Adaptec AHA-3980 User manual

AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: Front Cover
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
User’s Guide
AHA-3980/3980W/3985/3985W
PCI-to-SCSI MultiChannel RAID Adapters
With SCSI
Select

AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: Back Cover
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
Adaptec, Inc.
691 South Milpitas Boulevard
Milpitas, CA 95035
Copyright © 1996 Adaptec, Inc.
All rights reserved. Adaptec, the Adaptec
logo, and SCSISelect are trademarks of
Adaptec, Inc. which may be registered in
some jurisdictions.
Printed in Singapore
STOCK NO.: 510810-00, Rev. D RF 3/96

AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: i
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
R
▼ ▼ ▼ ▼ AHA-3980/3980W
/3985/3985W
PCI-to-SCSI MultiChannel RAID Adapters
with SCSI
Select
User’s Guide

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AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: ii
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
Copyright
Copyright © 1996 Adaptec, Inc. All rights reserved. No part of this publication may
be reproduced, stored in a retrieval system, or transmitted in any form or by any
means, electronic, mechanical, photocopying, recording or otherwise, without the
prior written consent of Adaptec, Inc., 691 South Milpitas Blvd., Milpitas, CA 95035.
Trademarks
Adaptec, the Adaptec logo, AHA, MultiChannel, and SCSISelect are trademarks of
Adaptec, Inc. which may be registered in some jurisdictions.
All other trademarks are owned by their respective owners.
Changes
The material in this document is for information only and is subject to change with-
out notice. While reasonable efforts have been made in the preparation of this docu-
ment to assure its accuracy, Adaptec, Inc. assumes no liability resulting from errors or
omissions in this document, or from the use of the information contained herein.
Adaptec reserves theright to make changes in the product design without reservation
and without notification to its users.
Adaptec Technical Support and Services
If you have questions about installing or using the host adapter, check this installation
guide first—you will find answers to most of your questions here. If you need further
assistance, please contact us. We offer the following support and information services:
■For technical support, for information about the Adaptec World Wide Web
(WWW) and File Transfer Protocol (FTP) Servers, the Adaptec forum on
CompuServe, the Adaptec USA Bulletin Board Service (BBS), and for access to the
Interactive Fax system, call 800-959-SCSI (7274) or 408-945-2550, 24 hours a day,
7 days a week. To speak with a product support representative, call 408-934-SCSI
(7274), M–F: 6:00 a.m. to 5:00 p.m., Pacific Time; after these hours, on weekends,
and on holidays, product support is also available for a fee at 800-416-8066.
– The Adaptec WWW and FTP Servers, and the Adaptec forum on CompuServe
provide product literature, answers to commonly asked questions, and infor-
mation on software upgrades and other topics. The WWW and FTP Servers are
available from the Internet 24 hours a day, 7 days a week, at http://
www.adaptec.com and ftp.adaptec.com. To access the Adaptec forum on
CompuServe 24 hours a day, 7 days a week, type GO ADAPTEC.
– The Adaptec BBS provides answers to commonly asked questions and infor-
mation on software upgrades and other topics. The BBS is available 24 hours a
day, 7 days a week, at 408-945-7727; 1200/2400/9600/14,400/28,800 baud, 8
data bits, 1 stop bit, no parity.
– The Adaptec Interactive Fax system provides product literature, answers to
commonly asked questions, and current information about Adaptec products
and services. The Adaptec Interactive Fax system is available 23 hours a day, 7
days a week. The Fax system is out of service 1 hour each day. You can call this
service directly at 408-957-7150.
■For sales information, call 800-959-SCSI (7274) or 408-945-2550, M–F: 6:00 a.m. to
5:00 p.m., Pacific Time.
■To order Adaptec software and SCSI cables, call 800-442-SCSI (7274) or
408-957-SCSI (7274), M–F: 6:00 a.m. to 5:00 p.m., Pacific Time.

