Integrated Cached Disk Array - Dell...EMC Corporation 171 South Street, Hopkinton, MA...

Integrated Cached Disk ArrayIntegrated Cached Disk Array

SYMMETRIXModel 3330/5330

Product ManualP/N 300-857-001

REV A

EMC Corporation 171 South Street, Hopkinton, MA 01748-9103Corporate Headquarters: (508) 435-1000, (800) 424-EMC2

Fax: (508) 435-5374, Service: (800) SVC-4EMC

Copyright © 1998 EMC Corporation. All rights reserved.Printed November 1998First Edition

No part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written consent of EMC Corporation.

The information contained in this document is subject to change without notice. EMC Corporation assumes no responsibility for any errors that may appear.

All computer software programs, including but not limited to microcode, described in this document are furnished under a license, and may be used or copied only in accordance with the terms of such license. EMC either owns or has the right to license the computer software programs described in this document. EMC Corporation retains all rights, title and interest in the computer software programs.

EMC Corporation makes no warranties, express or implied, by operation of law or otherwise, relating to this document, the products or the computer software programs described herein. EMC CORPORATION DISCLAIMS ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. In no event will EMC Corporation be liable for (a) incidental, indirect, special or consequential damages or (b) any damages whatsoever resulting from the loss of use, data or profits, arising out of this document, even if advised of the possibility of such damages.

Regulatory Agency Certification

Symmetrix has been extensively tested and certified to meet UL1950, CSA 950, IEC 950/EN60 950; Safety of Information Technology Equipment Including Electrical Business Equipment, FCC Rules, Part 15 Subpart B, CISPR 22 Class A/EN 55022, IEC 801-2/EN 55024-2, IEC 801-3/EN 55024-3, IEC 801-4/EN 55024-4.

This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations, ICES-003.

Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le matériel brouiller du Canada, ICES-003.

Trademark Information

Compaq is a registered trademark and ProLiant is a trademark of Compaq Computer Corporation.Digital, DEC, and AlphaServer are trademarks of Digital Equipment Corporation.HP and Openview are registered trademarks of Hewlett-Packard Company.

AIX, AS/400, DFSMS/MVS, ES/9000, IBM, MVS, OS/2, OS/400, PS/2, RISC System/6000, S/390, System/390, and VM/ESA are registered trademarks and 3090, 9337, ACP, DFSMS, ECKD, ESA, ESA/390, ESCON XDF, HACMP, MVS/DFP, MVS/ESA, MVS/SP, MVS/XA, MVT/VSE, RACF, RMF, RS/6000, S/370, SP2, System/370, TPF, VM/HPO, VM/SP, VM/VSE, VM/XA, VSE,VSE/ESA, XDF, InfoExplorer, InfoTrainer, ESCON, and PowerPC are trademarks of International Business Machines Corporation.Pentium is a registered trademark of Intel Corporation.Microsoft and Windows NT are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries.Russellstoll is a registered trademark of Midland-Ross Corporation.NCR is a registered trademark of NCR Corporation.Novell and NetWare are registered trademarks of Novell, Inc.Oracle is a registered trademark of Oracle Corporation.Network Computing System is a trademark of Apollo Computer, Inc.Motorola is a registered trademark of Motorola, Inc.OpenView is a registered trademark of Hewlett-Packard Company.DataCenter, OSx, Pyramid, and the Pyramid logo are registered trademarks and DC and Nile are trademarks of Pyramid Technology Corporation.Seagate is a registered trademark and Elite is a trademark of Seagate Technology, Inc.Siemens is a registered trademark and TransView is a trademark of Siemens Nixdorf Information Systems.Sequent, DYNIX, and DYNIX/ptx are registered trademarks of Sequent Computer Systems, Inc.

Silicon Graphics and CHALLENGE are registered trademarks and IRIX and XFS are trademarks of Silicon Graphics, Inc.SunOS and Sun Microsystems are trademarks of Sun Microsystems, Inc.SPARC, SPARCcenter, and SPARCserver are trademarks of SPARC International, Inc., licensed exclusively to Sun Microsystems. SYBASE is a registered trademark of Sybase, Inc.

UNISYS is a registered trademark of Unisys Corporation.UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company, Ltd.

FDR and Innovation are registered trademarks and FDRSOS is a trademark of Innovation Data Processing.Informix is a registered trademark of Informix Software, Inc.Legato and NetWorker are registered trademarks of Legato Systems, Inc.

EMC2 (the EMC logo), EMC, ICDA (Integrated Cached Disk Array), MOSAIC:2000, and Symmetrix are registered trademarks and EMC Enterprise Storage, EMC Storage Logic, CopyPoint, DataReach, EDM, EOS, Extended-Online, FarPoint, InfoMover, PowerPath, SDMS, SRDF, TimeFinder, The EMC Effect, and The Enterprise Storage Company are trademarks of EMC Corporation.

All other trademarks used herein are the property of their respective owners.

Contents

Preface .................................................................................xv

Warnings and Cautions................................................... xxvii

Chapter 1 Introducing Symmetrix .................................1

1.1 Overview ..................................................................... 2Enterprise Storage Architecture: MOSAIC: 2000

and ISA ................................................................. 3Symmetrix 3330/5330 Capacities ......................... 5

1.2 Channel Connectivity and Host Integration .......... 8Symmetrix 3330-xx Channel Connectivity.......... 8Symmetrix 5330-xx Channel Connectivity.......... 8Symmetrix Channel Configurations .................... 9Parallel and Serial Channel Interfaces ................. 9Mainframe Operating Systems Supported ....... 10Ultra SCSI Channel Interfaces............................. 13Fibre Channel Interfaces ...................................... 14Supported Cluster Hosts ..................................... 15

1.3 Performance Features .............................................. 161.4 Availability Features ................................................ 171.5 Serviceability Features ............................................. 181.6 Supported Mainframe Features ............................. 19

Multi-Subsystem Imaging ................................... 201.7 Hardware Options.................................................... 221.8 Software Options ...................................................... 23

Information Protection......................................... 23Information Sharing ............................................. 29Information Management.................................... 32EMC Enterprise Backup Solutions ..................... 40

v

Chapter 2 Symmetrix 5330/3330 Hardware................45

2.1 Major Components................................................... 46Component Overview.......................................... 47

Symmetrix 5330/3330 Block Diagram ........... 482.2 Operator Panel .......................................................... 49

Disk Director Display........................................... 49Channel Director Display .................................... 50

2.3 Disk Devices.............................................................. 51Symmetrix 3330 Disk Device Emulations ......... 52Symmetrix 5330 Disk Device Emulations ......... 52Open Systems SCSI Disk Emulation.................. 52IBM DASD Disk Emulation................................. 54

2.4 Directors and Cache ................................................. 58Channel Director Connectivity ........................... 58Channel Director Descriptions............................ 59Disk Director.......................................................... 63Cache ...................................................................... 64

2.5 Channel Attachments .............................................. 65Parallel Channel Interface Connections ............ 65Serial Channel Interface Connections................ 67Parallel and Serial Channel Extenders............... 68Fast-Wide and Ultra-Fast-Wide SCSI Channel

Attachments ....................................................... 70Fibre Channel Attachments................................. 71

Chapter 3 Symmetrix Input/Output Operations .........73

3.1 ICDA Operation ....................................................... 74Symmetrix Cache Management.......................... 75Symmetrix I/O Performance Enhancements ... 78

3.2 Elements of a Symmetrix I/O Operation.............. 79I/O Response Time - Mainframe Environment 79I/O Response Time - Open Systems

Environment ...................................................... 80Symmetrix I/O Operations ................................. 81Destaging Operation ............................................ 82Read Operations.................................................... 83Write Operations................................................... 85

3.3 Dynamic Path Reconnection (Mainframe Systems) ............................................... 87

vi Contents

Chapter 4 Getting the Best Performance....................89

4.1 Performance Features .............................................. 90Cache ...................................................................... 90Fast Write Capabilities ......................................... 90Multiple Channel Directors................................. 91Parallel Processing ................................................ 91Dynamic Mirror Service Policy........................... 92RPS Miss Elimination ........................................... 92Channel Speeds..................................................... 92PermaCache Option ............................................. 93

4.2 Open Systems Hyper-Volumes .............................. 95Split-Volume Capability....................................... 96Logical Volume Mapping .................................... 98Meta Volume Addressing .................................... 99Meta Volume Data Striping................................. 99

4.3 Mainframe System Hyper-Volumes .................... 101Split-Volume Capability..................................... 102Extended Cylinder Addressing Option........... 102Determining Cylinders for Hyper-Volume

Data ................................................................... 1034.4 Optimizing Performance for Open Systems

Devices ..................................................................... 1074.5 Performance Guidelines for Mainframe

Devices ..................................................................... 109Identifying Requirements .................................. 109Choosing Storage Devices ................................. 110

4.6 Monitoring Symmetrix Performance in a Mainframe Environment ....................................... 112

Setting Performance Objectives ........................ 112Using RMF ........................................................... 112Using VM/Monitor and VMPPF...................... 113Using Cache RMF Reporter............................... 113

4.7 Multi-Port Volume Access for Open Systems Environments.......................................................... 115

Chapter 5 Managing Critical Data............................117

5.1 Symmetrix Data Management Overview ........... 118

Contents vii

Symmetrix Reliability and Availability Features............................................................. 118

Symmetrix Data Integrity Protection Features119Data Protection Options..................................... 119

5.2 Reliability and Availability Features ................... 122Reliable Components ......................................... 122Redundant Power Subsystem........................... 122System Battery Backup ...................................... 123Dual-Initiator Feature ........................................ 124Non-disruptive Component Replacement...... 128Microcode Upgrades and Loads....................... 129

5.3 Data Integrity Protection ....................................... 131Error Checking, Correction, and Data

Integrity Protection ......................................... 131Disk Error Correction and Error Verification.. 132Cache Error Correction and Error Verification133

5.4 Data Protection Guidelines ................................... 1345.5 Mirroring ................................................................ 135

Write Operations with Mirroring ..................... 135Read Operations with Mirroring...................... 136Error Recovery with Mirroring......................... 136Mirroring Advantages ....................................... 137

5.6 Symmetrix RAID-S................................................. 138RAID-S Technology ............................................ 138Data Protection Flexibility ................................. 139RAID-S Components.......................................... 139RAID-S Modes of Operation ............................. 143Writing Data in a RAID-S Group...................... 145Reading Data in a RAID-S Group .................... 147Data Recovery with RAID-S.............................. 148RAID-S Advantages ........................................... 152

5.7 Symmetrix Remote Data Facility ........................ 1545.8 Dynamic Sparing ................................................... 1555.9 Dynamic Sparing as Additional Protection........ 158

Dynamic Sparing with Locally Mirrored Pairs.................................................. 158

Dynamic Sparing with RAID-S Volumes ........ 159Dynamic Sparing with Remotely Mirrored Pairs

(SRDF)............................................................... 162

viii Contents

Chapter 6 Error Reporting and Recovery..................163

6.1 Types of Errors ........................................................ 164Temporary and Permanent Errors.................... 164Recoverability by Error Type ............................ 165

6.2 Error Reporting....................................................... 168Event Messages ................................................... 170Operator Messages ............................................. 171

6.3 EREP Reports .......................................................... 173EREP Error Records............................................ 173

6.4 Error Handling........................................................ 175Detecting the Error ............................................. 175Determining Error Source.................................. 176

Appendixes........................................................................177

A Sense Byte Information .............................179

B Symmetrix 3330/5330 Specifications.......185

C Power Sequences......................................201

D Planning and Installation ..........................209

Glossary .............................................................................235

Index...................................................................................249

Sales and Service Locations ............................................259

Contents ix

x Contents

Figures

1 Symmetrix 3330/5330 ICDA ..................................................................... 22 MOSAIC:2000 Architecture....................................................................... 33 Intelligent Storage Architecture (ISA) ..................................................... 44 Symmetrix 5330/3330 (Interior View) ................................................... 465 Symmetrix 5330/3330 Block Diagram ................................................... 486 Operator Panel .......................................................................................... 497 Track Format for 3390 and 3380 DASD ................................................. 558 Parallel Channel Attachment .................................................................. 669 Parallel Channel Attachment to ESCON Channels ............................. 66

