteristics . . . . . . . . . .

3–1
3–3
3–4
3–5

4 System Service and Warranty
4.1
4.2
4.2.1
4.2.2
4.3
4.4

Glossary

Service and Repair Features . . . . . . . . . . . . . . . . . . . . . . . . . . . .
System Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Standard Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Digital Assisted Services Program . . . . . . . . . . . . . . . . . . . . . . . .
Summary of System Service and Repair Features . . . . . . . . . . . .

4–1
4–2
4–2
4–2
4–2
4–3

Figures
1–1
1–1
1–2
1–4
2–1
2–2
2–3
2–4
2–5
2–6
2–7
2–8
2–9
2–10
2–11
3–1
3–2
3–3

VAXft System Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seven-Slot Backplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Five-Slot Backplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Most Common Causes of System Failure Due to
Environmental Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seven-Slot Backplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Five-Slot Backplane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disk Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 110 Configuration . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 310/410 Entry System Configuration . . . . . . . .
Model 310/410 Expanded System Configuration . . . . . . . . . .
Model 610 Entry System Configuration . . . . . . . . . . . . . . . . .
Model 610 Expanded System Configuration with One
Expansion Cabinet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Model 610 Expanded System Configuration with Two
Expansion Cabinets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAXft Model 612 Entry VAXcluster Configuration . . . . . . . . .
VAXft Model 612 Expanded VAXcluster Configuration . . . . . .
System Configured to Single Ethernet . . . . . . . . . . . . . . . . . .
System Configured to Dual Ethernet . . . . . . . . . . . . . . . . . . .
Synchronous Communication Lines Using Y-Connectors . . . .

1–4
1–5
1–6
1–12
2–2
2–3
2–6
2–7
2–9
2–11
2–14
2–17
2–18
2–22
2–25
3–2
3–3
3–5

Tables
2–1
2–2
2–3
2–4
2–5
2–6
2–7
2–8

Common Options for the VAXft Systems . . . . . . . . . . . . . . . .
Module Options for the Model 110 . . . . . . . . . . . . . . . . . . . . .
Module Options for the Model 310/410 Entry System . . . . . .
Options Table for Model 310/410 Expanded System . . . . . . .
Module Options for the Model 610 Entry System . . . . . . . . . .
Options Table for Model 610 Expanded Systems . . . . . . . . . .
Module Options for the Model 612 Entry VAXcluster System
................................................
Options Table for Model 612 Expanded VAXcluster System
................................................

2–3
2–8
2–10
2–13
2–15
2–20
2–23
2–27

Preface
Purpose of This Guide
This manual is a guide to configuring the members of the VAXft Systems
family of fault tolerant systems.

Intended Audience
This guide is intended for use by Digital customers or potential customers who
are interested in VAXft fault-tolerant systems configurations.

Related Documentation
The following documents contain further information on the VAXft Systems
and VAXft System Services, the software used with the VAXft systems.
VAXft systems:
•

VAXft Systems Site Preparation and Installation Guide

•

VAXft Systems Mini-Reference Guide

•

VAXft Systems Technical Description

•

VAXft Systems Owner’s Manual

VAXft System Services:
•

VAXft System Services Release Notes

•

VAXft System Services Manager’s Guide

•

VAXft System Services Installation Guide

•

VAXft System Services Reference Manual

•

VAXft VMS: System Services Error Message Manual

•

VMS Upgrade and Installation Supplement: VAXft 30001

Available with VMS software kit.

vii

•

VMS Volume Shadowing1

Conventions
This document uses the following conventions:

viii

Convention

Meaning

italics

An italicized term indicates that it is a new term described either
in the text or in the glossary. Italics may also identify the title of
a document.

1
Introduction
1.1 Digital’s Family of Fault Tolerance Systems
In designing the VAXft fault-tolerant systems, Digital used its own hardwareintensive architecture. This architecture features fully redundant hardware
and self-checking checkers for each set of hardware components. Digital also
supports its fault-tolerant systems with an industry-leading service offering.
These features of the VAXft systems provide the following innovations for
fault-tolerant computing:
•

Fully redundant hardware
One copy of each type of element in the system is always available.

•

No single point of hardware failure
No single hardware element is capable of bringing down the entire system.

•

No single point of repair
All repairs can be made without bringing down the entire system.

•

Uninterruptible Power Supply (UPS)
Power outages of short duration, brownouts, and power fluctuations, which
are the most common environmental causes of computer failures, are
eliminated.

•

Self-checking checkers
These checkers ensure that system integrity is not compromised if a fault
occurs in the checking logic.

By combining these innovations with the highly successful VAX architecture,
Digital has extended the range of its VAX family of computers into state-ofthe-art fault-tolerant systems. The VAXft system family is designed to meet
fault-tolerant requirements.

Introduction 1–1

Digital’s strategy is to provide you with a fault-tolerant VAX computer system
that requires no change in your application code and is fully compatible with
existing VAX systems.
The VAXft systems use the VMS operating system and a layered product,
VAXft System Services, to support its hardware architecture. The VAXft
systems will run any application or layered product designed to run on
the VMS operating system. In this way, Digital continues to protect your
investment in applications development.
Because the VAXft systems are based on the popular VAX architecture, you can
mix conventional and fault-tolerant systems in your configurations. Therefore,
you only have to put a fault-tolerant system where it is needed and can use
conventional or high availability systems elsewhere. All the VAX systems
present a common programming and operator interface.
Digital’s cost-effective overall approach lets you put fault tolerance only where
you need it in your system design. No other computer vendor lets you do that.
For example, the VAXft systems can be used as a:
•

Standalone system

•

Front end system in a distributed application

•

Back end system in a distributed application

Digital’s VAX architecture is the most expandable in the industry. Digital
offers you conventional, high-availability, and fault-tolerant systems, all within
the same architecture. The VAXft systems provides a seamless upgrade for
your critical applications in a networked environment that results in a high
degree of system reliability and availability.

1.2 System Architecture
Each VAXft system consists of two identical sets of components configured in
dual zones. Each zone is a complete computer system, fully capable of servicing
the application by itself. Figure 1–1 illustrates the logical system design.
This dual zone design ensures there is no single point of hardware failure,
and that a single fault or hardware failure in one zone does not cause system
failure. Separate power supplies for each zone (including separate power cords)
minimize system failure due to loss of external power in a single zone.
Each zone in a VAXft system contains identical CPU and memory modules.
Both CPUs and memory in each zone execute the same instruction at the same
time. This type of operation is called lockstep. Because the zones are peers
and operate in this synchronous fashion, no delay is caused by a transfer of
operations from the failed CPU to the remaining CPU. Indeed, there is no
1–2 Introduction

transfer at all. With each zone running in lockstep, the remaining zone simply
continues to operate while the failed zone is halted waiting for repair.
To maximize the benefits of redundancy for fault tolerance, the VAXft system
interconnects are also duplicated to eliminate any connectivity losses due to
cable failure. Crosslink cables link both system zones and provide parallel data
paths between the zones. Figure 1–1 shows some of these redundant features
of the VAXft systems.

Introduction 1–3

Figure 1–1 VAXft System Diagram
Modem

Modem

SCHOLAR

Remote

VT320

Tape
Drive

Local Console Terminals

Disk
or
Tape

Disk

VT320

Remote

Disk

1 2 3 4 5 6 7

E C M C
T P E O
H U MM
E
OM
R
R
N
Y
E
T

Crosslink Cables
Ethernet

Synch
Lines

Synch
Lines
MR-5523-AD

Main memory for the VAXft systems is configured redundantly up to 128
megabytes in increments of 32 megabytes. Refer to Section 1.2.1.2, Memory,
for more details.
The VAXft systems supports up to two terminals per zone, one local terminal
and one remote terminal. See Section 1.2.2, System Console, for more details.
System power resources include power components and separate power cords
to external power sources for each zone; and each zone has its own UPS for
auxiliary power. Refer to Section 1.5, Power Subsystem, for more details.