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AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: iii
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
■To request additional documentation for Adaptec products, call 800-934-2766 or
510-732-3829, M–F: 6:00 a.m. to 5:00 p.m., Pacific Time.
FCC Compliance Statement
This equipment has been tested and found to comply with the limits for a Class B digital device,
pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection
against harmful interference in residential installations. This equipment generates, uses, and can
radiate radio frequency energy, and if not installed and used in accordance with the instructions,
may cause harmful interference to radio communications. However, there is no guarantee that
interference will not occur in a particular installation.
If this equipment does cause interference to radio or television equipment reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to correct the inter-
ference by one or more of the following measures:
• Reorient or relocate the receiving antenna
• Move the equipment away from the receiver
• Plug the equipment into an outlet on a circuit different from that to which the receiver is
powered
• If necessary, the user should consult the dealer or an experienced radio/television technician
for additional suggestions
CAUTION: Only equipment certified to comply with Class B (computer input/output devices,
terminals, printers, etc.) should be attached to this equipment, and must have shielded interface
cables.
Finally, any changes or modifications to the equipment by the user not expressly approved by the
grantee or manufacturer could void the user’s authority to operate such equipment.
Each host adapter is equipped with an FCC compliance label that shows only the FCC identifica-
tion number. The full text of the associated label follows:
This device complies with part 15 of the FCC rules. Operation is subject to the following two con-
ditions: (1) this device may not cause harmful interference and (2) this device must accept any
interference received, including interference that may cause undesired operation.
Canadian Compliance Statement
This Class B apparatus meets all requirements of the Canadian Interference-Causing Equipment
Regulations.
Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matérial
brouilleur du Canada.

AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: iv
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96

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Stock Number: 510810-00, Rev. D Page: v
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
▼ ▼ ▼ ▼ Contents
1 Getting Started
System Requirements 1-2
Using This Document 1-3
Conventions 1-4
Advisories 1-4
PART 1: Learning the Basics
2 Array Basics
Array Types 2-1
RAID 0 (Striped Disks) 2-1
RAID 1, RAID 1/0 (Mirrored Disks) 2-2
RAID 5 2-2
RAID 0 CVT and RAID 5 CVT 2-3
Disk Requirements 2-3
Number of Disks in an Array 2-3
Mixing Disks from Different Manufacturers or with
Different Capacities 2-4
Mixing Disks on Different RAID Adapter Channels 2-4
3 Understanding the Adaptec RAID Software
Adaptec Initial Array Configuration Utility 3-1
The Administrator Utility 3-2
The Adaptec CI/O Software 3-2
The Copy Drivers Utility 3-3
DOS and NetWare Device Drivers 3-3
4 Understanding the AHA-398x Adapter
Multiple Independent Channels 4-1
Standard SCSI and SCSI-2 Features 4-2

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Stock Number: 510810-00, Rev. D Page: vi
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
Synchronous and Asynchronous Data Transfers 4-2
The SCSISelect Configuration Utility 4-3
NetWare and DOS Support 4-3
Upgrading Your AHA-3980/3985 Adapter 4-3
Supported SCSI Devices 4-4
Devices Supported under NetWare 4-4
Devices Supported under MS-DOS 4-4
PART 2: Setting Up Arrays
5 Installing the AHA-398x and the SCSI Drives
AHA-398x Layout 5-2
Installing the AHA-398x in a PCI Slot 5-3
Connecting SCSI Devices 5-5
Choosing SCSI Cables 5-7
Connecting Internal SCSI Devices 5-7
Connecting External SCSI Devices 5-10
Terminating the SCSI Bus 5-12
Terminating Channels B and C 5-13
Terminating Channel A 5-14
Setting SCSI IDs and Preparing a Boot Device 5-15
Connecting the SCSI Bus Activity Light 5-16
Installing Multiple Adapters 5-17
Sharing SCSI Devices with a Second Computer 5-18
Completing AHA-398x Installation 5-20
6 Preparing a Boot Device and Installing Drivers
Getting Ready to Prepare a Boot Device 6-1
Creating an Array with the Initial Array Configuration
Utility 6-3
Formatting and Partitioning the Array or Drive 6-7
Copying Drivers 6-8
Installing NetWare on a New Server 6-9
NetWare 3.11 6-9
NetWare 3.12 6-9

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Contents
AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: vii
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
NetWare 4.xx 6-11
Other Initial Array Configuration Utility Options 6-14
Displaying Array Information 6-14
Deleting an Array 6-15
Replacing an Array Drive 6-16
Initializing an Array 6-16
PART 3: Managing Arrays
7 Understanding the Administrator Utility
Starting the Administrator Utility 7-2
Exiting the Administrator Utility 7-2
The Main and System Menus 7-3
Main Menu 7-3
System Menu 7-5
Selecting Menu Options 7-5
Grayed Menu Options 7-6
Getting Help 7-6
8 Monitoring Array Performance
Obtaining Array Information 8-1
Displaying Overview Information 8-2
Displaying Performance Statistics 8-3
Displaying Volume Information 8-4
Changing the Data Sampling Rate 8-4
Resetting the Temporary Statistics to Zero 8-4
Saving the Statistics in the Log File 8-5
Determining Who Receives Messages 8-5
Setting the Repeat Interval for Error Messages 8-7
The Log File 8-8
9 Managing Arrays
Verifying Arrays 9-1
Assigning a Priority 9-2
Verifying an Array Immediately 9-2