10 ESCON Channel Attachment.................................................................. 6811 Possible Channel Attachments ............................................................... 6912 Fast-Wide and Ultra SCSI Attachments ................................................ 7113 Host Cache Use ......................................................................................... 7414 Symmetrix Cache Management and Data Flow................................... 7515 LRU and Age Link Chain Data Flow..................................................... 7716 I/O Response Time (Mainframe Environment)................................... 7917 I/O Response Time (Open Systems Environment) ............................. 8018 Types of Symmetrix I/O Operations ..................................................... 8119 Destaging Operation ................................................................................ 8220 Read Operations........................................................................................ 8321 Read Hit ..................................................................................................... 8422 Read Miss ................................................................................................... 8423 Write Operations....................................................................................... 8524 Fast Write ................................................................................................... 8625 Delayed Fast Write ................................................................................... 8626 3:1 Logical Volume Mapping.................................................................. 9827 2:1 Logical Volume Mapping.................................................................. 9828 Data Access Activity............................................................................... 10929 Storage Hierarchy ................................................................................... 11030 Symmetrix 3330/5330 Dual-Initiator Example................................... 12531 Data Record Format for Conventional DASD .................................... 13132 Symmetrix Data Record Format ........................................................... 13233 RAID-S Group Definitions .................................................................... 14034 RAID-S Group Without Hyper-Volumes............................................ 141

Figures xi

35 RAID-S Group With Hyper-Volumes.................................................. 14236 Parity Protection Logic........................................................................... 14437 RAID-S Write Operations...................................................................... 14638 Writing to a RAID-S Group in Reduced Mode .................................. 14939 Reading from a RAID-S Group in Reduced Mode ............................ 15040 Regenerating Data or Parity After Disk Replacement....................... 15241 Dynamic Sparing Process ...................................................................... 15542 Dynamic Sparing with Locally Mirrored Pairs Dynamic Sparing

with RAID-S Volumes .................................................................... 15943 Dynamic Sparing with RAID-S Volumes............................................ 16144 MVS IEA480E Service Alert Error Message Format

(AC power failure) .......................................................................... 17145 MVS IEA480E Service Alert Error Message Format

(mirror-1 volume in “not ready” state) ........................................ 17146 MVS IEA480E Service Alert Error Message Forma

(mirror-2 resynchronization) ......................................................... 17247 MVS IEA480E Service Alert Error Message Format

(mirror-1 resynchronization) ......................................................... 17248 Typical Console Error Message ............................................................ 18149 Floor Tile Cutout..................................................................................... 21450 Symmetrix 3330/5330 Channel/Memory Configurations ............... 21651 Fast-Wide SCSI or Ultra SCSI Director Channel Designations........ 233

xii Figures

Tables

1 Symmetrix 3330-18 and 5330-18 SRDF Capacities ................................ 52 Symmetrix 3330-18 and 5330-18 Mirrored (RAID-1) Capacities.......... 63 Symmetrix 3330-18 and 5330-18 RAID-S Capacities.............................. 64 Symmetrix 3330-9 and 5330-9 SRDF Capacities .................................... 65 Symmetrix 3330-9 and 5330-9 Mirrored (RAID-1) Capacities.............. 66 Symmetrix 3330-9 and 5330-9 RAID-S Capacities.................................. 77 IBM Controller / DASD Compatibility ................................................. 108 EMC Supported Fast-Wide SCSI Single Hosts .................................... 129 EMC Supported Ultra Fast-Wide SCSI Single Hosts .......................... 13

10 EMC Supported Fibre Channel Single Hosts ...................................... 1411 EMC Supported Cluster Hosts ............................................................... 1512 IBM DASD Emulation Characteristics................................................... 5413 Channel Director Configurations ........................................................... 6014 Cylinders per Logical Volume for Split Physical Devices .............. 9715 Meta Volume Stripe Sizes........................................................................ 9916 Available Cylinders for 18 GB and 9 GB Emulated Disk Devices... 10417 Device Emulations and ........................................................................ 10418 Data Protection Options ........................................................................ 13419 Environmental Alert Messages ............................................................ 16920 Event Messages ...................................................................................... 17021 Error Handling Steps.............................................................................. 17522 Unit Status Bits ........................................................................................ 18223 Channel Status Bits ............................................................................... 18324 Symmetrix 3330-18/5330-18 SRDF Capacities .................................. 18725 Symmetrix 3330-18/5330 18 Mirrored (RAID-1) Capacities ............ 18726 Symmetrix 3330-18/5330-18 RAID-S Capacities................................ 18827 Symmetrix 3330-9/5330-9 SRDF Capacities ....................................... 18828 Symmetrix 3330-9/5330-9 Mirrored (RAID-1) Capacities ................ 18929 Symmetrix 3330-9/5330-9 RAID-S Capacities ................................... 18930 Pre-Installation Responsibility Summary ........................................... 21031 Parallel Channel Path Assignments ................................................... 21732 Serial Channel Path Assignments, 2-port Serial Channel Director 21833 Serial Channel Path Assignments, 4-port Serial Channel Director 219

Tables xiii

34 Volume Addresses and Cylinders........................................................ 22035 Volume Work Sheet .............................................................................. 22336 Symmetrix Checklist for UNIX or PC Server Hosts .......................... 22537 Symmetrix 3330 Checklist for AS/400 Hosts...................................... 22638 UNIX or PC Server Host Checklist ...................................................... 22739 AS/400 Host Checklist .......................................................................... 22940 SCSI Cable Worksheet ........................................................................... 231

xiv Tables

Preface

As part of its effort to continuously improve and enhance the performance and capabilities of the Symmetrix product line, EMC from time to time releases new revisions of Symmetrix hardware and microcode. Therefore, some functions described in this manual may not be supported by all revision of Symmetrix microcode or hardware presently in use. If your Symmetrix unit does not offer a function described in this manual, please contact your EMC representative for a hardware upgrade or microcode update.

This manual is part of the documentation set for the following Symmetrix 3330/5330 products:

• Symmetrix 3330-18 systems have 18 GB disk devices and connect to open systems hosts

• Symmetrix 3330-9 systems have 9 GB disk devices and connect to open systems hosts

• Symmetrix 5330-18 systems have 18 GB disk devices and connect to mainframe systems hosts

• Symmetrix 5330-9 systems have 9 GB disk devices and connect to mainframe systems hosts

When the optional Symmetrix Enterprise Storage software enabler option is added, each of the above Symmetrix models can access both mainframe and open systems disk devices.

Symmetrix is a very reliable high performance Integrated Cached Disk Array (ICDA) designed for online data storage. Symmetrix houses both

xv

xvi Preface

controller and data storage capabilities in a single cabinet. This manual describes the Symmetrix 3330/5330 features and operations.

▼ WARNING: The Symmetrix 33xx/53xx contains no user-serviceable parts, so it should not be moved or opened for any reason by untrained persons. If the Symmetrix is in need of relocation or repair, only qualified personnel familiar with safety procedures for electrical equipment and the Symmetrix should access components inside the unit or move the unit.

This manual is intended for the storage administrator, system programmer, or operator who is involved in acquiring, managing, or operating the Symmetrix subsystem.

Here is an overview of where information is located in this manual.

Chapter 1, “Introducing Symmetrix,” provides an overview of the Symmetrix 3330/5330, highlighting its performance and reliability features, and describes hardware and software options for the unit.

Chapter 2, “Symmetrix 3330/5330 Hardware,” introduces the hardware components of the Symmetrix 3330/5330. It describes its main components, the function of the operator panel, and the types of host channels and devices to which Symmetrix can attach.

Chapter 3, “Symmetrix Input/Output Operations,” discusses integrated cached disk arrays, I/O operation, and cache management.

Chapter 4, “Getting the Best Performance,” describes the Symmetrix 3330/5330 performance features, how they will affect overall performance, and how to use these features to get the best performance from Symmetrix.

Chapter 5, “Managing Critical Data,” discusses the Symmetrix features that affect data availability and reliability.

Chapter 6, “Error Reporting and Recovery,” describes the types of errors possible with Symmetrix, error handling techniques, and provides an error recovery summary.

Appendix A, “Sense Byte Information,” describes the sense byte data Symmetrix presents to the host when it detects an error condition.

Appendix B, “Symmetrix 3330/5330 Specifications,” lists the operating, physical, and environmental, and electrical specifications for the Symmetrix 3330/5330.

Appendix C, “Power Sequences,” provides step-by-step instructions for powering the Symmetrix 3330/5330 on and off.

Appendix D, “Planning and Installation,” contains several work sheets for product installation.

The Glossary defines terms used in this manual.

RelatedDocumentation

Other Symmetrix publications include:

• Symmetrix Open Systems Environment Product Guide, Volumes I & II, P/N 200-999-563, EMC Corporation

• Symmetrix Enterprise Storage Platform Product Guide, P/N 200-999-556, EMC Corporation

• Symmetrix High Availability Product Guide, P/N 200-999-566, EMC Corporation

Preface xvii

• Symmetrix Manager Workload Analyzer Product Guide, P/N 200-999-631, EMC Corporation

• Smmetrix Manager SymmConsole for Windows with Agents for Windows NT, UNIX, and MVS Product Guide, P/N 200-999-640, EMC Corporation

• Symmetrix Manager Base Component for UNIX Product Guide, P/N 200-999-568, EMC Corporation

• Symmetrix Manager Base Component for Windows NT Product Guide, P/N 200-999-590, EMC Corporation

• Symmetrix Manager SRDF Component for UNIX Product Guide, P/N 200-999-565, EMC Corporation

• Symmetrix Manager SRDF Component for Windows NT Product Guide, P/N 200-999-589, EMC Corporation

• Symmetrix Manager SDDR Component for UNIX Product Guide, P/N 200-999-595, EMC Corporation

• Symmetrix Manager SDDR Component for Windows NT Product Guide, P/N 200-999-594, EMC Corporation

• Symmetrix Manager TimeFinder Component for Windows NT Product Guide, P/N 200-999-591, EMC Corporation

• Symmetrix Manager TimeFinder Component for UNIX Product Guide, P/N 200-999-592, EMC Corporation

• EMC TimeFinder Command Line Interface for UNIX Product Guide, P/N 200-999-593, EMC Corporation

xviii Preface

• EMC TimeFinder Command Line Interface for Windows NT Product Guide, P/N 200-999-600, EMC Corporation

• EMC TimeFinder MVS Batch Utility Product Guide, P/N 200-999-574, EMC Corporation

• EMC TimeFinder MSP Batch Utility Product Guide, P/N 200-999-643, EMC Corporation

• EMC Solutions Enabler SYMCLI Base Component Product Guide, P/N 200-999-624, EMC Corporation

• EMC Solutions Enabler Installation Procedures Product Guide, P/N 200-999-635, EMC Corporation

• EMC Solutions Enabler SYMCLI SRDF Component Product Guide, P/N 200-999-625, EMC Corporation

• EMC Solutions Enabler SYMCLI TimeFinder Component Product Guide, P/N 200-999-634, EMC Corporation.

• Symmetrix Remote Data Facility Product Guide, P/N 200-999-554, EMC Corporation

• Symmetrix SRDF Host Component Product Guide, P/N 200-999-561, EMC Corporation

• Symmetrix Data Migration Facility Product Guide, P/N 200-999-559, EMC Corporation

• EMC InfoMover Product Guide, P/N 200-999-619, EMC Corporation

• EMC CopyPoint for AS/400 Product Guide, P/N 300-999-004

• EMC PowerPath Product Guide, P/N 200-999-598, EMC Corporation

Preface xix

• EMC Enterprise Backup Solutions Product Guide, P/N 200-999-618, EMC Corporation

• FDRSOS Installation and User’s Guide, Innovation Data Processing (IDP)

• DataReach User Guide, P/N DRAPMU1073197, BMC Software

• Legato NetWorker for EMC Symmetrix Installation and Administration Guide, Solaris Version for Oracle 7.3, Legato Systems, Inc.