1–4 Introduction

1.2.1 System Hardware
There are seven module slots in each zone (five in the Model 110) for four
types of hardware modules. The CPU, system I/O controller modules, memory
modules, and communications controller modules designed for the VAXft
systems reside in the module slots and connect directly to the backplane
in each zone. Redundant backplanes eliminate the possibility of a single
point of failure at this level. The modules are specifically designed for simple
maintenance and can be inserted or removed from the front of the system
cabinet. Figure 2–1 and Figure 2–2 show the arrangement of the system
modules.
Figure 1–1 Seven-Slot Backplane

1 2 3 4 5 6 7

E C M
N P E
E U M
T
O
/
R
D
Y
S
S
I

1 2 3 4 5 6 7

E C M
N P E
E U M
T
O
/
R
D
Y
S
S
I

Crosslink Cables
MR-5525-AD

Introduction 1–5

Figure 1–2 Five-Slot Backplane

1 2 3 4 5

E C M
N P E
E U M
T
O
/
R
D
Y
S
S
I

Crosslink Cables
MR-5526-AD

The minimum configuration of required logic modules in each zone of the
VAXft systems includes: one CPU, one memory module, and one system I/O
controller.
Synchronous communication modules are not required, although some
applications may require such modules. For a more detailed discussion of
module configuration options for the VAXft systems, refer to Chapter 2.
1.2.1.1 Processor Modules
A VAXft system has two processor modules, one in each zone, which run in
lockstep. If one processor module fails during operation, the other processor
module continues to provide service to the application.
Each processor module provides the following VUPs of processing power.
•

Model 110 System — 2.4 VUPs

•

Model 310 System — 3.8 VUPs

•

Models 410 and 610 System — 6.0 VUPs

•

Model 612 VAXcluster System — 12.0 VUPs

One VUP is equal to the processing power of the VAX-11/780 processor. Each processor
module also includes a 1-kilobyte internal cache memory, supplemented by an external
32-kilobyte cache memory, and a system logic clock for synchronization of the zones.

1–6 Introduction

1.2.1.2 Memory
Each memory module for the VAXft systems contains 32 megabytes of fully
checked memory on a single board. Each memory module features single-bit
correction, double-bit detection, address and function verification, and parity
checking. Up to four (three for the Model 110 system) 32-megabyte memory
modules can be configured in each zone. The minimum system configuration
has one memory array in each zone.
For lockstep operation, the system must be configured with equal amounts of
memory in each zone.
1.2.1.3 Crosslink
Crosslink cables provide the communications paths between the CPU modules
in each zone.
Between the zones, the crosslink provides two types of paths: serial and
parallel. The serial path is used to establish initial communications between
the zones. The parallel path operates only after the clocks in each zone have
been synchronized.

1.2.2 System Console
The VAXft system console is a combination of hardware and software that
enables the system to boot itself and lets you perform routine system
maintenance.
The console functions enable you to:
•

Issue console commands

•

Boot the system either automatically or interactively

•

Install the VMS operating system

•

Examine control and status registers and run diagnostic tests

•

View messages from the console program, diagnostics, and the VMS system

•

Provide remote dialin/dialout capability

•

Provide input to the operating system for the system manager or operator

System I/O controller modules containing DSSI/Ethernet/Console adapters
interface the system with the DSSI, Ethernet and console. To support console
operations, these modules are configured redundantly, one in each zone, to
enable four console ports. The ports support one local terminal and provide
access to one remote terminal in each zone by modem, as shown in Figure 1–1.

Introduction 1–7

All four physical console lines operate as a single logical system console.
Output appears on all four console terminals, and input can be entered from
any console terminal.
Local terminals can be a combination of video display terminals, hardcopy
terminals, or video display terminals with printer. A minimum of two
terminals are required with the system.
During normal operation, only one terminal is required for system operations.
Two terminals are normally active during system repair. One terminal can be
used to manage the system, while the other is used to manage system repair.
Remote console ports can be used for system access from remote locations.

1.2.3 Communications
Synchronous
Synchronous communication for the VAXft systems is provided by the DEC
Wide Area Network Controller 620 (DEC WANcontroller 620), which is a twoline synchronous fault-tolerant communications controller option designed
specifically for the VAXft systems.
The DEC WANcontroller 620 supports Digital-standard layered communications software for the DECnet-VAX, VAX Packetnet System Interface (PSI),
VAX 2780/3780 BISYNC Protocol Emulator, and DECnet/SNA products.
The two lines are independently managed and operated so different protocols
can run simultaneously. The DEC WANcontroller 620 is capable of line speeds
up to 64 kilobits per second.
The maximum that can be configured is eight DEC WANcontroller 620 modules, four per zone, providing 16 synchronous non-redundant communication
lines. Configuring the modules redundantly, two in each zone, enables a
maximum of only eight lines.
Asynchronous
Support for asynchronous communications devices, such as user terminals,
is provided through the use of Ethernet terminal servers. An Ethernet port
can be connected to a thick wire or ThinWire Ethernet. See the Networks and
Communications Buyer’s Guide, for more information.

1–8 Introduction

1.3 System Software
Many of the VAXft systems’ fault-tolerant features are implemented in
software. Therefore, the VMS operating system software and layered products
are integral components of the fault-tolerant operation of the VAXft systems.
All VAXft systems require the following software for fault-tolerant operation:
•

VMS operating system software

•

VAXft System Services software, which supports the system’s fault-tolerant
hardware features

•

VMS Volume Shadowing, which allows for redundancy of disk drive data

In addition to the software components that are part of the fault-tolerant
operation, you can:
•

Use existing VMS applications software and layered products, which run
unchanged and do not need to be recompiled

•

Integrate or migrate applications from other VAX systems to the VAXft
systems without change

•

Develop applications on conventional VAX systems or the VAXft systems

All systems include the licenses for the required software.

1.3.1 VMS Operating System
The multitude of VMS layered products and VMS applications can be run
on the VAXft systems without modification or recompiling. In addition, in
situations where operators are already trained in VMS operations, little
additional training is needed for the VAXft systems.

1.3.2 VMS Volume Shadowing
VMS Volume Shadowing is a significant component of the VAXft systems’
fault-tolerant capability. It enables all disks, including the system disk, to be
shadowed within a single system or across many systems on the Ethernet.
VMS Volume Shadowing replicates data at the volume level and ensures that
the loss of a disk drive does not affect the ability of an application to run.
You can shadow as many drives as required by your application. Up to three
members are allowed in each shadow set.
For maximum system availability, shadow set members should be accessible
from different zones on different DSSI buses. For more detailed information on
system configurations, refer to Section 1.3.2.1.

Introduction 1–9

1.3.2.1 Guidelines for Shadowing Data
Volume shadowing is not required for all disks on the VAXft systems. However,
volume shadowing enables the system to provide access to important data
whenever it is needed, so disks containing critical data should be shadowed.
The best approach to shadowing disks is to identify critical needs and to protect
data accessibility and availability in those areas by maintaining shadow sets of
important data.
There is no restriction on the number shadow sets allowable. The maximum
number of members for a shadow set is three. Members of a shadow set should
reside on different DSSI buses and in separate cabinets to optimize data
accessibility and availability within the VAXft system.
To determine which disks require shadowing, answer the following questions.
•

Is availability of the data on the disk critical?
For example, does the data on the disk need to be available at all times?
If so, this disk should be included in the shadowing operation. If the
system must be up all the time, the system disk is critical and needs to
be shadowed. But, for example, data needed for an annual report may not
require shadowing if there is a consistent procedure for backing up system
data.

•

Is the data written to the disk critical?
Sometimes shadowing of a disk is necessary because because the data is so
critical that it cannot be lost. For example, a disk that records transactions
at an automatic teller machine should be shadowed because the data must
be available immediately to adjust balances, and a copy must be retained
for reference at all times. In this case, a simple backup procedure would be
insufficient because data could be lost if the drive where it is recorded fails.
Shadowing of this disk would ensure that the data is available at all times
for immediate access or reference at a later date.

•

Must a disk be shadowed to adhere to legal or auditing requirements?
Some businesses must adhere to corporate and government requirements
to protect data. Shadowing can be used to fulfill these requirements.