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Verifying an Array at a Scheduled Time 9-3
Canceling a Verification 9-3
Changing the Priority of a Verification in Progress 9-4
Testing Spare Disks 9-4
Reconstructing Data on a Replacement Disk 9-4
Reconstructing the Data Immediately 9-5
Reconstructing the Data at a Scheduled Time 9-6
Canceling Reconstruction 9-6
Changing the Priority for Reconstructing Data 9-6
Reactivating an Off-line Array 9-7
Scheduling Tasks 9-7
Scheduling a Task 9-7
Changing the Schedule 9-9
Deleting a Scheduled Task 9-9
Using the Hardware Functions 9-9
Identifying the Allocation of Host Adapter Drives 9-9
Locating a Drive 9-10
Pausing Host Adapter Activity When Replacing
Disks 9-11
10 Changing Array Configurations
Adding an Array 10-1
Modifying an Array 10-5
Changing the RAID Level 10-5
Selecting Different Disks for the Array 10-6
Adding a Spare Disk 10-6
Deleting a Spare Disk 10-7
Converting between RAID 0 CVT and RAID 5 CVT 10-7
Canceling a Conversion 10-9
Changing the Priority of a Conversion in Progress 10-9
Deleting Arrays and Deinstalling NLMs 10-10
Deleting an Array 10-10
Deinstalling NLMs 10-10
Installing the Array Utilities in the sys:system
Directory 10-11

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Contents
AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: ix
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
11 Initializing Arrays
Choosing the Initialization Method 11-1
Choosing the Data Block Size 11-2
Reinitializing an Array 11-2
12 Working from a Remote Workstation
Standard Adaptec CI/O Features 12-1
Adaptec CI/O Features When Working with the
Administrator Utility 12-2
Enabling a Remote Workstation to Receive Administrator
Utility Data 12-3
Remotely Accessing the Administrator Utility 12-4
PART 4: Advanced Hardware Topics
13 Configuring the Adapter with SCSI
Select
Default AHA-398x Settings 13-1
Basic Channel Settings 13-2
Host Adapter (Channel) SCSI ID 13-2
SCSI Parity Checking 13-3
Host Adapter SCSI Termination 13-3
Individual Settings for Each SCSI Device 13-3
Initiate Sync Negotiation 13-3
Maximum Sync Transfer Rate 13-4
Enable Disconnection 13-4
Send Start Unit Command 13-5
Include in BIOS Scan 13-5
Initiate Wide Negotiation (AHA-3980W/3985W
only) 13-5
SCSISelect Basics 13-6
Starting SCSISelect 13-6
Using SCSISelect Menus 13-7
Exiting SCSISelect 13-7
Changing the AHA-398x Settings 13-7
Listing SCSI IDs 13-11

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Formatting a SCSI Disk 13-11
Verifying a Disk 13-12
14 Using a CD-ROM Drive
Using a CD-ROM Drive under DOS 14-1
Using a CD-ROM Drive under NetWare 14-5
A Hardware Troubleshooting
Troubleshooting Checklist A-1
Startup Diagnostics A-2
BIOS Startup Messages A-3
aha3980.dsk Error Messages A-6
Disk Drive Configuration Problems A-7
Booting the Computer from a SCSI Drive A-8
Using a Standard Drive as C and a SCSI Drive as D A-8
Using SCSI Drives as C and D A-9
Computer Hangs, or Channel Cannot Always Find the
Drives A-9
Other Problems and Solutions A-10
B Software Error Messages
C Glossary of RAID Software
NetWare Drivers C-1
NetWare Loadable Modules C-2
Other Files C-4
❒