For information about EMC Data Manager, refer to the following publications:

• EDM Software Reference, P/N 200-113-569, EMC Corporation

• EDM Software Release Notes, P/N 201-113-555, EMC Corporation

• EDM Storage Devices, P/N 201-113-556, EMC Corporation

• EDM Symmetrix Connect User Guide, P/N 200-113-571, EMC Corporation

• EDM Symmetrix Connect Quick Reference Card, P/N 200-113-576, EMC Corporation

• EDM Client Supplement CD Release Notes, P/N 200-122-556, EMC Corporation

• EDM NetWare Backup Client Guide, P/N 200-114-552, EMC Corporation

• EDM NetWare Backup Client Release Notes, P/N 200-114-553, EMC Corporation

• EDM OpenVMS Backup Client Guide, P/N 200-122-554, EMC Corporation

• EDM OpenVMS Backup Client Release Notes, P/N 200-122-555, EMC Corporation

xx Preface

• EDM OS/2 Backup Client Guide, P/N 200-118-552, EMC Corporation

• EDM OS/2 Backup Client Release Notes, P/N 200-118-553, EMC Corporation

• EDM Windows NT Backup Client Guide, P/N 200-119-552, EMC Corporation

• EDM Windows NT Backup Client Release Notes, P/N 200-119-553, EMC Corporation

• EDM Windows NT SQL Server Backup, P/N 200-119-554, EMC Corporation

• Oracle Online Database Backup (OLDB) for EDM Release Notes, P/N 200-115-555, EMC Corporation

• EDM Oracle Online Backup Guide, P/N 200-115-550, EMC Corporation

• EDM Oracle Online Backup Release Notes, P/N 200-115-553, EMC Corporation

For information about HP OpenView OmniBack II, refer to the following publications:

• HP OpenView OmniBack II Administrator’s Guide, P/N B1957-90036, Hewlett-Packard Company

• HP OpenView OmniBack II Installation Guide, P/N B1957-90034, Hewlett-Packard Company

• HP OpenView OmniBack II Integration Guide, P/N B1957-90027, Hewlett-Packard Company

• HP OpenView OmniBack II Advanced Backup Manager, P/N B1957-90025, Hewlett-Packard Company

• HP OpenView OmniBack II Symmetrix Integration Training, Hewlett-Packard Company

Preface xxi

• HP OpenView OmniBack II and EMC Symmetrix Whitepaper, Hewlett-Packard Company

The following IBM documents provide additional reference information:

• Introducing ESCON, P/N GA23-0383, International Business Machines Corporation

• Using ESCON Directors, P/N GA23-0354, International Business Machines Corporation

• Introducing ESCON Directors, P/N GA23-0363, International Business Machines Corporation

• Introducing the ESCON Manager, P/N GC23-0422,International Business Machines Corporation

• Planning for the ESCON Manager, P/N GC23-0423, International Business Machines Corporation

• Using the ESCON Manager, P/N GC23-0425, International Business Machines Corporation

• Diagnosing the ESCON Manager, P/N GC23-0429,International Business Machines Corporation

• ESCON Manager Reference Summary, P/N SX23-0412, International Business Machines Corporation

• IBM ES/9000 PR/SM Planning Guide, P/N GA22-7123, International Business Machines Corporation

• Planning Dynamic I/O Configuration, P/N GC28-1674, International Business Machines Corporation

• Support for the ESCON Multiple Image Facility, P/N GC28-1172, International Business Machines Corporation

xxii Preface

• ESCON: Planning for Migration, P/N GC66-3181, International Business Machines Corporation

• Automating the ESCON Manager through the API, P/N SC23-0427, International Business Machines Corporation

• IOCP User Guide, P/N SC38-0097, International Business Machines Corporation

• IBM 3990 Storage Control Reference, P/N GA32-0993, International Business Machines Corporation

• IBM 3390 Direct Access Storage Introduction, P/N GC26-4573, International Business Machines Corporation

• Using the IBM 3390 Direct Access Storage in an MVS Environment, P/N GC26-4574, International Business Machines Corporation

• Using the IBM 3390 Direct Access Storage in a VM Environment, P/N GC26-4575, International Business Machines Corporation

• Using the IBM 3390 Direct Access Storage in a VSE Environment, P/N GC26-4576, International Business Machines Corporation

• IBM 3380 Direct Access Storage Introduction, P/N GC26-4491, International Business Machines Corporation

• Using the IBM 3380 Direct Access Storage in an MVS Environment, P/N GC26-4492, International Business Machines Corporation

• Using the IBM 3380 Direct Access Storage in a VM Environment, GC26-4493, International Business Machines Corporation

Preface xxiii

• Using the IBM 3380 Direct Access Storage in a VSE Environment, GC26-4494, International Business Machines Corporation

• MVS/XA MVS Configuration Program Guide and Reference, P/N GC28-1335, International Business Machines Corporation

• MVS/Extended Architecture Planning: Recovery and Reconfiguration, P/N GC28-1160, International Business Machines Corporation

• VSE/AF System Management Guide, P/N SC33-6191, International Business Machines Corporation

• VSE/SP System Administration, P/N SC33-6306, International Business Machines Corporation

• VSE/Advanced Functions System Control Statements, P/N SC33-6198, International Business Machines Corporation

• IBM System/370 Principles of Operation, P/N GA22-7000, International Business Machines Corporation

• IBM System/370-XA Principles of Operation, P/N GA22-7085, International Business Machines Corporation

• IOCP User’s Guide and Reference, P/N GC28-1027, International Business Machines Corporation

• ICKDSF User’s Guide and Reference, P/N GC35-0033, International Business Machines Corporation

• IBM Environmental Record Editing and Printing Program (EREP) User’s Guide and Reference, P/N GC28-1378, International Business Machines Corporation

xxiv Preface

• RMF Reference and User’s Guide, P/N LY28-1107, International Business Machines Corporation

• Cache RMF Reporter Program Description/Operations Manual, P/N SH20-6295-4, International Business Machines Corporation

Request copies of these IBM manuals from your local IBM office.

Conventions Usedin this Manual

EMC uses the following conventions for notes, cautions, and warnings.

A note presents information that is important, but not hazard-related.

▼ CAUTION: A caution contains information essential to avoid a hazard that will or can cause minor personal or property damage if you ignore the warning.

▼ WARNING: A warning contains information essential to avoid a hazard that can cause severe personal injury, death, or substantial property damage if you ignore the warning.

Preface xxv

EMC uses the following convention for Symmetrix Model 3330/5330 identification:

The Symmetrix 3330-18 and 5330-18 use 3.5-inch disk devices having a formatted capacity of approximately 18 GB. The Symmetrix 3330-9 and 5330-9 use 3.5-inch disk devices having a formatted capacity of approximately 9 GB.

Where to Get Help Obtain technical support for your Symmetrix 3330/5330 by calling your local sales office.

For service on your Symmetrix 3330/5330, call:

(800) 782-4362 (SVC-4EMC)or(800) 543-4782 (543-4SVC)

and ask for Customer Service.

If you are located outside the USA, call the nearest EMC office for technical assistance. These offices are listed at the rear of this manual.

5330-18

DISK CAPACITY (FORMATTED)-18 = 18 GB/DEVICE-09 = 09 GB/DEVICE

SYMMETRIX PRODUCT CLASS

SYMMETRIX 3000/5000 FAMILY3 = 30005 = 5000

DRIVE FORM FACTOR30 = 3.5-INCH

xxvi Preface

Warnings and Cautions

The following warnings and cautions pertain throughout this manual.

WARNING Trained service personnel only.

This unit has more than one power supply cord. To reduce the risk of electric shock, disconnect 2 power supply cords before servicing.

Ground circuit continuity is vital for safe operation of the machine. Never operate the machine with grounding conductors disconnected. Remember to reconnect any grounding conductors removed for or during any installation procedure.

ATTENTION Resérvé au personnel autorisé.

Cet appareil comporte plus d'un cordon d'alimentation. Rafin de prévenir les chocs électriques, débrancher les deux cordons d'alimentation avant de faire le dépannage.

Un circuit de terre continu est essentiel en vue du fonctionnement sécuritaire de l'apareil. Ne jamais metre l'appareil en marche lorsque le conducteur de mise a la terre est débranché.

WARNUNG Nur für Fachpersonal.

Das Geraet hat mehr als eine Anschlussleitung. Zur Vermeidung der Gefahr eines elektrischen Schlages sind vor dem öffnen beide Anschlussleitungen vom Netz zu trennen.

STROMSTREUVERLUST: Gerät muss geerdet werden, bevor es am Stromnetz angeschlossen wird.

Warnings and Cautions xxvii

AdditionalWarnings and

Cautions

Before attempting to service a Symmetrix unit, observe the following additional Warnings and Cautions.

▼ WARNING: The Symmetrix 3330/5330 contains no user-serviceable parts, so it should not be moved or opened for any reason by untrained persons. If the Symmetrix needs to be relocated or repaired, only qualified personnel familiar with safety procedures for electrical equipment and the Symmetrix hardware should access components inside the unit or move the unit.

▼ WARNING: The system operates at high voltages. To protect against physical harm, power off the system whenever possible while servicing.

▼ WARNING: In case of fire or other emergency, isolate the system’s power involved and alert appropriate personnel.

▼ CAUTION: Trained personnel are advised toexercise great care at all times when workingon the Symmetrix unit, and remember to:

• Remove rings, watches, or other jewelryand neckties before you begin anyprocedures.

• Use caution near any moving part and anypart that may start unexpectedly such asfans, motors, solenoids, etc.

• Always use the correct tools for the job.• Always use the correct replacement parts.• Keep all paperwork, including incident

reports, up to date, complete, and accurate.

xxviii Warnings and Cautions

StaticPrecautions

EMC incorporates state-of-the-art technology in its designs, including the use of LSI and VLSI components. These chips are very susceptible to damage caused by static discharge and need to be handled accordingly.

▼ CAUTION: Before handling Symmetrixprinted circuit boards or other Symmetrix partscontaining LSI and/or VLSI components,observe the following precautions:

• Store all printed circuit boards in anti-staticbags.

• Use a ground strap whenever you handle aprinted circuit board.

• Unless specifically designed for non-disruptive replacement, never plug orunplug printed circuit boards with thepower on. Severe component damage mayresult.

Warnings and Cautions xxix

xxx Warnings and Cautions

1

Chapter 1 INTRODUCING SYMMETRIX

This chapter provides an overview of the EMC® Symmetrix® 3330-xx and 5330-xx Integrated Cached Disk Array (ICDA) systems, and highlights their performance, availability, and serviceability features. This chapter also describes hardware and software options.

• Overview.................................................................. 2• Channel Connectivity and Host Integration....... 8• Performance Features........................................... 16• Serviceability Features ......................................... 18• Supported Mainframe Features .......................... 19• Hardware Options ................................................ 22• Software Options .................................................. 23

1

1.1 OverviewSymmetrix is a reliable high performance Integrated Cached Disk Array (ICDA) designed for online data storage. Figure 1 provides a front view of the exterior of the Symmetrix 3330-xx and 5330-xx.

Figure 1. Symmetrix 3330/5330 ICDA

2 INTRODUCING SYMMETRIX

1
Enterprise Storage Architecture: MOSAIC: 2000 and ISA
EMC Enterprise Storage systems rely on MOSAIC:2000® and Intelligent Storage Architecture (ISA) – a combination of industry-standard hardware and software, to ensure optimum performance, availability, scalability and connectivity.

The MOSAIC:2000 architecture is a modular hardware framework (Figure 2) that allows rapid development of new storage technology while supporting existing configurations.

Figure 2. MOSAIC:2000 Architecture

The Intelligent Storage Architecture (ISA) is a modular software framework (Figure 3) that bridges the gaps between platforms, networks, databases, and applications.

Cache

Cache Management

ConfigurationManagement

Traffic Management

ChannelAdapters

CustomerSupportCenter

DiskScrubbing

CacheScrubbing

ContinuousPower

Disk

SCSI Interface

PC Interface

Remote Interface

ApplicationModule

ServiceProcessor

ExpertSystems

Disk Adapters

Overview 3

Together MOSAIC:2000 and Intelligent Storage Architecture (ISA), enable EMC Enterprise Storage systems to:

• Provide high-level performance, capacity and reliability

• Store and retrieve data from all major computing platforms, including mainframe and open systems environments

• Enable software-based functionality that ensures business continuance in the event of a disaster

• Deliver rapid and nondisruptive data migration from one system to another

• Share information, regardless of origin

Figure 3. Intelligent Storage Architecture (ISA)

Database Applications Management

APIs

Connectivity

Information Management

Provides graphical user interfaces to make configuration and management of

storage activity easy.

Business Continuance

Ensuring the highest availability in the event

of planned or unplanned information systems

interruptions.

Performance, Availability

Maintainability,Scalability,

CompatibilityMOSAIC:2000

Information Sharing

Multihost support allows high-speed movement

of large amounts of information between different platforms.