1–10 Introduction

1.3.3 VAXft System Services
VAXft System Services runs in conjunction with the VMS operating system to
support the fault-tolerant features of the VAXft systems.
Features of the VAXft System Services software include support for the
following capabilities:
•

Automatic failover of hardware

•

Hardware fault isolation and recovery

•

Automatic dialout notification of faults

•

Configuration management of I/O components

The VAXft System Services software also provides DCL-level commands to
start, stop, and show zones.

1.4 System Management Utilities
Additional software for the VAXft systems provides tools and utilities you use
to manage the system.
The FTSS$CONTROL Utility allows you to define the dialout telephone
numbers used by the autonotification feature. See Section 4.1, Service and
Repair Features, for more details on this utility.
The Failover Set Manager Utility enables you to manage members of the
failover sets of Ethernet adapters. The Failover Set Manager allows the
addition or removal of failover set members and displays member status. Refer
to the VAXft System Services Reference Manual and VAXft System Services
Manager’s Guide for more details.

1.5 Power Subsystem
The VAXft systems feature a universal AC power system that supports 120
VAC requirements for the U.S. and 240 VAC requirements for the international
market. The power system provides the voltages required to operate all
internal components of the system, including the computer logic, memory,
disks, tape, and cooling fans. The system features separate power cables for
each cabinet, to enable connection to external power sources.
External power can be 120 VAC or 240 VAC, or 48 to 60 VDC on all models
except the Model 110 system. See the VAXft Systems Site Preparation and
Installation Guide, for more details.

Introduction 1–11

Loss of external power is the leading cause for environmentally induced system
failure. See Figure 1–4 for an illustration of typical outage causes leading to
system failure. The VAXft systems are able to counteract this by switching
to the Uninterruptible Power Supply (UPS). The UPS allows for a controlled
shutdown of the system to eliminate loss of data. The integral UPS in each
zone permits the system to tolerate brownouts, or brief or full outages due to
loss of external power source, by supplying power to all internal components
for up to 15 minutes in each 24-hour period. The VAXft Model 110 system does
not support an integral UPS; an external UPS must be ordered if you require
uninterruptible power.
If external power returns within 15 minutes, the system automatically switches
back to the external power source.
For critical applications that tolerate no downtime, an external generator
should be included in the installation for times when power is lost for longer
than 15 minutes.
External devices such as console terminals, user terminals, modems, and
terminal servers are not supported by the VAXft systems in the event of a
power outage. An external UPS used to support these devices is available from
Digital.
Figure 1–4 Most Common Causes of System Failure Due to Environmental
Conditions

Flood

Quake

Loss of External
Power Source

Fire
Lightning
Other

MR−3994−RA

1–12 Introduction

1.6 Cooling Monitor
The VAXft systems are designed to operate in a normal temperature-controlled
office space. Temperature thresholds are 10°C and 40°C, or about 50°F and
104°F. If the environment exceeds the system’s thresholds, a shutdown occurs
automatically.
The system has internal cooling monitors in each zone to ensure that
thresholds on the high end are not exceeded. Fan speed is increased when
room temperature rises above an acceptable threshold. The monitor reports
harmful temperature fluctuations to the system, and the autonotification
dialout procedure is initiated to notify the user or Digital Customer Services.

1.7 Summary of System Characteristics
Important characteristics of the VAXft systems include:
•

Hardware-intensive, fault-tolerant VAX architecture, featuring redundant
subsystem hardware and self-checking checkers within each zone

•

Full VAX compatibility with the VAXft systems running the industry
standard VMS operating system, and fully supporting all layered
products and applications designed for VAX computers without change
or recompilation

•

Up to 12.0 times the processing power of the VAX-11/780

•

Fault detection and isolation of all hardware faults

•

Multiple Ethernet Local Area Networks

•

DEC WANcontroller 620 support for multiple protocols and synchronous
communications lines

•

High performance Digital Storage Systems Interconnect buses for mass
storage for the VAXft systems

•

Online system repair while the system continues to service your application

•

Separate cabinets for each zone that provide improved protection from
human error and easy maintenance and repair of the system from the front
of the cabinets

•

Battery-backup to tolerate external power fluctuations

•

Cooling monitors to maintain acceptable temperature

•

Automatic dialout to notify you or Digital Customer Services of system
failure.

Introduction 1–13

2
VAXft Systems Configurations and
Options
Digital Equipment Corporation offers a family of VAXft systems to satisfy your
fault-tolerant computing requirements. The systems vary in processing power
and amount of mass storage. Supported configurations are:
•

VAXft Model 110 System

•

VAXft Model 310 or 410 Entry System

•

VAXft Model 310 or 410 Expanded System

•

VAXft Model 610 Entry System

•

VAXft Model 610 Expanded Systems

•

VAXft Model 612 Dual-Node VAXcluster Entry System

•

VAXft Model 612 Dual-Node VAXcluster Expanded System

Each configuration is described in detail in the following sections, but some
features and options are available and common to all configurations. These
common features and options are described in Section 2.1

2.1 Common Features and Options for Configuring VAXft
Systems
Every VAXft system has two zones each of which has a backplane for logic
modules. Each zone in the Model 110 backplane has five slots, while all
the other systems have seven-slot backplanes. Figure 2–1 and Figure 2–2
show the placement in the backplane of the required modules: processor,
memory, and system I/O controller for Ethernet/DSSI /console connections.
If an additional system I/O controller is needed, the first slot is used on the
seven-slot backplane and the fourth or fifth on the five-slot backplane.

VAXft Systems Configurations and Options 2–1

Figure 2–1 Seven-Slot Backplane

1 2 3 4 5 6 7

E C M
N P E
E U M
T
O
/
R
D
Y
S
S
I

1 2 3 4 5 6 7

E C M
N P E
E U M
T
O
/
R
D
Y
S
S
I

Crosslink Cables
MR-5525-AD

2–2 VAXft Systems Configurations and Options

Figure 2–2 Five-Slot Backplane

1 2 3 4 5

E C M
N P E
E U M
T
O
/
R
D
Y
S
S
I

Crosslink Cables
MR-5526-AD

Most of the options for memory, mass storage, and buses are common to all
the systems. Table 2–1 gives each of the options, their capacities, and model
numbers.
Table 2–1 Common Options for the VAXft Systems
Model
Number

Option

Description

Tape Drive

TF70C 290-megabyte cartridge tape drive.

TF70C-RA,
TF70C-JA,
TF70C-AA

Tape Loader

TF857 18.2-gigabyte tape loader for unattended
backup (available on Models 610/612 only). The
TF857 can contain up to seven cartridge tapes.
Normally, TK85K 2.1-gigbyte tapes are used, but
TF70C and other cartridge tapes can also be used.

TF857-CA

(continued on next page)

VAXft Systems Configurations and Options 2–3

Table 2–1 (Cont.) Common Options for the VAXft Systems
Option

Description

Disk Storage

RF-series Integrated Storage Elements:
RF31 381-megabyte fixed disks
RF31 381-megabyte shock-mounted removable
disks
RF72 1-gigabyte fixed disk
RF72 1-gigabyte shock-mounted removable
disk

Model
Number
RF31E-RA,
RF31-KA,
RF31-JA,
RF72E-RA,
RF72-KA,
RF72-JA

Memory Module

The minimum system for each model comes
with one 32-megabyte memory module per zone.
Memory capacity must be identical in both zones.

MS520-BB

System I/O controller
module

Connections to Ethernet and DSSI bus.

KFE52-AA

DEC WANcontroller 620

The two-line synchronous communication controller
for the VAXft systems. The WAN module supports
connections to X.25, DECnet, and IBM networks
with appropriate Digital Equipment Corporation
networking layered product software.

DSF32-AA

Console Terminal Ports

One local console and one remote console port is
included in each zone for a total of four console
ports per system.
Order two video terminals such as VT420s
unless otherwise available. A combination of
video terminal and LA75 printer/terminal is
recommended. You must have a minimum of
two console terminals to support fault-tolerant
operation.

Uninterrruptable Power
Supply (UPS)

A battery backup option (in-cabinet) for each zone
is included in Models 310/410/610/612. A battery
backup option (out of cabinet) for each zone must
be added for the Model 110 if UPS is required for
in-cabinet components or external devices such as
servers, printers, and modems.