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1-1
1
▼ ▼ ▼ ▼
Getting Started
This User’s Guide explains how to install and use the Adaptec
AHA-398x family of MultiChannelPCI-to-SCSI RAID adapters,
which are designed to provide powerful disk array support in
NetWareservers that have a PCI (Peripheral Component Intercon-
nect) bus. Each AHA-398x adapter has either two or three SCSI chan-
nels; each channel has the equivalent functionality of a separate SCSI
bus. You can easily configure the adapter to boot the server from a
single SCSI disk drive or from an array.
There are four adapter models in the AHA-398x family:
■The AHA-3980 adapter has two Fast SCSI channels and sup-
ports up to 14 SCSI devices
■The AHA-3980W adapter has two Fast and Wide SCSI chan-
nels and supports up to 30 SCSI devices
■The AHA-3985 adapter has three Fast SCSI channels and sup-
ports up to 21 SCSI devices
■The AHA-3985W adapter has three Fast and Wide SCSI chan-
nels and supports up to 45 SCSI devices
AHA-398x adapters include software that helps you configure and
use arrays and other devices connected to the adapter. You use the
DOS-based Adaptec Initial Array Configuration Utility to prepare
an initial array and to make it bootable. You use the Copy Drivers
Utility to set up drivers for NetWare and for CD-ROM drives. You
use the console-based Administrator Utility, which runs under
NetWare, to add, delete, reconfigure, and manage arrays on an
ongoing basis.

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The CI/O software allows you to monitor and manage the network
from remote workstations.
System Requirements
The AHA-398x RAID adapter and software must be installed on a
NetWare server that has the following system resources:
Hardware/Firmware
■An 80486DX or Pentium computer that complies with PCI
Rev. 2.0
■A motherboard BIOS that supports PCI-to-PCI bridges, a
64-KByte BIOS, and multiple interrupts
If you are not sure which features the BIOS supports, contact
your vendor, or call Adaptec’s Interactive Fax Service for a list
of compatible motherboards. See Adaptec Technical Support and
Services on page ii.
■An available full-length PCI slot that supports bus mastering
and PCI Int B
■A 3.5-inch 1.44-MByte primary (boot) floppy disk drive
■A minimum of two SCSI disks for a RAID 0 or mirrored array;
a minimum of three SCSI disks for a RAID 0 CVT, RAID 5, or
RAID 5 CVT array (see Number of Disks in an Array on page 2-3)
■Two MBytes of hard disk space for the Adaptec RAID software
Software
■NetWare 386, version 3.11, 3.12, or 4.xx
■NetWare CLIB 3.12 or higher
■MS DOS 5.0 or above (MS-DOS 6.0 or above recommended)
■The Adaptec Initial Array Configuration Utility and AHA-3980/
3985 Drivers and RAID Utilities diskettes, which are included
with the AHA-398x
■To run CD-ROM drives under MS-DOS 5.0: The Microsoft
CD-ROM extension,
mscdex.exe , which is included with
MS-DOS 6.0 or above. (This file is also available on Microsoft’s
electronic bulletin board)

1-3
Getting Started
AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: 1-3
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
If you intend to use Adaptec CI/O, it must be installed on the
remote workstation from which you plan to monitor the arrays. See
the Adaptec CI/O documentation to learn the hardware and soft-
ware requirements for the remote workstation.
Using This Document
To use this document, first read Part 1 to learn the basics of arrays
and how they are supported by AHA-398x host adapters and the
supporting software. Part 1 also includes an overview of adapter
features and of the software included with the adapter. Pay particu-
lar attention to System Requirements on page 1-2.
Next, follow the instructions in Part 2 to physically install the
AHA-398x in your computer, attach the SCSI devices, prepare a boot
array or boot drive, and copy DOS and NetWare drivers to the
server.
Read Chapter 7 in Part 3 to learn the basics of the Administrator
Utility, which runs under NetWare. Then follow the instructions in
the rest of Part 3, as needed, to learn how to use this utility to moni-
tor array performance, manage your arrays, change array configura-
tions, add new arrays, and format arrays. Chapter 12 explains how
to use Adaptec CI/O to monitor your arrays from a remote
workstation.
Read Part 4 as needed to learn how to use the SCSISelect utility to
change AHA-398x configuration parameters and how to set up a
CD-ROM drive to install NetWare and other software.
Appendices A and B have troubleshooting information. Appendix C
describes the drivers and other RAID-related software included
with the AHA-398x.