Intelligent Storage Architecture (ISA)


1
Symmetrix 3330/5330 Capacities
The Symmetrix 3330/5330 systems are available with 18 GB or 9 GB disk devices and cache sizes from 512 MBs to 8,192 MBs.

Storage capacities are presented based on the primary methods of data protection:

• Symmetrix Remote Data Facility (SRDF™)• Mirrored (RAID 1)• RAID-S

Tables 1 through 6 list storage capacities for the Symmetrix 3330 and 5330 18 GB and 9 GB systems. For specific storage configurations and recommended cache requirements, refer to Storage Capacities on page 186.1

The GB values shown in Tables 1 through 6 are based on the following conventions:The GB2 value is based on 1 GB = 1024x1024x1024 bytes.

The GB10 value is based on 1 GB = 1000x1000x1000 bytes.

Although these values are expressed differently, they are equivalent.

1. For Symmetrix 3330/5330 3.5-inch 9 GB disk drive capacities attached to AS/400 hosts, contact your EMC sales representative. Currently, the Symmetrix 3330/5330 3.5-inch 18 GB disk drives do not support split 9 GB volume configurations to AS/400 hosts.

Table 1. Symmetrix 3330-18 and 5330-18 SRDF Capacities

18 GB Disk Devices

MainframeStorage Capacities

(GB10)

Open Systems StorageCapacities

(GB2)Open Systems Storage

Capacities (GB10)a

4 to 32 7110 to 57210 672 to 5392 7210 to 57910

Overview 5

.

Table 2. Symmetrix 3330-18 and 5330-18 Mirrored (RAID-1) Capacities

18 GB Disk Devices

Mainframe Storage Capacities

(GB10)


(GB2)


(GB10)a

4 to 32 3510 to 28610 332 to 2692 3610 to 28910

Table 3. Symmetrix 3330-18 and 5330-18 RAID-S Capacities

18 GB Disk Devices



Capacities (GB2)Open Systems Storage

Capacities (GB10)a

4 to 32 5310 to 42910 502 to 4042 5410 to 43410

Table 4. Symmetrix 3330-9 and 5330-9 SRDF Capacities

9 GB Disk Devices

MainframeStorage Capacities

(GB10)



Capacities (GB10)a

4 to 32 3510 to 28610 332 to 2692 3610 to 28910

Table 5. Symmetrix 3330-9 and 5330-9 Mirrored (RAID-1) Capacities

9 GB Disk Devices


(GB10)


(GB2)


(GB10)a

4 to 32 1710 to 14310 162 to 1342 1810 to 14410


1
Table 6. Symmetrix 3330-9 and 5330-9 RAID-S Capacities
9 GB Disk Devices


(GB10)

Open Systems Storage Capacities


Capacities (GB10)a

4 to 32 2610 to 21410 252 to 2022 2710 to 21710

Overview 7

1.2 Channel Connectivity and Host Integration

The Symmetrix 3330/5330 can be integrated with all major enterprise hosts and servers. This section outlines the emulations and hosts Symmetrix supports through parallel and serial channels, Fast-Wide SCSI or Ultra-SCSI channels, and Fibre Channel interfaces.

Symmetrix 3330-xx Channel Connectivity

Symmetrix 3330-xx systems support connectivity to open UNIX®, Windows NT® and AS/400® systems with connectivity to the following interfaces:

• Fast-Wide Differential (FWD) SCSI Interfaces• Ultra-SCSI Channels• Fibre Channels1

When optional EMC Enterprise Storage Platform (ESP) software is added, the Symmetrix 3330-xx Enterprise Systems can simultaneously support connections to mainframe systems with connectivity to ESCON™ Channels.

Symmetrix 5330-xx Channel Connectivity

Symmetrix 5330-xx systems support connectivity to mainframe systems through ESCON or block multiplexer parallel channels. When optional ESP (Enterprise Storage Platform) software is added, the Symmetrix 5330-xx Enterprise Systems can simultaneously support open UNIX, Windows NT and AS/400 systems with connectivity to the following interfaces:

1. Symmetrix does not support Fibre Channel connectivity to AS/400 hosts.


1
• Fast-Wide-Differential (FWD) SCSI Channels• Ultra-SCSI Channels• Fibre Channels1
Symmetrix Channel Configurations

The Symmetrix 3330/5330 systems can be configured with 4 to 16 channels through four 2-port or 4-port channel directors. The following Symmetrix channel directors are available:

• 4-port parallel channel directors (5330-xx systems only)

• 2- or 4-port serial channel directors

• 4-port Fast-Wide-SCSI or 4-port Ultra SCSI directors

• 2-port Fibre Channel directors

Parallel and Serial Channel Interfaces

Symmetrix parallel (5330-xx systems only) and serial channel interfaces attach to IBM® S/370, S/390® (ES/9000®, 309X, 308X, 43XX, and 9370), the plug-compatible manufacturer (PCM) equivalent, Unisys, Bull, and Siemens.

Refer to “Channel Attachments” on page 65 for a more detailed discussion of channel attachment options.

The Symmetrix Enterprise Storage Platform (ESP) software enabler, a software option, is required to store and access mainframe and open systems data on the same Symmetrix. For more information on the ESP option, refer to Symmetrix Enterprise Storage Platform (ESP) on page 30.

1. Symmetrix currently does not support Fibre Channel connectivity to AS/400 hosts.

Channel Connectivity and Host Integration 9

Table 7 shows the IBM DASD models and controllers that Symmetrix emulates.

Mainframe Operating Systems Supported

In IBM/PCM mainframe environments, Symmetrix 3330/5330 is operating system independent. The caching algorithms are self-managed, and Symmetrix does not depend on host cache commands to benefit from read and write caching.

Virtually every System/370 and System/390 operating system can be supported, including:

Symmetrix 3330/5330 also supports the following mainframe operating systems:

Table 7. IBM Controller / DASD Compatibility

IBM Controller

IBM DASD 3880 3990-2 3990-3 3990-6

3380 X X X

3390-1 X X X

3390-2 X X X

3390-3 X X X

3390-9 X X

MVS/ESA™ MVS/XA™ MVS/SP™ ACP/TPF™

VM/ESA™ VM/XA™ VM/SP™ VM/HPO™

VSE/ESA™ VSE/SP™ MVT/VSE™ AIX/ESA™

OS/390™

UTS OS/1100 GC0S7 GCOS8 PICK


1
Fast-Wide SCSI
ChannelInterfaces

When interfaced via FWD SCSI in the open systems environment, the Symmetrix system appears to the hosts as industry-standard SCSI disk devices. Refer to “Fast-Wide and Ultra-Fast-Wide SCSI Channel Attachments” on page 70 for more information about Fast-Wide SCSI channel attachments.

The Symmetrix 3330/5330 channel interfaces attach to a variety of hosts that have SCSI connectivity. Table 8 lists single hosts.

For a list of specific models, operating systems, host adapter cards and information on configuring Symmetrix systems to open system single hosts, refer to the Symmetrix Open Systems Environment Product Guide.


Consult your EMC sales representative for the most current list of supported hosts and EMC’s open systems host support policies.

Table 8. EMC Supported Fast-Wide SCSI Single Hosts

Bull Escala Series M, Series D, Series R, Series RL, Series RL470

DEC™ PCI-based Alphastation™ and Alphaserver™ Series 3000 AXP Models 300-900, 1000, 2000,2100, 4000/4100, 8200,8400

DEC TURBOchannelBus-capable Alpha-based models (Digital UNIX)

DG® AViiON® 5500/88k based

DG AViiON 4900/5900 Intel® based

DG AV4900 AV5900 Pentium® based

Fujitsu DS90 (Japan only)

HP®-3000 900 Series servers

HP9000 700 Series workstations

HP9000 800 Series servers

HP9000 D-Class, K-Class, T600 (SCSI)

IBM RS/6000™, SP2, S70

IBM AS/400 9406 (including RISC-based systems) except Model B a

ICL Smart Controller SDS

NCR® 34xx, 35xx, 3600AP, 41xx45xx, 5100S, 5100C, 5100M

PC: Intel-base Novell and OS/2® servers with Microchannels

PC: Intel® base Novell® and OS/2 servers with EISA bus

PC: Intel-base Novell and OS/2 servers with PCI bus

PC: Intel-base Windows NT servers with Microchannels

PC: Intel-base Windows NT servers with EISA bus

Sequent® Symmetry® 2000 and Symmetry® 5000

Sequent NUMA-Q Seimens® Nixdorf RM400, RM400 C, RM600, RM600 E

Seimens Pyramid® Nile™ Series, RM1000

Silicon Graphics® CHALLENGE® S, L, DM, XL, Origin 200, Origin 2000

Sun™ SPARCServer™ & SPARCcenter™ 10, 20, 1000, 2000

Sun UltraSPARC™, Ultra, Netra, Ultra Enterprise Workstations and Servers

Sun UltraSPARC PCI-based Workstations and Servers

Sun Ultra Enterprise 10000

Sun Ultra Enterprise 450 and PCI-based Servers

Unisys® SMP61000 (Hawk)U6000/XXX, Aquanta Series Servers

a. Refer to your EMC Sales representative for the latest PTF requirements.


1
Ultra SCSI Channel Interfaces
The Symmetrix 3330/5330 Ultra SCSI channel interfaces attach to a variety of hosts that have Ultra-Fast-Wide SCSI connectivity (Table 9).


For a list of specific models, operating systems, and host adapter cards and information on configuring Symmetrix systems to open system hosts, refer to the Symmetrix Open Systems Environment Product Guide.

Table 9. EMC Supported Ultra Fast-Wide SCSI Single Hosts

Bull Series E, Series T, Series RT, Series RL, Series RL470,

DEC™ PCI-based AlphaStation™ and AlphaServer models

HP9000 V-Class V2200 and V2250

IBM RS/6000,SP2, S70 with PCI bus

NCR 4300, 4700 (8-node),and 5150 (128-node) Series

PC: Intel-based Novell or OS/2 servers with PCI bus

PC: Intel-based Windows NT servers with PCI bus

PC: Intel-based HP Netserver models LH, LX, LXR, LXPRO with PCI bus

Silicon Graphics Origin 2000

Sun UltraSPARC, Ultra, Netra, Ultra Enterprise Workstations and Servers

Sun UltraSPARC PCI-based Workstations and Servers


Unisys SMP61000 (Hawk)

Unisys AQUANTA Series Servers


Fibre Channel Interfaces

The Symmetrix 3330/5330 Fibre Channel interfaces attach to several open systems hosts that have Fibre Channel connectivity (Table 10).


SCSI-to-FibreChannel Migration

SCSI-to Fibre Channel migration allows SCSI directors to be upgraded online to Fibre Channel directors while running at microcode revision 5265 or higher. For more information, refer to Online SCSI-to-Fibre Channel Migration on page 130.

Table 10. EMC Supported Fibre Channel Single Hosts

HP9000 D-Class, K-Class, V-Class V2200 V2250

HP9000 T600 PC: Intel-based Windows NT with HP Netserver LH, LX, LXR, LX8R

PC: Intel-based Windows NT with HP and Compaq PC Servers with PCI Bus

PC: Intel-based Windows NT with Compaq Proliant 5000, 6000 HP Netserver LH, LX, LXR

PC: Intel-based Windows NT with Seimens-Nixdorf Primergy 700 NCR PC Server 4300


Sun Ultra Enterprise 450 and PCI-based Servers


1
Supported Cluster Hosts
The Symmetrix 3330/5330 systems attach to a variety of cluster hosts listed in Table 11.


For a list of specific models, operating systems, and host adapter cards and information on configuring Symmetrix systems to open system cluster hosts, refer to the Symmetrix High Availability Product Guide.