H7229-AD

Each VAXft system that has a DC power supply (see the configuration
illustrations) has a Power Cooling Intelligence Module (PCIM) incorporated
into the DC power supply. When such a system is expanded, a PCIM cable
must connect the PCIMs in each DC pwer supply. The illustrations of the
expanded systems show this cable.

2–4 VAXft Systems Configurations and Options

Although a tape drive or tape loader is not required for any VAXft system,
Digital strongly recommends that you purchase one for backup. If you have a
need for large amounts of unattended tape backup on a Model 610 or 612, the
TF857 tape loader is the recommended tape option. It has a capacity of up to
18.2 gigabytes of storage in up to seven tape cartridges.
In most expanded VAXft systems, the disk mass storage is located in the
expansion cabinets in the form of fixed disks. However, one removable disk is
allowed as long as fixed disk unit 4 is not used. In the Model 310/410, you can
have a tape drive instead of the removable disk, but the tape drive would still
replace fixed disk unit 4. On Models 610 and 612, the optional tape drives are
separate from the optional removable disk; in this case, the tape drive replaces
fixed disk unit 5 in the expansion cabinet. So, if in an expanded system, you
want a removable disk and/or a tape drive (depending on model), you should
order one or two fewer fixed disk drives. Figure 2–3 shows the disk units that
are replaced by removable disks and/or tapes.

VAXft Systems Configurations and Options 2–5

Figure 2–3 Disk Units

Sum
m
Pan ary
el

4
Tap

Exp

ansi

Rem 5
ov
Diskable

Zon
e
ACA
Box

nclo

sure

e
DC
Pow
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A
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Fixe
4
Diskd Fix
ed
Disk

Fixe
Diskd Fix 2
e
Diskd

Fixe
Diskd Fix 0
e
Diskd

MR-5524-AD

2.2 The VAXft Model 110 System
The VAXft Model 110 system is the minimum VAX fault-tolerant system
configuration available from Digital Equipment Corporation. This system
features low cost with limited mass storage. It can be purchased as a rackmounted system or a pedestal system. Both zones of the Model 110 system
are contained in a single cabinet. Each zone contains a five-slot backplane,
connectors, and mass storage. Figure 2–4 shows the configuration of the VAXft
Model 110 system.

2–6 VAXft Systems Configurations and Options

Figure 2–4 VAXft Model 110 Configuration
Zon

Disk

Zon
Disk

AP
CoS
u
wp
ep
r l
y

Fan

Disk

C
P
U

Disk Disk
or
Tap
e

AP
CoS
u
wp
ep
r l
Cros
slink
Cab y
les

C
P
U

Fan

MR-5494-AD

2.2.1 VAXft Model 110 Mass Storage and Module Options
The Model 110 supports a maximum of six DSSI mass storage devices, up
to three devices in each zone. All mass storage devices are contained in
the system enclosure as shown in Figure 2–4. Mass storage devices can be
configured with RF31 fixed disks, RF72 fixed disks, and TF70C cartridge tape
in the one of the following combinations:
•

Three RF31 disks in each zone for a total of six RF31 disks

•

Three RF31 disks in zone A and two RF31 disks plus one TF70C tape in
zone B for a total of five RF31 disks and one TF70C tape

•

Two RF72 disks in each zone for a total of four RF72 disks

•

Two RF72 disks in zone A and one RF72 disk plus one TF70C tape in zone
B for a total of three RF72 disks and one TF70C tape

Figure 2–4 shows the mass storage configuration with three RF31 disks in
each zone of the VAXft Model 110 system.
Table 2–2 gives the minimum and maximum system components for the Model
110 system.

VAXft Systems Configurations and Options 2–7

Table 2–2 Module Options for the Model 110
Model
Number

Option

Description

Tape Drive

Cartridge tape drive. One is optional for Zone B; a
maximum of one tape drive can be ordered.

TF70C-RA

Disk Storage

RF31 or RF72 fixed disk drive. The minimum
system comes without disks, but disks are a
required option. RF31s and RF72s cannot be
mixed on the Model 110.

RF31E-RA,
RF72E-RA

Memory Module

A minimum of one and a maximum of two memory
modules can be configured per zone. Memory
capacity must be identical in both zones.

MS520-BB

System I/O controller
module

The system comes with one system I/O controller
module per zone to provide Ethernet lines and
DSSI lines. An additional system I/O controller
module can be added in each zone to provide
redundant connections to dual Ethernet lines. (An
additional DSSI is not available.)

KFE52-AA

DEC WANcontroller 620

A maximum of four WAN modules (two per zone)
can be configured to give eight synchronous, nonredundant lines per system.

DSF32-AA

Console Terminal Ports

One local console and one remote console port is
included in each zone for a total of four console
ports per system.

Uninterrruptable Power
Supply (UPS)

A battery backup option (out of cabinet) for each
zone must be added if UPS is required for incabinet components or external devices such as
servers, printers, and modems.

H7229-AD

2.3 VAXft Model 310/410 Entry System
The VAXft Model 310 and the VAXft Model 410 entry systems are identical
in everything but the processor. The Model 310 processor has 3.8 VUPs
of processing power, while the Model 410 has 6.0 VUPs. To upgrade from
a VAXft Model 310 system to a VAXft Model 410 system requires merely
the replacement of the Model 310 processor with the Model 410 processor.
Unlike the Model 110, the Model 310/410 is expandable (see Section 2.4). The
Model 310/410 entry system is recommended if your requirements for online
non-shadowed disk storage do not exceed 3 gigabytes.

2–8 VAXft Systems Configurations and Options

A Model 310/410 entry system configuration includes two zones, each
containing a seven-slot backplane, connectors, and mass storage. Refer to
Figure 2–5 for an illustration of the system components.
Figure 2–5 VAXft Model 310/410 Entry System Configuration

Zon

Disk
or
Tap
e
D
Po C
Supwer
ply
A
Po C
Supwer
ply

B
B
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Disk
Zon

Log

ic M
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C
P
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Lo
Concal and
sole
ConRemote
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ions

Cros

slink

Cab

les

MR-5493-AD

2.3.1 VAXft Model 310/410 Entry System Mass Storage and Module
Options
The Model 310/410 entry system supports a maximum of four DSSI mass
storage devices, two devices in each cabinet. All mass storage devices are
contained in the system cabinets. All storage devices are removable. Mass
storage devices can be configured in the following combinations:
•

Four RF31/RF72 disks

•

three RF31/RF72 disks and one TF70C tape drive

•

two RF31/RF72 disks and two TF70C tape drives

VAXft Systems Configurations and Options 2–9

•

two RF31/RF72 disks and one TF70C tape drive

Figure 2–5 shows the disk configuration for the Model 310/410 entry system,
including a tape drive and three disks.
If one zone is down due to planned maintenance or repair, the mass storage
devices contained in that zone are unavailable to the operational zone. Shadow
set members in the downed zone must be updated when the zone is returned
to operation. Refer to Section 1.3.2.1, Guidelines for Shadowing Data, for more
details.
Table 2–3 gives the minimum and maximum system components available for
the Model 310/410 entry system.
Table 2–3 Module Options for the Model 310/410 Entry System
Model
Number

Option

Description

Tape Drive

Cartridge tape drive. a maximum of two tape
drives can be ordered.

TF70C-JA

Disk Storage

RF31 or RF72 removable disk drive. The minimum
system comes with two RF disks. One or two
additional optional RF drives can be added to the
system for a maximum of four RF disk drives.

RF31-JA,
RF72-JA

Memory Module

A minimum of one and a maximum of four memory
modules per zone can be configured. Memory
capacity must be identical in both zones.

MS520-BB

System I/O controller
module

KFE52-AA

DEC WANcontroller 620

A maximum of eight WAN modules (four per zone)
can be configured per system.

DSF32-AA/AB

Console Terminal Ports

One local console and one remote console port is
included in each zone for a total of four console
ports per system.

2.4 VAXft Model 310/410 Expanded System
The VAXft Model 310 and the VAXft Model 410 expanded system provides up
to 12 gigabytes of non-shadowed mass storage with dual-access to disks from
both zones at all times. Figure 2–6 shows the Model 310/410 expanded system
configuration.

