Compaq AlphaServer DS20 User manual

Compaq Computer Corporation
Maynard, Massachusetts
AlphaServer DS20 Ultra SCSI
Internal StorageWorks Shelf
Configuration Guide
Order Number: EK-H8253-IN. A01

First Printing, November 1998
The information in this publication is subject to change without notice.
COMPAQ COMPUTER CORPORATION SHALL NOT BE LIABLE FOR
TECHNICAL OR EDITORIAL ERRORS OR OMISSIONS CONTAINED
HEREIN, NOR FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES
RESULTING FROM THE FURNISHING, PERFORMANCE, OR USE OF
THIS MATERIAL. THIS INFORMATION IS PROVIDED “AS IS” AND
COMPAQ COMPUTER CORPORATION DISCLAIMS ANY WARRANTIES,
EXPRESS, IMPLIED OR STATUTORY AND EXPRESSLY DISCLAIMS THE
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR
PARTICULAR PURPOSE, GOOD TITLE AND AGAINST INFRINGEMENT.
This publication contains information protected by copyright. No part of this
publication may be photocopied or reproduced in any form without prior
written consent from Compaq Computer Corporation.
© 1998 Compaq Computer Corporation.
All rights reserved. Printed in the U.S.A.
The software described in this guide is furnished under a license agreement
or nondisclosure agreement. The software may be used or copied only in
accordance with the terms of the agreement.
Compaq, Compaq Insight Manager, registered United States Patent and
Trademark Office.
Microsoft and Windows NT are registered trademarks of Microsoft
Corporation.
Other product names mentioned herein may be trademarks and/or
registered trademarks of their respective companies.

AlphaServer DS20 Ultra SCSI Configuration Guide 1
Introduction
This document shows how to install and configure a second Ultra
SCSI bus repeater card on a Compaq AlphaServer DS20 system. The
following topics are covered:
•Kit Contents
•Configuration Diagrams
•Configuring the Ultra SCSI Bus
•Verifying the Configuration

2 AlphaServer DS20 Ultra SCSI Configuration Guide
Kit Contents
The Ultra SCSI Bus Splitter Kit (H8253-AA) contains the following
items for converting the single bus on the Compaq AlphaServer DS20
to a split bus:
Item Description Part Number
➊SCSI bus repeater card 30-48985-01
➋SCSI data cable (from SCSI controller to
repeater) 17-04890-01
➌SCSI data cable (from backplane to
repeater) 17-04022-03
➍Y power cable harness assembly 17-04700-01
➎SCSI active terminator assembly 17-04795-01
➏Cable ties (2) 90-09617-00
➐Documentation EK-H8253-IN
Figure 1 Kit Contents
PK0915
1
3
7
5
4
6
2

AlphaServer DS20 Ultra SCSI Configuration Guide 3
Single-Bus Configurations
The Compaq AlphaServer DS20 internal StorageWorks shelf is
configured for single-bus mode. Your system came with one of the
following StorageWorks configurations:
•A single-bus configuration with one multi-channel controller
(Figure 2).
•A single-bus configuration with two single-channel controllers
(Figure 3).
Figure 2 Single-Bus Configuration (One Multi-Channel Controller)
J10
J12
J11
J16
J13
J17
(Rear)
Repeater
W3
W2
W1
SE-A SE-B
Motherboard
2
3
4
5
6
1
0
StorageWorks Shelf
Bus B
PCI0 SLOT 7
PCI0 SLOT 8
PCI0 SLOT 9
PCI1 SLOT 8
PCI1 SLOT 9
ISA SLOT
PCI1 SLOT 7
Power
Supply
Bus A
PK0912
(Front)

4 AlphaServer DS20 Ultra SCSI Configuration Guide
Figure 3 Single-Bus Configuration (Two Single-Channel Controllers)
Power
Supply Motherboard
Bus B
StorageWorks Shelf
(Front)
Repeater
2
3
4
5
6
1
0
PCI0 SLOT 7
PCI0 SLOT 8
PCI0 SLOT 9
PCI1 SLOT 9
ISA SLOT
PCI1 SLOT 7
J10
J12
J11
J16
J13
J17
(Rear)
SE-A SE-B
PCI1 SLOT 8
Bus A
W3
W2
W1
PK0913

AlphaServer DS20 Ultra SCSI Configuration Guide 5
Split Bus Configuration
The H8253-AA kit allows you to convert the single bus to a split bus
(Figure 4). For this configuration, you must add a repeater card as
described in the following sections. Three SCSI controller channels
are required.
Figure 4 Split-Bus Configuration
W3
W2
W1
Power
Supply Motherboard
StorageWorks Shelf
Repeaters
SE-A SE-B
PCI0 SLOT 7
PCI0 SLOT 8
PCI0 SLOT 9
PCI1 SLOT 9
ISA SLOT
PCI1 SLOT 7
J10
J12
J11
J16
J13
J17
(Rear)
SE-A SE-B
PCI1 SLOT 8
Bus A
PK0914
Bus B
Bus C
(Front)
2
3
0
1
2
1
0
Bus B
Bus C

6 AlphaServer DS20 Ultra SCSI Configuration Guide
Converting to a Split Bus
Removing the System Covers
1. Shut down the operating system and power down the system
hardware.
2. Unplug the power cords.
3. Remove the covers of the enclosure to gain access to the
StorageWorks backplane. See Figure 5.
a. Unlock the front door and open the drive access area.
b. Pull the top cover latch down to unlock the cover.
c. Using the groove at the rear of the top cover, pull the cover
straight back about two inches, and lift up the cover.
d. Slide the left panel back, and then pull it up and away from
the unit. Repeat this step for the right panel.
Figure 5 Removing Covers
Top Cover
Release Latch
IP00205-97

AlphaServer DS20 Ultra SCSI Configuration Guide 7
Installing the Repeater Card
1. Snap the SCSI bus repeater card (30-48985-01) upright into the
standoffs on the side of the StorageWorks shelf. See 1.
2. Remove the connecting jumper cable from the StorageWorks
backplane. See 2.
3. Disconnect the power cable from the connector. See 3.
Figure 6 Installing the Repeater Card
3
2
1
PK0230

8 AlphaServer DS20 Ultra SCSI Configuration Guide
Connecting the Cabling
NOTE: Refer to Figure 7 to complete the following instructions.
1. Connect the center female connector of the Y power cable harness
assembly (17-04700-01). See 5.
2. Plug the other female connector of the Y-cable into the power
connector on the repeater card. See 6.
3. Plug the male end of the Y-cable into the power cable you
disconnected previously (page 7, step 3). See 7.
4. Connect one end of the short SCSI data cable (17-04022-03) to the
right SCSI connector on the repeater card. Connect the other end
to the connector on the StorageWorks backplane. See 8.
5. Connect one end of the long SCSI data cable (17-04890-01) to the
left SCSI connector on the repeater card. Dress the cable as on
the original card and connect the other end to a SCSI controller.
See 9.
6. Connect the terminator assembly. See 10.
7. Remove the W1 jumper and save it for future use, if desired. See
11.