Table 11. EMC Supported Cluster Hosts

Bull Escala M1ES, M2ES, M1, M2, M3, X/N, P2204e-T, P2204e-M, P2404e-L, P4404e-L, P8404e-L

Bull Escala EPC-RM, Escala EPC-RTEscala EPC-RL

DEC with Windows NT Alphaserver™ and Intel-based PCs and Alphastation

DEC with Open VMSAlphastations and Alphaserver models 2000, 2100, 4000, 4100, 8200, 8400

DEC PCI bus-based Alphaserver models 400, 800, 1000A, 1200, 2000, 2100, 2100A, 4000, 4000A, 4100, 8200, 8400

DEC VAX HP-9000 (FWD)800 Series: D, E, F, G, H, I, T-500, T-520, K, HP-9000 (FWD)T-600, V-2200, V-2250

HP-9000 (FC-AL)800 Series: D, K, HP-9000 (FC-AL)T-600, V-2200, V-2250

IBM RS/6000, SP/2™, MCA SP/2

NCR® 34xx, 35xx, 36xx, 41xx, 45xx, 5100 Series 4300, 4700, 5150, and 5100 Series

PC: Intel-based Windows NT servers with PCI bus

PC: Windows NT servers with AlphaStations, AlphaServers

Sequent® Symmetry® 2000 and 5000 series and NUMA-Q model

Siemens® Nixdorf RM-400, RM-600, and RM-1000

Sun™ SPARCserver™ and SPARCcenter™ 10, 20, 1000, 2000

Sun UltraSPARC™ SBus workstations and servers, all models

Sun Ultra Enterprise 3x00-6x00, 1000


1.3 Performance FeaturesSymmetrix offers improved performance over conventional Storage Control Unit (SCU) and Direct Access Storage Device (DASD) designs. These Symmetrix features enhance performance and increase throughput:

• Large non-volatile cache• Asynchronous I/O• Multiple storage directors• Parallel processing• 100% Fast Write capabilities• PermaCache option • Hyper-Volume Extension option• Rotational Position Sense (RPS) miss elimination• Segmented device-level buffer• Parallel channel speeds up to 4.5 MB/sec

(5330 only)• Serial channel speeds up to 17 MB/sec• Fast-Wide SCSI channel speeds up to 20 MB/sec• Ultra SCSI channel speeds up to 40 MB/sec• Fibre Channel speeds up to 100 MB/sec• 3380/3390 Mixed Geometry


1
1.4 Availability FeaturesSymmetrix maintains data integrity and maximizes system availability with these features and options:
• Redundant architecture• Full system battery backup• Dual-initiator • Mirroring option• Dynamic sparing option• Non-disruptive component repair • Non-disruptive microcode upgrades• Cache error correction and error verification• Disk error correction and error verification• Error checking, correction and data integrity

protection

Availability Features 17

1.5 Serviceability FeaturesEvery Symmetrix unit has an integrated service processor that continuously monitors the Symmetrix environment. The service processor communicates with the EMC Customer Support Center via a customer-supplied, direct phone line. It automatically dials the Customer Support Center whenever Symmetrix detects a component failure or environmental violation. An EMC Product Support Engineer at the Customer Support Center can also run diagnostics remotely via the service processor to determine the source of a problem and potentially resolve it before the problem becomes critical.

Symmetrix has a modular design with a low parts count for quick component replacement should a failure occur. This low parts count minimizes the number of failure points.

The Symmetrix 3330/5330 features non-disruptive replacement of its major components, including:

• Channel director cards• Disk director cards• Cache cards• Disk devices• Cooling fan modules• Communications cards• Operator panel• Power supplies• Service processor• Battery


1
1.6 Supported Mainframe FeaturesThe following IBM/PCM features are supported on the Symmetrix 3330/5330 that have connections to mainframe hosts:
• Symmetrix Backup/Restore Facility (SBRF)• Multi-Path Lock Facility/Concurrent Access• Multi-System Imaging• Sequential Data Striping• Host Data Compression• Partitioned Data Set Search (PDS) Assist• Dual Copy

SymmetrixBackup/Restore

Facility (SBRF)

The Symmetrix Backup/Restore Facility (SBRF) is fully compatible with IBM’s Concurrent Copy utility. SBRF significantly reduces the time that data on Symmetrix volumes is unavailable during backup operation. SBRF makes the volumes undergoing backup available for I/O activity during Concurrent Copy operation.

SBRF is transparent to the host operating system and host application. SBRF operates on all S/370 and S/390 host computers and applications supporting Concurrent Copy. To use SBRF, the Symmetrix 3330/5330 must be emulating 3990-6 or 3990-3 Storage Control and 3390 DASD with DPR (Dynamic Path Reconnect) and SBRF enabled.

Multi-Path LockFacility/

ConcurrentAccess

Symmetrix supports IBM's Multi-Path Lock Facility/Concurrent Access (MPLF/CA) for use with the ultra-high performance Airline Control Program (ACP) and Transaction Processing Facility (TPF) host operating system environments. MPLF/CA allows multiple concurrent I/O requests to the same logical device from multiple TPF mainframes. The Symmetrix system maintains the names and status of

Supported Mainframe Features 19

logical locks currently in use and responds to requests to obtain or release a lock. This allows multiple hosts to share DASD through multiple paths in an active OLTP environment while maintaining data integrity. MPLF/CA is an enhancement and replacement for the Extended Limited Lock Facility (ELLF) and Limited Lock Facility (LLF).

Symmetrix must be emulating the 3990-6 or 3990-3 storage control and running microcode supporting the MPLF/CA feature.

Multi-Subsystem Imaging

Symmetrix supports multiple System/390 environments by providing maximum connectivity through the use of its 3990-3 and 3990-6 emulation modes and Hyper-Volume Extension feature. For control unit definitions of more than 64 device addresses, it is necessary to define multiple Subsystem IDs (SSIDs). Each SSID has a maximum of 64 devices.

Symmetrix supports up to 16 SSIDs with up to 64 devices per SSID. With certain high-end IBM Enterprise Systems processors, eight-path connectivity may exist to any single device within the Symmetrix configuration.

Sequential DataStriping

Symmetrix is fully compatible with IBM’s Sequential Data Striping function for 3990-6 and 3990-3 storage control with Extended Platform in the parallel or ESCON environment. Sequential Data Striping provides faster batch execution on large I/O-bound sequential processing requests by allowing I/O operations to be managed in parallel across as many as 16 devices.

Sequential Data Striping is available only in DFSMS/MVS environments. Symmetrix must be emulating 3990-6 or 3990-3 storage control and


1
running microcode supporting this feature. Symmetrix must be attached on parallel or ESCON channels, and have SMS-managed volumes.
Host DataCompression

Symmetrix supports IBM’s Host Data Compression feature available on air-cooled Model 511 processor families and water-cooled Model 711 processor families. Symmetrix must be attached on parallel or ESCON channels and running microcode supporting this feature, and the host must be using the Sequential Data Striping function.

Partitioned DataSet (PDS) Assist

Symmetrix supports IBM’s Partitioned Data Set (PDS) Search Assist feature for 3990-6 and 3990-3 storage control with Extended Platform in both ESCON and parallel environments. PDS Assist improves performance on large, heavily-used partitioned data sets by modifying the directory search process. PDS Assist is automatically invoked with the appropriate level of MVS/ESA, MVS/DFP, and DFSMS/MVS, and Symmetrix microcode supporting this feature.

Dual Copy Symmetrix supports IBM’s Dual Copy feature in the MVS environment. Dual Copy allows the host system to establish and maintain an identical copy of data on two physical disk devices in the same Symmetrix unit.

The Dual Copy feature requires that the two devices have the same track geometry and formatted capacity, and are the same emulation type.

Supported Mainframe Features 21

1.7 Hardware OptionsEMC offers the Phone Multiplexer as a hardware option for the Symmetrix 3330/5330.

Phone Multiplexer EMC offers a Phone Multiplexer for domestic customer sites with multiple Symmetrix units. The Symmetrix Phone Multiplexer consists of a PBX with a Direct Inward Systems Access (DISA) board set that switches incoming calls to the correct Symmetrix unit. The Phone Multiplexer allows any mix of Symmetrix units (Models 3xxx, 4xxx, and 5xxx) to use a common telephone line to communicate with the EMC Customer Support Center. Each Symmetrix unit has its own extension in the Phone Multiplexer network.

Consult your EMC Systems Engineer for the latest information on this option.


1
1.8 Software OptionsEMC offers several software options for the Symmetrix 3330/5330 based on their functionality:
• Information Protection• Information Sharing• Information Management• Enterprise Backup Solutions

For more information on each of the EMC software products described in this section, refer to the list of publications in Related Documentation on page xvii in the Preface of this product manual.

Consult your EMC Systems Engineer for the latest information on these options.

Information Protection

EMC provides a variety of information protection/business continuance options, including RAID (Redundant Array of Independent Disks) data protection, Mirroring (the optimum RAID level of both performance and availability), and EMC’s RAID-S enhanced parity protection.

The following information protection software options supplement the standard Symmetrix 3330/5330 information protection options:

Software Options 23

• Symmetrix Remote Data Facility (SRDF™)

• Symmetrix Data Migration Services (SDMS™)

• Non-Disruptive Symmetrix Data Migration Service (ND-SDMS)

• Symmetrix to Symmetrix Open Systems Migration (SSOM)

• EMC TimeFinder™

• EMC CopyPoint™ for AS/400

SymmetrixRemote Data

Facility

The SRDF option is an information protection/ business continuance solution that maintains a mirror image of data at a logical volume level in two to five Symmetrix systems that can be located in physically separate sites.

SRDF offers two disaster recovery solutions:

• Campus Solution• Extended Distance Solution

The SRDF Campus Solution allows Symmetrix units to be located up to 60 km (37.5 miles) apart using fiber-optic links. Synchronous, semi-synchronous, or Adaptive Copy data copying operational modes are available for this solution. This implementation supports both uni-directional and bi-directional SRDF configurations.

The SRDF Extended Distance Solution allows the Symmetrix units to be located over 60 km apart using a T3 or E3 link. Synchronous, semi-synchronous, or Adaptive Copy data copying modes of operation are available for this solution. To minimize the degradation of performance due to distance and telecommunications delays, EMC recommends using the semi-synchronous mode. This implementation mode supports only uni-directional SRDF configurations.


1
SRDF is transparent to the host operating system and host applications. It does not require additional host software for duplicating data on the Symmetrix units at the geographically-separate sites. The participating Symmetrix units manage all SRDF functions. Refer to Symmetrix Remote Data Facility on page 154 for more information.
SRDF FarPoint™. For enhanced SRDF performance in extended distance environments, EMC offers the SRDF FarPoint software option. By improving the utilization of communication line bandwidth, SRDF FarPoint can result in the need for fewer communication lines to remotely mirror information, greatly reducing communication line cost.

The major benefits of FarPoint are:

• Significant application performance improvements

• Better utilization of the extended distance SRDF link

• Fewer Remote Link Directors (RLDs) to achieve increased line utilization

• Fewer SRDF communication links providing a more cost-effective solution

• Batch utilities to provide automatic split and resynchronization of the BCV/R1 volumes over extended distances

SRDF FarPoint significantly enhances Synchronous Mode performance for SRDF extended distance solutions. This allows SRDF Synchronous Mode to be an extremely viable choice for long distance mirroring operations, insuring data consistency between SRDF sites.

Software Options 25

Symmetrix DataMigration Service

(SDMS)

Symmetrix Data Migration Service is a comprehensive planning and execution service and Symmetrix software option that provides continuous business operations and continuous data availability while data is automatically migrated from older mainframe storage devices to a new Symmetrix system.

SDMS is transparent to the host operating system and host applications. It does not require additional host software for duplicating data from the existing DASD or the Symmetrix system.

Mainframe data migration requires the Symmetrix ESP option if the target system is a Symmetrix 3000 model.

The participating Symmetrix units manage all SDMS functions. SDMS, however, does require that a minimum of two of the available four channel director slots in the Symmetrix 3330/5330 be used for its Remote Link Directors during migration.

Non-DisruptiveSymmetrix Data

Migration Service(ND-SDMS)

The Non-Disruptive Symmetrix Data Migration Service (ND-SDMS) is a comprehensive planning, execution service and Symmetrix software option that provides the ability to perform data migration without application (100% application availability) or system(s) interruption. ND-SDMS redirects the I/O from the donor controller to the Symmetrix controller. Data migration then takes place at the Symmetrix level, using no host CPU cycles for the actual migration.

The participating Symmetrix unit(s) manage all SDMS functions. SDMS, however, does require that a minimum of two of the available four channel director slots in the Symmetrix system be used for its Remote Link Directors during migration.

Mainframe data migration requires the ESP option if the target Symmetrix is a 3000 family model.


1
Symmetrix to
Symmetrix OpenSystems Migration

(SSOM)

The Symmetrix to Symmetrix Open Systems Migration (SSOM) application provides the ability to migrate data from Symmetrix subsystems in certain open systems environments. The migration process is transparent to the host platform, operating system and file system. Both the donor and target subsystems must be Symmetrix units.