2–10 VAXft Systems Configurations and Options

A
Po C
Supwer
ply

D
Po C
Supwer
ply

Disk
or
Tap
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B
B
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Exp

PCIM

Re
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Op
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ure

clos

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Op
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losu

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B
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Cab

CPU

PCIM

ure

Enc
los

DSS
I

Zon
eB

Exp
ansio
n

ure

Enc
los

MR-5495-AD

Figure 2–6 Model 310/410 Expanded System Configuration

VAXft Systems Configurations and Options 2–11

The Model 310/410 expanded system consists of two system cabinets and two
expansion cabinets. The system cabinets are similar to the Model 310/410
entry system, but they contain no mass storage options. Each zone contains
a seven-slot backplane and connectors. The expansion cabinets connect to the
system cabinets by dual DSSI buses; this enables access to mass storage by
both zones.

2.4.1 VAXft Model 310/410 Expanded System Mass Storage and Module
Options
All mass storage devices for the Model 310/410 expanded system must be
configured inside the expansion cabinets. Each expansion cabinet holds up to
six DSSI storage devices for a total of 12 devices per system. Most disk drives
are fixed, but an optional tape drive or removable disk drive can replace one
of the fixed drives. See Figure 2–3 and accompanying text. Configure mass
storage devices in each expansion cabinet in the following combinations:
•

Up to five RF31/RF72 fixed disk drives and one TF70C tape drive

•

Up to six RF31/RF72 fixed disk drives

•

Up to five RF31/RF72 fixed disk drives and one RF31/RF72 removable disk

Two RF31/RF72 fixed disk drives are the minimum required mass storage for
the Model 310/410 expanded system; a tape device is highly recommended for
backup.
Figure 2–6 shows dual access to mass storage devices by either zone at all
times, even when one zone is not operational. A pair of system I/O controller
adapters in each zone interface the system with the dual DSSI buses, so even
the loss of a single zone does not deny the system access to both members of a
shadow set. To optimize overall system availability, the primary member of a
shadow set must reside on one DSSI bus. The shadowed member should reside
on the other DSSI bus.
Table 2–4 gives the minimum and maximum system components for the Model
310/410 expanded system.

2–12 VAXft Systems Configurations and Options

Table 2–4 Options Table for Model 310/410 Expanded System
Model
Number

Option

Description

Tape Drive

Cartridge tape drive. a maximum of two
tape drives can be ordered.

TF70C-JA

Disk Storage

RF31 or RF72 fixed or removable disk
drive. The minimum system comes with
two RF fixed disks. Maximum of 12 RF
fixed disk drives allowed per system. Only
one RF removable disk is allowed per zone.

RF31-KA,
RF31-JA,
RF72-KA,
RF72-JA

Memory Module

A minimum of one and a maximum of
four memory modules per zone can be
configured. Memory capacity must be
identical in both zones.

MS520-BB

System I/O controller
module

The system comes with two system I/O
controller modules per zone to provide
Ethernet lines and DSSI lines.

KFE52-AA

DEC WANcontroller 620

A maximum of eight WAN modules (four
per zone) can be configured for a maximum
of 16 synchronous lines per system.

DSF32-AA/AB

Console Terminal Ports

One local console and one remote console
port is included in each zone for a total of
four console ports per system.

2.5 VAXft Model 610 Entry System
The Model 610 entry system is a fault-tolerant system available in a 60-inch
cabinet with one zone on top of the other, rather than side-by-side. The
Model 610 entry system is recommended if your requirements for online
non-shadowed storage do not exceed 3 gigabytes. The Model 610 is expandable
(see Section 2.6).
A Model 610 entry system configuration includes one system cabinet,
containing two zones, each containing a seven-slot backplane, connectors,
and mass storage. Refer to Figure 2–7 for an illustration of the system
components.

VAXft Systems Configurations and Options 2–13

Figure 2–7 Model 610 Entry System Configuration

Zon

Op
Diskt
D
Po C
Supwer
ply

B
B
U

Re
Disqk

Sum
m
Pan ary
el

Log

ic M
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C
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A
Po C
Supwer
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Op
Tapt
e

DSS

Zon
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ACA
Box

Op
Diskt
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A
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B
B
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Log

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C
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Op
Tapt
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DSS

Zon

Zon
e
ACB
Box
MR-5504-AD

2.5.1 VAXft Model 610 Entry System Mass Storage and Module Options
The Model 610 entry system supports a maximum of six DSSI mass storage
devices, three devices in each zone. All mass storage devices are contained in
the system cabinet. All storage devices are removable. Mass storage devices
can be configured in the following combinations:
•

Six RF31/RF72 disks

•

Five RF31/RF72 disks and one TF70C/TF857 tape drive

2–14 VAXft Systems Configurations and Options

•

Four RF31/RF72 disks and two TF70C/TF857 tape drives

Figure 2–7 shows a full disk configuration for the Model 610 entry system,
including a tape drive, a tape loader, and four disks.
If one zone is down due to planned maintenance or repair, the mass storage
devices contained in that zone are unavailable to the operational zone. Shadow
set members in the downed zone must be updated when the zone is returned
to operation. Refer to Section 1.3.2.1, Guidelines for Shadowing Data, for more
details.
Table 2–5 gives the minimum and maximum system components for the Model
610 entry system.
Table 2–5 Module Options for the Model 610 Entry System
Model
Number

Option

Description

Tape Drive

Cartridge tape drive; maximum of two tape drives
can be ordered.

TF70C-AA

Tape Loader

TF857 tape loader for unattended backup. A tape
loader can replace one or both TF70C tape drives.

TF857-CA

Disk Storage

RF31 or RF72 shock-mounted removable disk
drive. The minimum system comes with two RF
disks. Two additional optional RF drives can be
added to the system for a maximum of four RF
disk drives.

RF31-JA,
RF72-JA

Memory Module

A minimum of one and a maximum of four memory
modules per zone can be configured. Memory
capacity must be identical in both zones.

MS520-BB

System I/O controller
module

System comes with one system I/O controller
module per zone to provide Ethernet lines and
DSSI lines. An additional system I/O controller
module can be added in each zone to provide
redundant connections to dual Ethernet lines.

KFE52-AA

DEC WANcontroller 620

The two-line synchronous communication controller
for VAXft systems. A maximum of eight WAN
modules (four per zone) can be configured for a
total of 16 synchronous, non-redundant lines per
system.

DSF32-AA/AB

(continued on next page)

VAXft Systems Configurations and Options 2–15

Table 2–5 (Cont.) Module Options for the Model 610 Entry System
Option

Description

Console Terminal Ports

One local console and one remote console port is
included in each zone for a total of four console
ports per system.

Model
Number

2.6 VAXft Model 610 Expanded Systems
The Two Model 610 expanded systems are available (as shown in Figure 2–8
and Figure 2–9) to provide up to 24 gigabytes of non-shadowed mass storage
with dual-access to disks from both zones at all times.

2–16 VAXft Systems Configurations and Options

Figure 2–8 Model 610 Expanded System Configuration with One Expansion Cabinet

Zon

N
Ava ot
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A
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on E

B
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Op
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MR-5505-AD

VAXft Systems Configurations and Options 2–17

2–18 VAXft Systems Configurations and Options
A
Po C
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PCI

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ure

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MR-5506-AD

Figure 2–9 Model 610 Expanded System Configuration with Two Expansion
Cabinets

The Model 610 expanded systems consist of the single system cabinet plus
one or two expansion cabinets. The system cabinet is similar to the Model
610 entry system, but it contains no disk drives. It can contain one or two
TF70C/TF857 tape drives. Each zone contains a seven-slot backplane for a
processor module, a memory module, and two or four system I/O controller
modules for DSSI/Ethernet interfaces. The system with the single expansion
cabinet requires two system I/O controller modules (in slots 1 and 2), while
the system with the two expansion cabinets requires four system I/O controller
modules (in slots 1, 2, 6, and 7). Figure 2–8 and Figure 2–9 show the slots that
the DSSI buses use.
Like the system cabinet, each expander cabinet contains two zones one on top
of the other. Each zone contains its own power supply (AC, DC, and battery)
and can contain up to six disk drives.