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Current Date: 3/1/99 ECN Date: 3/19/96
Conventions
The following typographic conventions are used in this document:
bold
Used for key names (… press the Enter key …) and for options
you are directed to select (… select SCSI Disk Utilities …).
Helvetica
Used for screen messages (…Save changes?…) and for text
you must type exactly as shown.
Helvetica Italics
Used for program and file names when referenced in the text
(…
aspi8dos …).
Advisories
Advisories are quick notes that stress an important point or warn of
a potential hazard to the system or data. This document has three
kinds of advisories:
Note:
Text set off in this way presents reminders, tips, or sug-
gestions that may simplify the use of the AHA-398x.
Caution:
Failure to observe this type of advisory could result
in damage to your system, devices, or data.
WARNING:
Failure to observe this type of advisory could
result in personal injury.
Use caution when handling any electrical equipment. Advisories in
this document can only cover the procedures contained here, and
not all situations may have been addressed. Adaptec does not claim
to have included every condition or situation that might require a
Caution or Warning. You must refer to the documentation for your
computer and peripheral devices when you are installing equipment
or changing its configuration.
❒

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▼ ▼ ▼ ▼ Part 1
Learning the Basics

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AHA-3980/3980W/3985/3985W User’s Guide
Stock Number: 510810-00, Rev. D Page: 2-1
Print Spec Number: 493479-00
Current Date: 3/1/99 ECN Date: 3/19/96
2-1
2
▼ ▼ ▼ ▼
Array Basics
Adaptec’s RAID adapter and RAID software let you set up and man-
age disk arrays on NetWare servers. A disk array is a group of disks
that appears to the system as a single virtual disk. This is accom-
plished through software. RAID (Redundant Array of Inexpensive
Disks) refers to disk arrays in which part of the array storage capac-
ity may be used to store redundant information. The redundant
information lets you restore user data if a disk in the array fails.
A virtual disk is functionally identical to a physical disk. Depending
on the array type, however, the virtual disk has advantages in fault-
tolerance, cost, performance, or a combination of these. This chapter
explains the different array types and the disk requirements for each
type.
Array Types
Array types are defined by their RAID level, a number from 0
through 6 (a higher RAID level does not indicate a higher level of
performance or fault-tolerance). Adaptec RAID software lets you
create the types of arrays that have proven to be the most useful for
NetWare RAID applications: RAID 0, 1, 1/0, and 5.
RAID 0 (Striped Disks)
In a RAID 0 array, data is distributed, or striped, across the disks in
the array. The array appears to the server as one large disk with a
capacity approximately equal to the combined capacity of the physi-
cal disks. Because multiple reads and writes can be handled in paral-
lel, the input/output performance of the array is much better than
that of a single physical disk.

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RAID 0 arrays do not store redundant data, so they are not true
RAID applications. If one disk fails, the entire array fails and all array
data is lost. The fault-tolerance of a RAID 0 array, therefore, is less
than that of any single disk in the array. The term RAID 0 is widely
used for these arrays, however, because they are conceptually similar
to true RAID applications.
RAID 1, RAID 1/0 (Mirrored Disks)
In RAID 1 and RAID 1/0 arrays (commonly called mirrored arrays)
disks are paired, with both disks in a pair containing the same data.
When data is written to a mirrored array, it is written twice—once to
each disk in the pair. A RAID 1 array has only one set of paired disks.
A RAID 1/0 array has multiple pairs, across which data is striped.
The read performance of RAID 1 arrays can be much better than that
of a single disk, while the write performance is slightly worse. In
RAID 1/0 arrays, both read performance and write performance are
better than those of a single disk.
A mirrored array is also highly reliable, because both disks in a pair
must fail for the array to fail. In an array with five pairs of mirrored
disks, for example, the array can maintain its integrity if even five
disks fail—as long as each pair is left with one good disk. The main
disadvantage of a mirrored array is its cost. Because all disks must
have a twin, you must use twice the number of disks that actually
contribute to the array capacity. In an eight-disk array, for example,
you have only four disks of usable capacity.
RAID 5
RAID 5 arrays contain redundant information in the form of parity
data, which is calculated block by block for all user data. The parity
information is distributed across the disks in the array, as in RAID 0
arrays, and occupies the equivalent capacity of about one disk. Data
is interspersed with the parity information. If one disk in the array
fails, the data on the failed disk can be reconstructed from the parity
data and user data on the remaining disks. Two disks must fail
before the entire array fails.
The read performance of a RAID 5 array is excellent—comparable to
that of a RAID 0 array. Write performance is lower than that of a
RAID 0 array, because write operations involve calculating and writ-
ing new parity data as well as writing the new user data.