SSOM is available with Symmetrix 3000 and Symmetrix 5000 systems with ESP. Both the target and donor must be running the same microcode level at revision 5265 or higher. SSOM requires that a minimum of two of the available four channel director slots in the Symmetrix systems be used for its Remote Link Directors during migration.

Open systems data migration is permitted from Symmetrix to Symmetrix systems only and requires the ESP option for 5000 to 3000 or 3000 to 5000 systems migrations. Symmetrix 3000 to 3000 or Symmetrix 5000 to 5000 migrations do not require the ESP option.

EMC TimeFinder(for UNIX, Windows

NT, or MVS BatchUtility)

EMC TimeFinder is a business continuance solution that makes copies of data on standard Symmetrix devices available on special devices called Business Continuance Volumes (BCVs). The BCV devices are made accessible via a separate device address while the original device(s) remain online to their original host(s).

In the UNIX or Windows NT TimeFinder versions, commands for monitor and control functions are provided with a Command Line Interface (CLI). The MVS version provides commands through a batch utility.

BCVs are standard Symmetrix volumes that are pre-configured in the Symmetrix unit on which the business continuation operation will run, and have separate host addresses. A BCV is established as a mirror of the regular Symmetrix volume it supports

Software Options 27

via host commands. Once a BCV pair is established, the BCV device operates as a regular Symmetrix mirror and is not accessible through its separate device address.

The BCV device can be separated, or split, from the mirror group and made available for backup or other host processes through its separate device address.

EMC CopyPoint forAS/400

EMC CopyPoint for AS/400 is a software product for AS/400 hosts that, combined with SRDF, TimeFinder or both, allows a secondary, offline copy of production data to be accessed by a secondary AS/400 system. With CopyPoint, application outages to complete operational tasks, which used to require several hours, are reduced to several minutes - the time needed to complete the split from the production copy of data, which can then be accessed by a secondary AS/400 system.

AutomaticFailover Module

for HPMetroCluster

Automatic Failover Module for HP MetroCluster is an essential component of Hewlett-Packard’s MC/ServiceGuard with MetroCluster software. EMC SRDF functionality is integrated with HP’s MC ServiceGuard high availability software to provide an open systems disaster tolerant solution with automatic failover of applications for geographically dispersed HP-UX clusters.

When a site becomes inoperable due to a system failure or a disaster event, application package switching occurs, automatically transferring control of the impacted application to another host system located in a secondary site, while also automatically read/write enabling remotely mirrored Symmetrix devices associated with the transferred application.

Following are the major benefits of AFM MetroCluster:


1
• Provides rapid site recovery with automatic
failover of application services and automatic read/write enabling of remotely mirrored Symmetrix devices.

• Guards against cluster partitioning during a resynchronization process ensuring only one volume in an SRDF pair is read/write enabled.

• Improves HP 9000 cluster system performance with increased I/O scalability potential as SRDF mirroring and site resynchronization operations consume no host resources.

• Allows cluster distance support between sites up to 40 km with an FDDI intersite link (used to provide heartbeat communication between cluster nodes).

• Reduces site failback time as only changed EMC device tracks are copied back over the network to the second Symmetrix system.

Information Sharing

Symmetrix provides centralized, sharable information storage that supports changing environments and mission-critical applications. Symmetrix technology allows physical devices to be shared between heterogeneous operating environments and extends to specialized software that enhances information sharing between disparate platforms.

The following information sharing options are available in the Symmetrix 3330/5330:

• Symmetrix Enterprise Storage Platform (ESP)• EMC InfoMover™• DataReach™

Software Options 29

SymmetrixEnterprise Storage

Platform (ESP)

The Symmetrix ESP software enabler allows simultaneous storage and access of mainframe data and open systems data on the same Symmetrix 3330-xx or 5330-xx system. ESP allows Symmetrix 3330-xx systems additional connectivity to mainframe devices and for Symmetrix 5330-xx systems, ESP allows additional connectivity to open systems devices.

Each homogenous operating system environment stores its data on its own physical disks, separate from the physical disks used for data storage by other operating systems. In the MVS environment, if the operating system supports shared disk access and integral data integrity features for access to disks from multiple CPUs, then those disks are capable of shared CPU access with Symmetrix ESP. An example is using IBM’s HACMP under AIX with multiple RS/6000 CPUs.

Symmetrix ESP is required to run the software options DataReach, EMC InfoMover and Fast Dump/Restore (FDR).

Refer to the Symmetrix Enterprise Storage Platform Product Guide for more information on Symmetrix ESP. For information on cluster systems, refer to the Symmetrix High Availability Product Guide.

EMC InfoMover(Mainframe

Systems, WindowsNT and UNIX

Servers)

EMC InfoMover software provides high-speed, bulk file transfer between heterogeneous and similar MVS and UNIX-based host systems through a shared Symmetrix Enterprise Storage system. InfoMover supports bi-directional transfer of any files that can be managed through FTP, including flat and non-relational files. InfoMover uses Symmetrix for file transfer rather than a network attachment, utilizing high-speed cache for file transfer.

With InfoMover, files can be transferred among all combinations of MVS and UNIX platforms,


1
including MVS to UNIX, UNIX to MVS, MVS to MVS, and UNIX to UNIX, In this way, InfoMover allows mainframe systems and open systems to have access to information regardless of where it was created. MVS-to-UNIX and UNIX-to-UNIX file transfer rates as fast as 16.5 MB per second for multiple concurrent file transfers can be achieved with all I/O channel types: SCSI, Ultra SCSI or Fibre Channel. InfoMover is designed for bulk transfer and can transfer files both interactively or in automatic batch operations.
InfoMover is installed on each host platform that is to use the software for file transfer. The software can be operated from an MVS Time Sharing Option (TSO) terminal or a UNIX workstation. A transfer may be initiated from either host. The InfoMover server on each host facilitates the transfer. The file transfer occurs through the Symmetrix high-speed cache acting as a staging buffer and transport medium for the files. Because InfoMover uses the high-speed cache of the Symmetrix as well as the multiple shared I/O channels, the transfers occur at very high speeds.

EMC InfoMover software requires the Symmetrix Enterprise Storage Platform (ESP) software option for mainframe-to-UNIX and UNIX-to-UNIX transfers.

DataReach(Mainframe and

UNIX Servers)

DataReach is a software utility that extracts MVS mainframe data and transfers it, at high speed, to a UNIX-based open system. DataReach transfers data from a DB2® database to an open systems database, using a Symmetrix ICDA and an open systems host for data extraction, not the MVS system.

Data extraction occurs through the high-speed cache and SCSI channels of the Symmetrix, rather than through the mainframe CPU and IBM channels. By shifting the work load from the mainframe to

Software Options 31

Symmetrix, DataReach saves valuable CPU time on the mainframe and avoids traffic on the network.

DataReach is installed on an open systems host. It is operated interactively from a Windows NT workstation or run through open systems or MVS scripts.

DataReach allows you to:

• Extract data from a DB2 database and transfer it to an Oracle®, Sybase®, or Informix® database through SCSI channels

• Select the data to be extracted from a database

• Define data extraction from a Windows NT or Windows 95 workstation

• Run DataReach extractions through open systems or MVS scripts

DataReach requires the Enterprise Storage Platform (ESP) software option and at least one of the following Symmetrix configuration options:

• EMC TimeFinder • Symmetrix Remote Data Facility (SRDF)• Direct Connection

Information Management

Symmetrix systems improve information management by allowing users to consolidate storage capacity for multiple hosts and servers. EMC offers powerful graphical user interface (GUI)-based tools that dramatically simplify and enhance Symmetrix configurations, performance, and status information gathering and management.

The following information management options are available in the Symmetrix 3330/5330:


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• Symmetrix Manager - Base Component (for
UNIX, Windows NT, and MVS Agents)

• Symmetrix Manager Workload Analyzer

• Symmetrix Manager - SRDF Component (for UNIX or Windows NT)

• SRDF Host Component (MVS/ESA Environment)

• Symmetrix Manager - TimeFinder Component (for UNIX or Windows NT)

• Symmetrix Manager - SDDR Component (for UNIX or Windows NT)

• EMC Solutions Enabler Overview

• EMC Solutions Enabler SYMCLI Base Component

• EMC Solutions Enabler SYMCLI SRDF Component

• EMC Solutions Enabler SYMCLI TimeFinder Component

• EMC PowerPath™ (Open Systems Environment)

SymmetrixManager - Base

Component(with UNIX,

Windows NT andMVS Agents)

The Symmetrix Manager - Base Component is a host application software package for obtaining the status of and monitoring the performance of a Symmetrix unit attached to that host. It has two user interfaces:

• SM-GUI - a Motif® or Windows NT based, graphical user interface (GUI)

• SM-CLI - a Symmetrix Manager Command Line Interface (CLI) that consists of a library of commands executed from the host console

Software Options 33

Symmetrix Manager provides tools for the following areas:

• Monitoring Symmetrix operation

• Viewing Symmetrix performance (current or archived)

• Viewing Symmetrix configuration

• Checking the error codes and severity levels monitored by the Symmetrix Manager

• Monitor and control multiple Symmetrix units from a single workstation with SymmConsole

SymmConsole uses an SMNP manager/agent network configuration. The host running SymmConsole is the manager, which has a network connection to host machines with agents (for Windows NT, UNIX, or MVS) installed on them.

SymmetrixManagerWorkloadAnalyzer

This option is a post-processing tool that complements the real-time reporting of component-level performance data available in Symmetrix Manager-Base Component. Workload Analyzer allows a storage administrator to collect, analyze and graph historical performance data in order to help identify performance trends or implementation deficiencies.

Symmetrix Manager-Base Component is a prerequisite for the Workload Analyzer option.

SymmetrixManager - SRDFComponent (for

UNIX orWindows NT)

The Symmetrix Manager - SRDF Component is an add-on host application software package to Symmetrix Manager. The SRDF Component allows you to monitor SRDF Symmetrix status and perform SRDF operations.


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As with the Symmetrix Manager - Base Component, the SRDF Component also has SM-GUI - Symmetrix Manager - Graphical User Interface and SM-CLI - Symmetrix Manager - Command Line Interface.
Symmetrix Manager - SRDF allows you to perform integrated SRDF operations by selecting the desired operational mode in SM-GUI or by running special scripts provided with SM-CLI from a UNIX command line.

The SRDF integrated operations include:

• Failover operation• Basic SRDF operations• Concurrent operation at both Symmetrix units in

an SRDF configuration

To use Symmetrix Manager - SRDF Component, you must have Symmetrix Manager - Base Component and Symmetrix Manager - SRDF Component installed on your UNIX or Windows NT host. Your Symmetrix systems must also be configured for SRDF operation.

SRDF HostComponent

(MVS/ESAEnvironment)

SRDF Host Component for mainframe systems is an MVS subsystem that monitors SRDF status and controls SRDF processes. The SRDF Host Component commands are executed at the host console. The SRDF Host Component features the SRDF command set.

The SRDF feature maintains a mirror image of data at the logical volume level in two to five Symmetrix systems which can be located in physically separate sites. SRDF requires that a minimum of two of the available channel director slots in the Symmetrix be used for its Remote Link Directors (RLDs). Refer to Symmetrix Remote Data Facility on page 154.

Software Options 35

SymmetrixManager -TimeFinder

Component (forUNIX or

Windows NT)

Symmetrix Manager - TimeFinder Component is a host application software package for obtaining the status of and monitoring the performance of a Symmetrix unit attached to that host. The TimeFinder component allows you to control and monitor TimeFinder business continuance operations through a Graphical User Interface (GUI).

As with the Symmetrix Manager - Base Component, the TimeFinder Component also has SM-GUI - Symmetrix Manager - Graphical User Interface and SM-CLI - Symmetrix Manager - Command Line Interface.

To use Symmetrix Manager - TimeFinder Component, you must have Symmetrix Manager - Base Component and Symmetrix Manager - TimeFinder Component installed on your UNIX or Windows NT host. Your Symmetrix must also be configured for TimeFinder operation.

SymmetrixManager - SDDRComponent (for

UNIX orWindows NT)

The Symmetrix Dynamic Device Reallocation (SDDR) facility allows you to reallocate Symmetrix logical volumes. Using SDDR, you can perform move, delete, add, and modify operations on various Symmetrix devices, including FBA devices, Business Continuance Volumes (BCVs) and Meta devices.

The SDDR component cannot reallocate Symmetrix mainframe (CKD) devices.