2.6.1 VAXft Model 610 Expanded Systems Mass Storage and Module
Options
All disk storage devices for the Model 610 expanded systems must be
configured inside the expansion cabinets. Each expansion cabinet holds up to
12 disk drives (six per zone) for a total of 12 disk drives for an expanded system
with one enclosure cabinet and 24 disk drives for one with two expansion
cabinets. The expansion cabinets connect to the system cabinet by dual DSSI
buses; this enables access to mass storage by both zones. Configure mass
storage devices in a system with a single expansion cabinet in the following
combinations:
•

Up to 12 RF31/RF72 fixed disks.

•

10 or 11 RF31/RF72 fixed disks and one or two TF70C/TF857 tape drives.

•

11 RF31/RF72 fixed disks and one RF31/RF72 removable disk.

Two RF31/RF72 fixed disks are the minimum requirement for mass storage for
the Model 610 expanded system with one expansion cabinet.
Configure mass storage devices in a system with dual expansion cabinets in
the following combinations:
•

Up to 24 RF31/RF72 fixed disks.

•

22 or 23 RF31/RF72 fixed disks and one or two TF70C/TF857 tape drives.

•

22 or 23 RF31/RF72 fixed disks and one or two RF31/RF72 removable
disks.

Four RF31/RF72 fixed disks are the minimum requirement for mass storage
for the Model 610 expanded system with dual expansion cabinets.

VAXft Systems Configurations and Options 2–19

Figure 2–8 and Figure 2–9 show dual access to mass storage devices by either
zone at all times, even when one zone is not operational. A pair of system
I/O controller adapters in each zone interface the system with the dual DSSI
buses, so even the loss of a single zone does not deny the system access to both
members of a shadow set. To optimize overall system availability, the primary
member of a shadow set must reside on one DSSI bus. The shadowed member
should reside on the other DSSI bus.
Table 2–6 gives the minimum and maximum system components available for
the Model 610 expanded systems.
Table 2–6 Options Table for Model 610 Expanded Systems
Model
Number

Option

Description

Tape Drive

Cartridge tape drive; a maximum of two
tape drives can be ordered.

TF70C-AA

Tape Loader

TF857 tape loader for unattended backup.
A tape loader can replace one or both
TF70C tape drives.

TF857-CA

Disk Storage

RF31 or RF72 fixed and removable disk
drives. A minimum of two RF fixed disk
drives are required. Maximum of 12 RF
disk drives allowed per expansion cabinet.
Only one RF removable disk is allowed per
expansion cabinet.

RF31-KA,
RF31-JA,
RF72-KA,
RF72-JA

Memory Module

A minimum of one and a maximum of
four memory modules per zone can be
configured. Memory capacity must be
identical in both zones.

MS520-BB

DEC WANcontroller 620

A maximum of six modules (three per
zone) can be configured to give 12
synchronous lines for a system with one
expansion cabinet. A maximum of two
modules (one per zone) can be configured
to give four synchronous lines for a system
with two expansion cabinets.

DSF32-AA/AB

Console Terminal Ports

Two local console ports and two remote
console ports are included per system.

2–20 VAXft Systems Configurations and Options

2.7 VAXft Model 612 Entry VAXcluster System
The VAXft Model 612 entry VAXcluster system is a dual-node fault-tolerant
VAXcluster system consisting of two VAXft Model 610 systems sharing a
single expansion cabinet that contains the DSSI disk devices. The Model 612
VAXcluster system has 12 VUPs of processing power, twice that of a Model 610
system. The Model 612 is expandable (see Section 2.8).
A Model 612 entry VAXcluster system configuration includes two Model 610
systems, each containing two zones with a seven-slot backplane in each zone
and optional tape storage. Refer to Figure 2–10 for an illustration of the
system components.

VAXft Systems Configurations and Options 2–21

2–22 VAXft Systems Configurations and Options
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MR-5508-AD

Figure 2–10 VAXft Model 612 Entry VAXcluster Configuration

2.7.1 VAXft Model 612 Entry VAXcluster Mass Storage and Module
Options
The Model 612 entry VAXcluster system supports a maximum of 12 disk
drives in the expansion cabinet and two tape drives in each zone in the Node
1 system cabinet (as shown in Figure 2–10). No storage devices are available
in the Node 2 system cabinet. Mass storage devices can be configured in the
following combinations:
•

Twelve RF31/RF72 fixed disks

•

10 or 11 RF31/RF72 fixed disks and one or two TF70C/TF857 tape drives

•

10 or 11 RF31/RF72 fixed disks and one or two RF31/RF72 removable disks

•

Eight or nine RF31/RF72 fixed disks and one or two RF31/RF72 removable
disks plus one or two TF70C/TF857 tape drives

A minimum of two RF fixed disks is required for the system, and it is
recommended that at least one TF tape drive be added for backup.
Figure 2–10 shows a full disk configuration for the Model 612 entry VAXcluster
system, including a tape drive, a tape loader, and ten disks.
If one zone in a node is down due to planned maintenance or repair, the mass
storage devices contained in that zone are unavailable to the operational zone.
Shadow set members in the downed zone must be updated when the zone is
returned to operation. Refer to Section 1.3.2.1, Guidelines for Shadowing Data,
for more details.
Table 2–7 gives the minimum and maximum system components for the Model
612 entry VAXcluster system.
Table 2–7 Module Options for the Model 612 Entry VAXcluster System
Model
Number

Option

Description

Tape Drive

Cartridge tape drive; maximum of two tape drives
can be ordered.

TF70C-AA

Tape Loader

TF857 tape loader for unattended backup. A tape
loader can replace one or both TF70C tape drives.

TF857-CA

(continued on next page)

VAXft Systems Configurations and Options 2–23

Table 2–7 (Cont.) Module Options for the Model 612 Entry VAXcluster System
Model
Number

Option

Description

Disk Storage

RF31 or RF72 fixed or removable disk drive. The
minimum system comes with two RF fixed disks
and can have a maximum of 12 RF fixed disk
drives. A maximum of two RF removable disks can
be configured, replacing two RF fixed drives.

RF31-KA,
RF31-JA,
RF72-KA,
RF72-JA

Memory Module

A minimum of one and a maximum of four memory
modules per zone per node can be configured.
Memory capacity must be identical in both zones of
a node.

MS520-BB

System I/O controller
module

Each node comes with one system I/O controller
module per zone to provide Ethernet lines and
DSSI lines, and Node 1 has an additional I/O
controller per zone for a tape drive. An additional
system I/O controller module can be added in each
zone in each node to provide redundant connections
to dual Ethernet lines.

KFE52-AA

DEC WANcontroller 620

The two-line synchronous communication controller
for VAXft systems. A maximum of eight WAN
modules (four per zone) can be configured for each
node for a total of 16 synchronous, non-redundant
lines per node.

DSF32-AA/AB

Console Terminal Ports

One local console and one remote console port is
included in each zone for a total of four console
ports per node.

2.8 VAXft Model 612 Expanded VAXcluster System
The VAXft Model 612 expanded VAXcluster system offers the maximum
fault-tolerant system configuration currently available. It provides up to 24
gigabytes of non-shadowed mass storage with dual-access to disks from both
zones at all times as well as shared access to disks from both nodes.
The Model 612 expanded VAXcluster system consists of two Model 610 systems
sharing the disks in two expansion cabinets as shown in Figure 2–11.

2–24 VAXft Systems Configurations and Options

Figure 2–11 VAXft Model 612 Expanded VAXcluster Configuration

VAXft Systems Configurations and Options 2–25

Each node is a Model 610 system without disk drives, which are contained
in the expansion cabinets. Node 1 can contain one or two TF70C/TF857
tape drives. Each zone in each node contains a seven-slot backplane for a
processor module, a memory module, and two system I/O controller modules
for DSSI/Ethernet interfaces.
Like the system cabinets, each expander cabinet contains two zones one on top
of the other. Each zone contains its own power supply (AC, DC, and battery)
and can contain up to six disk drives.

2.8.1 VAXft Model 612 Expanded VAXcluster System Mass Storage and
Module Options
All disk storage devices for the Model 612 expanded VAXcluster system must
be configured inside the expansion cabinets. Each expansion cabinet holds
up to 12 disk drives (six per zone) for a total of 24 disk drives. The expansion
cabinets connect to the system cabinets by dual DSSI buses; this enables access
to mass storage by both zones.
Configure mass storage devices in a Model 612 expanded VAXcluster system in
the following combinations:
•

Up to 24 RF31/RF72 fixed disks.

•

22 or 23 RF31/RF72 fixed disks and one or two TF70C/TF857 tape drives.

•

22 or 23 RF31/RF72 fixed disks and one or two RF31/RF72 removable
disks.

Four RF31/RF72 fixed disks are the minimum requirement for mass storage
for the Model 612 expanded VAXcluster system.
Figure 2–11 shows dual access to mass storage devices by either zone in each
node at all times, even when one zone is not operational. A pair of system
I/O controller adapters in each zone interface the system with the dual DSSI
buses, so even the loss of a single zone does not deny the system access to both
members of a shadow set. To optimize overall system availability, the primary
member of a shadow set must reside on one DSSI bus. The shadowed member
should reside on the other DSSI bus.
Table 2–8 gives the minimum and maximum system components available for
the Model 612 expanded VAXcluster system.

2–26 VAXft Systems Configurations and Options

Table 2–8 Options Table for Model 612 Expanded VAXcluster System
Model
Number

Option

Description

Tape Drive

Cartridge tape drive; a maximum of two
tape drives can be ordered.

TF70C-AA

Tape Loader

TF857 tape loader for unattended backup.
A tape loader can replace one or both
TF70C tape drives.

TF857-CA

Disk Storage

RF31 or RF72 fixed and removable disk
drives. A minimum of four RF fixed disk
drives are required. A maximum of 12
RF disk drives are allowed per expansion
cabinet. Only one RF removable disk is
allowed per expansion cabinet.

RF31-KA,
RF31-JA,
RF72-KA,
RF72-JA

Memory Module

A minimum of one and a Maximum of four
memory modules per zone per node can
be configured. Memory capacity must be
identical in both zones.

MS520-BB

System I/O controller
module

Each node comes with two system I/O
controller modules per zone to provide
Ethernet lines and DSSI lines. An
additional system I/O controller module
can be added in each zone in each node
to provide redundant connections to dual
Ethernet lines.

KFE52-AA

DEC WANcontroller 620

A maximum of six modules (three per
zone) can be configured to give 12
synchronous lines per node.

DSF32-AA/AB

Console Terminal Ports

Two local console ports and two remote
console ports are included per node.

2.9 Upgrading A VAXft Model 610 System to a VAXft Model
612 System
Because a VAXft Model 612 system is a VAXcluster system consisting of two
VAXft Model 610 systems, it is not difficult to upgrade the Model 610 system.
You will need another Model 610 system cabinet without disks plus one or
two expansion cabinets to configure a Model 612 VAXcluster system. You will
probably need at least one additional system I/O controller module per zone in
each node and additional disk drives.

VAXft Systems Configurations and Options 2–27

2.10 Summary of System Configuration Characteristics
Key configuration characteristics of the VAXft systems include:
•

Two types of systems

•

Redundancy of all system components

•

Four types of system modules

•

Redundant backplanes

•

Up to 128 megabytes of memory (32-megabyte increments)

•

Up to 16 synchronous communication lines (without redundancy)

•

Up to 8 synchronous communication lines (with redundancy)

•

Single or dual Ethernet fault-tolerant connections

•

Up to 24 DSSI mass storage devices (expanded systems)

•

VMS Volume Shadowing

•

Up to four console ports (one local and one remote per zone) per system

2–28 VAXft Systems Configurations and Options

3
Networking Communications
As the industry leader in networking, Digital Equipment Corporation is able to
provide extensive communications options for the VAXft systems.
These communications options enable the VAXft systems to be configured in
Local Area Networks (LANs) and Wide Area Networks (WANs).
Networking options include:
•

Ethernet connections

•

Synchronous communication options

3.1 Ethernet Connections
The ability to connect to the Ethernet enables the VAXft systems to use
certain networking options available from Digital Equipment Corporation.
Ethernet, the industry standard Local Area Network, enables VAXft systems to
communicate with other computers in your enterprise.
The VAXft systems support redundant connections to a single Ethernet or
to dual Ethernets. The Ethernet interface is in the DSSI/Ethernet/Console
I/O module. This module supports both thick wire and ThinWire connections
between the system and Ethernet.
Figure 3–1 shows two connections to a single Ethernet segment, one connection
from each zone of the system.

Networking Communications 3–1

Figure 3–1 System Configured to Single Ethernet
Terminal

VT320

Terminal
Server

DECserver 300
d i g i t a l

Ethernet

d i g i t a l

VAX ft 3000

d i g i t a l

VAX ft 3000

VAXft System
MR-5519-AD

Figure 3–2 shows redundant connections to two Ethernets. This ensures access
to Ethernet even if one connection is not working.
Redundant connections to dual Ethernets, as shown in Figure 3–2, require
two system I/O controller modules in each zone for a total of four controllers
system-wide. This means there is one I/O module in each zone connected to
each Ethernet at all times.

3–2 Networking Communications

Figure 3–2 System Configured to Dual Ethernet

Terminal
Server

Terminal

VT320

DECserver 300

d i g i t a l

Terminal
Server

Ethernet

d i g i t a l

VAX ft 3000

d i g i t a l

VAX ft 3000

VAXft System
MR-5520-AD

3.2 DECserver Terminal Servers
Terminal servers provided by Digital Equipment Corporation for use with the
VAXft systems include a variety of DECserver systems to provide asynchronous
communications.
Terminal servers provide system users with easy, transparent access to VAXft
system resources. Figures 3–1 and 3–2 illustrate how terminal servers are
used to connect user terminals to the system through the Ethernet. Terminal
servers, connected to the system through Ethernet, enable users to establish
and maintain several simultaneous sessions on system processors without
delay, as long as sufficient resources are available. Figure 3–2 shows how the
terminals as well as the servers can be configured redundantly so that a user
can switch to another server if one goes down.

Networking Communications 3–3

For more information on terminal servers used with the VAXft systems, see the
VAX Systems/DECsystems Systems and Options Catalog and the Networking
and Communications Buyers Guide.

3.3 Synchronous Communications
DEC WANcontroller 620
The DEC WANcontroller 620 is a two-line synchronous communication
controller option specifically designed for VAXft systems. The WAN module
can be configured to provide highly-available synchronous communication. The
VAXft systems supportup to four WAN modules in each zone (eight per system).
Each module contains two lines; thus, eight redundant or 16 nonredundant
synchronous lines can be supported by a single VAXft system, with full modem
control. Lines attached to redundant controllers are connected by Y-connectors
that enable a single synchronous line to be connected to an adapter in each
zone, as shown in Figure 3–3.
Ethernet Servers
Expanded synchronous communications are supported through Ethernet-based
Gateways or Microservers. Refer to the Networks and Communications Buyer’s
Guide for further details on networking options.

3–4 Networking Communications

Figure 3–3 Synchronous Communication Lines Using Y-Connectors

Tape
Drive

Disk

Disk
or
Tape

Disk

1 2 3 4 5 6 7

E C M C
T P E O
H U MM
E
OM
R
R
N
Y
E
T

Crosslink Cables
Ethernet

Y-connector
Synch
Lines

Y-connector
Synch
Lines
MR-5522-AD

3.4 Summary of System Communication Characteristics
Key characteristics of the VAXft system networking features include:
•

Dual Ethernet connections, including redundant connections

•

Up to 16 nonredundant synchronous communication lines

•

Up to eight redundant synchronous communication lines

Networking Communications 3–5

•

Support of DECserver terminals to connect user terminals to the system
through the Ethernet

•

Support of Gateways and Microservers

3–6 Networking Communications

4
System Service and Warranty
4.1 Service and Repair Features
The VAXft systems’ design makes them easier to repair and maintain than
other types of fault-tolerant computers.
The dual zone design enables repairs without interruption to a running
application because the system’s redundant hardware enables the operational
zone to continue to service the application while repairs are made to the zone
that has been shut down. Each zone displays a flashing red light to identify a
failure in the zone. Logic modules have Magnetic Fault Indicators (MFI) that
provide visual indication of a fault.
All the contents of each cabinet are accessible from the front. Dual doors allow
easy operator access.
To expedite repairs even further, the system can automatically notify the user
by automatic dialout notification. The system’s modular system design makes
repair as easy as manually removing the Field Replaceable Unit (FRU) and
replacing it with a new unit.
When you combine all of these features, you can be sure that the VAXft
systems provide the fastest and most accurate repair and service available for
any fault-tolerant computer today.
Automatic dialout notification is Digital Equipment Corporation’s proactive
approach to resolving system problems before they lead to failures.
Depending on your requirements, automatic dialout notification can send a
message to an operator on site or to a remote terminal using a predefined
telephone number and a modem. This feature can also be utilized to
automatically place a service call to Digital Customer Support when the system
is experiencing a problem or the system exceeds a predictive maintenance
threshold.