As with the Symmetrix Manager - Base Component, the SDDR Component also has the SM-GUI - Symmetrix Manager - Graphical User Interface. However, the Symmetrix Manager - SDDR Component does not have the SM-CLI - Symmetrix Manager - Command Line Interface.


1
To run SDDR, you must have Symmetrix Manager - Base Component and Symmetrix Manager - SDDR Component installed on your UNIX or Windows NT open systems host.
EMC SolutionsEnabler Overview

EMC Solutions Enabler provides the essential Symmetrix interface component for a variety of Enterprise Storage management and business continuance software solutions. The Solutions Enabler kit comprises a set of runtime libraries, the Symmetrix Command Line Interface (SYMCLI) and a License Management Facility.

The Solutions Enabler provides command line interface and/or application program interface to several unique Symmetrix functions, controlled by a built-in key mechanism. Advanced functionality, such as TimeFinder and SRDF can be enabled by additional keys provided with specific software solution packages. For example, EMC’s Automatic Failover Module for HP MetroCluster includes the Solutions Enabler with a key to enable the SRDF and TimeFinder functions required to implement the Hewlett-Packard MC/ServiceGuard with MetroCluster solution. Refer to Automatic Failover Module for HP MetroCluster on page 28.

EMC SolutionsEnabler SYMCLI

Base Component

The EMC Solutions Enabler SYMCLI Base Component software provides the host with a SYMAPI shared library and a special Command Line Interface (SYMCLI). The SYMCLI works on Windows NT and various UNIX platforms.

The Symmetrix Command Line Interface (SYMCLI) allows you to run commands on the host in order to obtain configuration, status, and performance data from the Symmetrix units attached to hosts that are running in an open systems environment.

Software Options 37

SYMCLI resides on a host system and retrieves data from a Symmetrix unit by sending the Symmetrix special low-level SCSI commands. SYMCLI commands are invoked from the host operating system.


SRDF Component

The EMC Solutions Enabler SYMCLI SRDF Component software contains the SYMCLI Base Component commands and the symrdf command that allow you to perform the following control operations of SRDF devices:

• Establish (mirror) an SRDF pair by initiating a data copy from the source side to the target side.

• Restore remote mirroring. Initiates a data copy from the target to the source

• Split an SRDF pair, which stops mirroring for the SRDF pair in a device group.

• Failover from the source side to the target side, to allow data processing to the target side.

• Failback from the target side to the source side, to allow data processing to the source side.

• Update the source side after a failover, while the target side may still be operational to its local hosts.


1
Additionally, the symrdf command performs operations including:
• Setting the SRDF mode for one or more SRDF pairs in a device group

• Returning information about the state of SRDF mirroring

• Linking one or more Symmetrix units locally or remotely via SRDF links

• Singular SRDF control operations, which are the individual operations that comprise the complete SRDF control actions.


TimeFinderComponent

The EMC Solutions Enabler SYMCLI TimeFinder Component software contains both the SYMCLI and the symmir command that allows you to perform the following control operations on BCVs (Business Continuance Volume) devices

• Establish (mirror) one or all standard devices in a device group with one or more BCV devices that are associated with the group.

• Restore one or all standard devices in a device group from one or more BCV devices that are associated with the group.

• Split one or all BCV devices from the standard device(s) in a device group.

• Return information about the state of mirroring of one or all BCV device pairs in a device group.

EMC PowerPath(Open Systems

Environment)

EMC PowerPath is server-based software that works in conjunction with Symmetrix. PowerPath enhances Symmetrix capabilities by providing automatic detection of and recovery from server-to-Symmetrix connection failures.

Software Options 39

PowerPath enables you to establish from 2 to 32 SCSI paths between an open system host and a Symmetrix device configured for the server. You can use these paths simultaneously for data I/O to the device.

If a failure occurs on any path, PowerPath automatically redirects data over the other paths without disrupting I/O.

In addition, PowerPath allows you to balance the distribution of the I/O load to improve performance. You can configure data paths, maintain the paths, and tune for performance while online.

EMC Enterprise Backup Solutions

Enterprise Backup Solutions is the integration of EMC’s SRDF and TimeFinder with backup solutions from EMC and other vendors. These partner applications enable non-disruptive, point-in-time backup of corporate databases and applications.

Symmetrix systems support EMC SRDF and TimeFinder integrated with the following enterprise backup products:

• EMC Data Manager (EDM™), EMC Corporation

• FDRSOS™, from Innovation® Data Processing

• FDR® InstantBackup from Innovation Data Processing

• Legato NetWorker® from Legato® Systems, Inc.

• HP OpenView® OmniBack II from Hewlett-Packard Company (EMC Symmetrix Remote Data Facility (SRDF) TimeFinder integration)


1
The following sections describe these backup solutions from EMC and their partners.
For more information on EMC TimeFinder integration with the products above, refer to the EMC Enterprise Backup Solutions Product Guide.

EDM - EMC DataManager (Open

SystemsEnvironment)

EDM is a centralized open systems high-performance database backup system. EDM is a fully integrated package that includes all hardware, software, and service support. It completely automates tasks such as scheduling, tape management, and offsite disaster media storage.

Network EDM fully supports most UNIX vendors as well as OS/2, NetWare, and Windows NT servers. Additionally, network EDM supports database backup and restore, both online and offline, for major database vendors such as Oracle, Sybase, Informix, and Microsoft’s SQL.

As an alternative to network backup, EDM permits direct Symmetrix connectivity to client data storage. With direct Symmetrix connectivity, EDM and Symmetrix handle all of the backup data movement, off-loading most backup processing from mission-critical systems and the network. EDM with direct Symmetrix connectivity offers the best solution for data centers running Oracle VLDBs or data centers in which backup cannot be done over the network.

EDM can be used with either EMC TimeFinder or SRDFwith the following advantages:

• TimeFinder Backup allows the backup solution to do a point-in-time backup directly from Symmetrix, while allowing customers continued 24x7 access to their applications.

Software Options 41

• EDM Symmetrix Connect uses TimeFinder or SRDF remote mirroring software to establish a mirror image of the database on a physically separate Symmetrix system.

FDRSOS Option(Open Systems

and Mainframe)

FDRSOS™ (Fast Dump Restore Safeguard Open Storage) is a storage management software option that provides high speed, full volume backup and restore of open systems (SCSI) volumes to mainframe (MVS) tape or disk storage.

FDRSOS runs under MVS XA, ESA, and OS/390 operating systems with a Symmetrix system. FDRSOS requires the Symmetrix ESP (Enterprise Storage Platform) software enabler, which provides mainframe access to both MVS and open systems format DASD at high performance ESCON channel speeds.

FDRSOS was developed under a joint agreement with Innovation Data Processing® and EMC corporation and is available from Innovation. FDRSOS is an extension of Innovation Data Processing’s FDR® family of storage management products. EMC Symmetrix systems allow access to data from both SCSI and S/390 channels, while IDP produces software (FDRSOS) that can be run on MVS to back up and restore this data.

FDR/Upstream/SOS creates a backup on the open systems portion of the Symmetrix system and makes it available for copying directly to S/390-controlled tape storage, thus eliminating network transmission of the information. Following a full backup, regular incrementals can be done. Since an incremental backup identifies and backs up only the information that has changed since a previous backup, less time is taken for backup enabling more time for other important enterprise support functions.


1
FDR Instant
BackupFDR InstantBackup is an FDR facility from Innovation Data Processing for nondisruptive full-level backup with full volume restore as well as powerful logical file restore for offline mainframe data. When FDR InstantBackup is integrated with EMC TimeFinder, an EMC product that creates point-in-time nondisruptive exact duplicates of existing DASD volumes without transferring data across host channels.

HP OpenViewOmniBack II

HP OpenView OmniBack II is a data and database backup and recovery solution from Hewlett-Packard (HP) Company. It is designed to facilitate rapid, reliable, automated backup and recovery in distributed, open systems environments. HP has added the capability to provide integrated support for SRDF- and TimeFinder-based backups from within OmniBack II.

OmniBack II provides automated backup and recovery of SRDF and TimeFinder volumes while the user continues to have access to the data. OmniBack II complements the disaster recovery capabilities provided by SRDF by allowing customers to automatically recover the environment to any previous point in time (previous backup version). OmniBack II also brings to the SRDF/TimeFinder environment its integration with data base products, as well as OpenView, SAP, and file systems.

Legato NetWorkerfor EMC Symmetrix

Legato NetWorker is an integrated, scalable family of storage management software that provides data protection and storage management services for networks of all sizes. NetWorker produces mission-critical data protection by providing backup, recovery, archive and automated disaster recovery for file/print, database, and application servers and their networked clients -- regardless of platform or operating system. Legato NetWorker storage

Software Options 43

management software is developed by Legato Systems, Inc.

NetWorker for EMC Symmetrix is a specialized adaptation of Legato NetWorker that integrates with EMC Timefinder and/or SRDF to provide database-aware split-mirror backup of a targeted application from a secondary host machine, thus minimizing any disruption to the production host environment. The integration allows users to create separately addressable copies of their production database and perform high speed backup from a second host while the production application remains on line and fully available to users.


2
Chapter 2 SYMMETRIX 5330/3330 HARDWARE
This chapter describes the main hardware components of the Symmetrix 5330/3330 ICDA including:

• Major Components ............................................... 46• Operator Panel ...................................................... 49• Disk Devices .......................................................... 51• Directors and Cache ............................................. 58• Channel Attachments........................................... 65

45

2.1 Major ComponentsThe Symmetrix 5330/3330 is a disk subsystem that houses all Storage Control Unit functions and DASD in a single cabinet. This section describes:

• Component Overview• Symmetrix 5330/3330 Block Diagram

Figure 4 shows the location of the main components of the Symmetrix 5330/3330.

Figure 4. Symmetrix 5330/3330 (Interior View)

COOLING FANMODULES

POWER SUBSYSTEM

SERVICE PROCESSOR

DISK DEVICES

BATTERY SUBSYSTEM

DIRECTOR AND CACHE CARDS, FRONT

ADAPTER CARDS,REAR

46 SYMMETRIX 5330/3330 HARDWARE

2

Component Overview

These components have the following functions:

Cooling Fan Modules. Contains fans for maintaining air circulation and cooling the unit internally.

Card Cage and Backplane. Accommodates up to eight director, cache, and adapter cards. The directors and cache cards connect to the front of the backplane. The adapter cards connect to the rear of the backplane.

Disk Devices. Contains up to 32 3.5-inch disk devices for data storage. Symmetrix 3330-18 and 5330-18 offer 18 GB disk devices. Symmetrix 3330-9 and 5330-9 offer 9 GB disk devices.

(5330) Bus & Tag Connector Panel. Connectors for bus and tag cables that serve as the external interface to mainframe hosts.

Battery Subsystem. Maintains power for three minutes to the entire subsystem if AC power fails.

Power Subsystem. Two power supplies provide +5V, +12V, and +24V power to the Symmetrix components.

Ethernet Hub. The Ethernet board allows the Symmetrix to communicate with each disk director or channel director. It is located just below the service processor.

Integrated Service Processor. Downloads the Symmetrix configuration to the directors and provides diagnostic and maintenance utilities for Symmetrix. It connects to the Symmetrix subsystem via an RS-232 interface and/or an Ethernet Hub and uses an external modem for communicating with the EMC Customer Support Center when Symmetrix detects an error condition.

Major Components 47

Dual Power Cords. EMC offers dual power cords on the Symmetrix 5330/3330. This allows you to connect the power subsystem to two dedicated or isolated power lines.

Symmetrix 5330/3330 Block Diagram

Figure 5 illustrates the interconnection of the major components of the Symmetrix 5330/3330.

Figure 5. Symmetrix 5330/3330 Block Diagram


2

2.2 Operator PanelThis section describes the functions of the various operator panel components.

The Symmetrix 5330/3330 operator panel is located at the top of the front door. It has two displays: one for the disk directors and one for the channel directors. Figure 6 shows an example of the operator panel.

Figure 6. Operator Panel

Disk Director Display

The disk director display (Figure 6) is located on the left side of the operator panel.

The disk director display has an Enable/Disable switch for each disk director. This switch places the disk director in an online or offline state.

When a switch is in a disabled position, the host system sees all disk devices physically connected to that disk director in a not ready (“Intervention Required”) state and the hex display on the disk director indicates “0F”.

Operator Panel 49

Channel Director Display

The channel director display is located on the right side of the operator panel (Figure 6). There is a separate display for each channel director.