System Service and Warranty 4–1

4.2 System Warranty
The following warranties are available for the VAXft systems:
•

Standard Warranty

•

List Warranty

4.2.1 Standard Warranty
The standard warranty available for the VAXft systems includes:
•

Hardware installation

•

One-year DECservice for hardware, 24-hour, 7-day a week coverage,
including holidays, with a committed response time

•

Telephone assistance for hardware, operating system software, and Digital
layered products purchased with the Standard Warranty

•

Critical on-site software support

•

Digital Software Information Network

•

Right-to-use new versions of software

•

Product Foundation Warranty for kernel software

4.2.2 List Warranty
The List Warranty available for the VAXft systems includes: 1-year return to
factory for all hardware and software conformance.

4.3 Digital Assisted Services Program
The Digital Assisted Services Program (DASP), which provides selfmaintenance customers with selected products and services under an annuity
payment schedule, is available for the VAXft systems.
The DASP is a four-part program that includes:
•

Diagnostics and documentation
This includes licensing of diagnostics, media and documentation kits for
diagnostics, hardcopy manuals and print sets, maintenance documentation
service (including DEC-O-Log), and rights-to-copy.

•

Diagnostic and documentation updates
This includes media and documentation kits, microfiche for hardcopy
documentation, and rights-to-copy.

•

DECmailer and Field Change Orders

4–2 System Service and Warranty

This includes DECmailer Plus board repair for a 24-hour turnaround
time, emergency dispatch service at no extra charge, all repairable boards
accepted regardless of revision, unlimited number of boards repaired. Field
Change Orders include the same services as DECservice customer and
materials only (customer installs).
•

Customer Support Centers
Customer Support Centers provide 24-hour, 7-day a week, access to remote
diagnostic and remote support groups. In addition, use of service delivery
tools, such as VAXsim Plus and SPEAR, is included.

A subscriber to DASP can also purchase spare parts and kits, internal
customer services training, and backup support on a per-call basis.

4.4 Summary of System Service and Repair Features
The VAXft maintenance and repair features provide the following benefits:
•

All system repairs can be performed without interrupting the application.

•

Dual zone design helps avoid human error during service.

•

Modular design enables easy removal and replacement of failed components
without the use of special tools.

•

All system components are easily accessible from the front of the system.

•

Zones display red flashing fault indicators to identify failed zones.

•

Magnetic indicators identify failed FRUs.

•

Dual doors enable access only to selected system components.

•

Automatic dialout to expedite notification upon the occurrence of a failure.

•

VAXsimPLUS identifies, locates, and prepares diagnostic reports on
failures. VMS error logger logs errors. VAXsimPLUS monitors the system
error log for hard and soft errors.

System Service and Warranty 4–3

Glossary
The following is a list of commonly used terms used in this guide.
automatic dialout notification
The process of sending a message to a specific remote site using a modem and
a predefined telephone number to alert personnel of a system fault or failure.
autonotification
Automatic dialout notification.
Availability
The likelihood that the system will be operable when you require it to perform
a task.
boot or bootstrap
The process of loading system software into a processor’s main memory.
CPU
Central Processing Unit.
crosslink
The cable that connects two VAXft 3000 zones together to form a fault-tolerant
system.
CVAX
A 32-bit VAX virtual memory instruction set processor implemented in CMOS.
DEC WANcontroller 620
Digital Equipment Corporation’s Wide Area Network controller.

Glossary–1

DMA
Direct Memory Access. The hardware that transfers data between VAXft main
memory and the buffer memory on the I/O modules.
DSSI (Digital Storage Systems Interconnect)
A data bus that uses the System Communication Architecture (SCA) protocols
for direct host-to-storage communications. The DSSI cable can extend to 6
meters and has a peak bandwidth of 4 megabytes.
error
An incorrect response from a hardware module. An error can lead to a system
failure in non fault-tolerant systems. An error is a manifestation of a fault.
See fault.
Failover
The reconfiguration process that a fault-tolerant system undergoes to remain
operational after it experienced a failure or partial shutdown for planned
maintenance. See reconfiguration.
Failover Set Manager (FSM)
A VAXft System Services utility that ensures fault-tolerant access to I/O, for
example, the Ethernet. It permits users to manipulate the membership of
failover sets of redundant physical Ethernet adapters by adding or removing
them, or by changing their status.
Failure
Any system behavior that deviates from the system’s specifications. In regard
to the VAXft systems, failure often refers to a failed hardware component, such
as a CPU or memory module.
fault
A condition existing in a hardware or software module that can lead to module
failure. Typically, physical conditions such as worn-out modules, external or
environmental problems, design flaws, or manufacturing defects can cause
hardware faults. Software design flaws or implementation errors can cause
software faults.

Glossary–2

fault tolerant system
Fault tolerance is the degree to which a computer system maintains its
reliability and availability. A computer system that tolerates any single
point of failure and continues to provide virtually uninterrupted service to an
application is a fault-tolerant system.
FRU
Field Replaceable Unit. A unit designed to be replaced in the field by
appropriate personnel.
IZC
Inter-Zone Communication. A communication protocol that uses the serial
crosslink to establish communication between zones that are not operating in
lockstep.
lockstep
Simultaneous execution of the same instruction stream by the two CPU
modules in a VAXft system running in a synchronized, dual-zone configuration.
parallel crosslink
The portion of the crosslink used to communicate between system zones when
the system is running in lockstep operation.
PCM
Power and Cooling Monitor.
reconfiguration
The process of adding or removing devices from the failover set. See
synchronization.
Reliability
The likelihood that a system or system component will continue to function
over a given time period.
redundancy
Duplication of elements or components to provide alternative functional
channels in case of single component failures.
shadow set
Several physical disk drives, known as shadow set members, that are
associated with a software-created virtual unit for volume shadowing.

Glossary–3

synchronization
The process of synchronizing the CPU and memory modules of one zone
with those in the other zone of a dual-zone, fault-tolerant system. This step
occurs when a second zone is added to a running zone. When synchronization
is completed, the two zones of a fully configured VAXft system operate in
lockstep. See reconfiguration.
system disk
The disk that contains the VMS operating system.
system I/O controller module
VAXft I/O module. The I/O module contains Ethernet ports, DSSI bus
communications, and system console ports.
VAXft System Services
A VMS layered product required for using the VAXft 3000 system as a
fault-tolerant system.
VAXcluster system
A loosely coupled, highly integrated, distributed computing environment.
There are four types of VAXcluster system configurations, depending
on the medium used for interprocessor communications: CI-based,
local-area (Ethernet-based), DSSI-based (VAXft Model 612 system), and
mixed-interconnect VAXcluster systems.
volume shadowing
An implementation of disk shadowing in which duplication of data to more
than one volume is controlled through software that can reside on a central
server host in a local area VAXcluster system. It provides increased data
integrity and high availability to VAXft systems.
Y-connector
Hardware that joins two synchronous communication lines into into a single
output line.
zone
A section of a fully-configured VAXft system that contains a minimum of a CPU
module, memory module, I/O module, and associated devices. A fault-tolerant
system consists of two such zones with synchronized processor operations. If
one zone fails, processing continues uninterrupted through automatic failover
to the other zone.

Glossary–4