The operator panel displays the current activity and status of each channel director. The switches control physical channel online/offline activity.

The channel director display components function as follows for the channel directors:

POWER. LED indicating that the operator panel is receiving power.

ACTIVE/READY LED. LED indicating channel activity. When the Active/Ready LED is lit, that channel interface is online to the host system. When the Ready/Active LED is flashing, I/O operations are in progress. For remote link directors (SRDF), these LEDs have no meaning.

ENABLE/DISABLE SWITCHES. Switch for placing a channel interface in the online or offline state to the host system. When the switch is in the ENABLE position, that channel interface is online to the host system. When the switch is in the DISABLE position, that channel interface is offline to the host system


2

2.3 Disk DevicesSymmetrix systems use industry-standard SCSI Head Disk Assemblies (HDAs) in the physical disk devices. Each HDA is configured with its own controller consisting of control logic, a microprocessor, and a device-level buffer.

The device-level buffer is designed to eliminate Rotational Position Sensing (RPS) misses. An RPS miss occurs when the head or current rotational position of the disk media is such that the transfer is possible when requested, but the controller and its path to the HDA are not available. An RPS miss typically causes a time delay for transfer of at least one additional rotation of the disk. Through the use of the device-level buffer, data is easily moved between the disk director or the drive media and the buffer. This enables an electronic transfer between the buffer on the HDA and the disk director, thereby avoiding the possibility of an RPS miss.

The device-level buffer can also be segmented, using the SCSI-2 command set. This allows Symmetrix control logic to issue a read command to the device, detach, then issue a data write to a different segment of the device-level buffer. The on-board microprocessor will manage the read or write, and will notify the Symmetrix system when the read is complete.

The Symmetrix 5330/3330 uses 3.5-inch disk devices, each having a storage capacity of approximately 18 GB or 9 GB. The Symmetrix 5330/3330 can contain up to 32 disk devices. The formatted capacity of the disk devices determines the emulations configurable on that device.

Disk Devices 51

Symmetrix emulates IBM DASD for IBM/PCM hosts, and standard SCSI disk devices for open systems hosts. The following sections describe the Symmetrix disk formats emulated for each type host.

Symmetrix 3330 Disk Device Emulations

Symmetrix 3330 disk devices emulate standard SCSI disk devices when interfacing with open UNIX, Windows NT and AS/400 systems hosts. When optional ESP (Enterprise Storage Platform) software is added, the Symmetrix 3330 Enterprise Systems can simultaneously support connections to mainframe systems.

Symmetrix 5330 Disk Device Emulations

Symmetrix 5330 disk devices emulate IBM DASD when interfacing with IBM/PCM hosts. When optional ESP (Enterprise Storage Platform) software is added, the Symmetrix 5330 Enterprise Systems can simultaneously support connections to open UNIX, Windows NT and AS/400 systems.

Open Systems SCSI Disk Emulation

On open systems hosts, Symmetrix 3330 (and 5330 with ESP) logical disk volumes appear to the host as physical disk devices at SCSI target ID/logical unit number addresses. All host logical volume manager software can be used with Symmetrix disk volumes.

When using a Fast-Wide SCSI or Ultra SCSI interface to an open system processor, the Symmetrix system appears as standard SCSI disk devices with data stored in fixed-block architecture (FBA) format.

The following paragraphs describe the Fast-Wide SCSI disk format and logical volume structure.


2

FBA Data andCommand Format

(Open SystemsOnly)

FBA disk devices store data in fixed sized blocks (typically 512 bytes) 1. A disk device using FBA format is viewed as a large array of blocks. The physical position of the block (cylinder and track) is usually not significant to the host. When requesting disk access for read or write, the host addresses a file by the logical block address (LBA) of the starting block and a count of the total blocks used by the file.

Symmetrix SCSI channel directors and disk directors control access to cache and disk devices, responding to host requests as a standard SCSI disk device.

Logical VolumeStructure (Open

Systems Only)

The channel directors interact with cache. Therefore, there is no mechanical meaning to cylinders, tracks, and heads on the Symmetrix logical volume from the front end point of view.

However, Symmetrix uses a logical geometry definition for its logical volume structure. This geometry is reflected in the SCSI mode sense data available to the host.

Symmetrix uses the following logical volume structure:

• Each logical volume has N cylinders• Each cylinder has 15 tracks (heads)• Each track has 64 blocks of 512 bytes

Therefore, a Symmetrix logical volume with N cylinders has a usable block capacity of:

N * 15 * 64

“N” for each volume is defined during Symmetrix configuration.

1. Disk devices in Symmetrix 3330-9 and 5330-9 systems attached to AS/400 hosts are configured in 520-byte blocks. In Symmetrix systems with a mix of AS/400 and other open systems hosts, all disk devices must be configured in 520-byte blocks.

Disk Devices 53

To calculate the size of the logical volume:

# of Cylinders * Heads * Blocks * 512(N * 15 * 64 * 512)

For information on configuring open systems logical volumes, refer to Open Systems Hyper-Volumes on page 95.

IBM DASD Disk Emulation

The Symmetrix 5330 system and the Symmetrix 3330 system with ESP appear to mainframe operating systems as a 3990-6, 3990-3 or 3990-2 controller. The physical disk devices can appear to the mainframe operating system as a mix of multiple 3390 and 3380 device types. All models of the 3380 or 3390 volumes can be emulated up to the physical volume sizes installed. A single Symmetrix system can simultaneously support both 3380 and 3390 device emulations.

Table 12 lists the Symmetrix characteristics for some standard IBM device emulation modes. The Symmetrix 5330/3330 also supports non-standard device sizes as long as the cylinder count does not exceed that of the equivalent IBM device type.

Table 12. IBM DASD Emulation Characteristics

IBM DASD Model MB/ Volume Bytes/ Track Bytes/ Cyl Cylinders/Vol

3390-9 8,514 56,664 849,960 10,017

3390-3 2,838 56,664 849,960 3,339

3390-2 1,892 56,664 849,960 2,226

3390-1 946 56,664 849,960 1,113

3380K 1,890 47,476 712,140 2,655

3380K+ 2,378 47,476 712,140 3,339

3380K++a 2,843 47,476 712,140 3,993

a. Not supported by VM/ESA 1.2.1 (and 1.2.2). Support of this emulation type depends on the operating system in use.


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Mixed TrackGeometries

A Symmetrix 5330/3330 is configurable with both 3380 and 3390 track geometries on the same disk device.

A single Symmetrix disk device may contain up to 32 logical volumes and up to 1,024 logical volumes per system.

For information on configuring mainframe logical volumes, refer to Mainframe System Hyper-Volumes on page 101.

IBM/PCM Dataand Command

Formats

All Symmetrix models support the count-key-data (CKD) and extended count-key-data (ECKD) format used by IBM 3390 and 3380 DASD. For a full description of the channel command words (CCW) supported, refer to IBM 3990 Storage Control Reference or the IBM 3880 Storage Control Model 13 Description.

Figure 7 shows the CKD track format emulated for 3390 and 3380 DASD.

Figure 7. Track Format for 3390 and 3380 DASD

Track Format. All tracks are written with formatted records. The start and end of each track are defined by the index marker. Each track has the same basic format as that shown in Figure 7. That is, it has an index marker, home address (HA), record zero

Disk Devices 55

(R0), and one or more data records (R1 through Rn). These track formats are discussed in the following paragraphs.

Information is recorded on all Symmetrix disk devices in an emulation format chosen at configuration. Each track contains certain “non-data” information (such as the address of the track, the address of each record, the length of each record, and the gaps between each area), and data information.

Index Marker. For each disk device, there is one index marker to indicate the physical beginning and end of each track.

Home Address (HA). There is one Home Address on each track that defines the physical location of the track by specifying the track address (cylinder and head location) and the condition of the track (flag byte). The flag byte indicates whether the track is usable, defective, or an alternate track.

Record Zero - R0 (Track Descriptor Record). This is the first record after the Home Address. The Count field indicates its physical location (cylinder and head), record number, key length, and data length. In general, the Key length is 0 bytes and the Data length is 8.

Data Records (R1 through Rn). All remaining records on a track are data records. The Count field indicates the data record's physical location (cylinder and head), record number, key length, and data length. The Key is optional and when used contains information used by an application. The data area contains the user data. To determine the number of records a track can hold, refer to the IBM 3390 Direct Access Storage Introduction or IBM 3380 Direct Access Storage Introduction for the equations for calculating this number.


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Track Capacity This is the maximum capacity achievable when there is one physical data record per track formatted without a key. Since the track can contain multiple data records, additional Address Markers, Count Areas, and gaps reduce the number of bytes available for data.

The track capacity is the number of bytes left for data records after subtracting the bytes needed for the Home Address, Record Zero, Address Marker, Count Area, Cyclic Check (for error correction) and the gaps for one data record.

For 3390 emulations, the track capacity is 56,664 bytes. For 3380 emulations, the track capacity is 47,476 bytes.

Disk Devices 57

2.4 Directors and CacheThe channel directors and cache manage the storage control functions. The disk directors handle the data storage functions. This section describes the Symmetrix 5330/3330 channel directors, disk directors, and cache cards.

Channel Director Connectivity

All Symmetrix systems provide channel connectivity through combinations of channel directors. These include serial channels, parallel channels (5330 systems only), Fast-Wide-Differential SCSI and Ultra-SCSI channels, Fibre Channels, and Remote Link Channel Directors (used with SRDF and SDMS). Symmetrix systems connect directly to host processors through physical path types or physical channel attachments.

The Symmetrix 3330, and the Symmetrix 5330 with ESP, support open UNIX systems, Windows NT systems, and AS/400 connectivity through Symmetrix FWD SCSI, Ultra-SCSI, and Fibre Channel directors.

The Symmetrix 5330, and Symmetrix 3330 with ESP, support mainframe connectivity through serial channel directors for ESCON connections and parallel channel directors (5330 systems only) for block multiplexer connections.

When Symmetrix ESP software is installed on a Symmetrix 3330 or 5330 system, simultaneous connections for mainframes, UNIX, Windows NT, and AS/400 systems are provided.


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Channel Director Descriptions

Symmetrix channel directors are single cards that occupy one slot on the Symmetrix backplane. All channel directors, except parallel channel directors, interface to host channels via interface adapter cards connected to the opposite side of the backplane. Parallel channel directors interface to hosts via block multiplexer channels through bus and tag connector panels located in the bottom of the Symmetrix cabinet.

The Symmetrix 3330/5330 supports two to four channel directors. All channel directors contain two advanced microprocessors that process data from the host and manage access to cache.

Each parallel or serial channel director supports two concurrent I/Os (up to 8 concurrent I/Os per system). Each Fast-Wide SCSI or Ultra SCSI channel director supports 4 concurrent I/Os (up to 16 concurrent I/Os per system). The Fibre Channel director supports two concurrent I/Os (up to 8 concurrent I/Os per system).

Table 13 on page 60 defines configurations for Symmetrix channel directors.

Table 13 defines capacity of a single channel director card that holds two microprocessors (Processors). A channel director’s configuration determines the number of logical devices that the host can access. Different types of channel directors can support different amounts of logical devices, and Logical Paths (LPaths). The number of LPaths used will affect the number of devices that a director can support.

The sections following Table 13 describe each of the Symmetrix channel directors.

Directors and Cache 59

Table 13. Channel Director Configurations

Director Typea

Ports per Processor

Processors per Board

Logical Vols. per Processor

Logical Paths per

Port

Logical Volumes per Board

Logical Paths per

Board

CA2 2 2 256/Port 1 1,024 4

EA1 1 2 512 28 1,024 56

EA1 1 2 497 29 994 58

EA1 1 2 488 30 976 60

EA1 1 2 474 31 948 62

EA1 1 2 466 32 932 64

EA2 2 2 512 14 1024 28

EA2 2 2 488 15 976 30

EA2 2 2 466 16 932 32

EA2 2 2 446 17 892 34

EA2 2 2 428 18 856 36

EA2 2 2 411 19 822 38

EA2 2 2 395 20 790 40

EA2 2 2 381 21 762 42

EA2 2 2 367 22 734 44

EA2 2 2 355 23 710 46

EA2 2 2 343 24 686 48

EA2 2 2 332 25 664 50

EA2 2 2 322 26 644 52

EA2 2 2 312 27 624 54

EA2 2 2 303 28 606 56

EA2 2 2 295 29 590 58

EA2 2 2 286 30 572 60

EA2 2 2 279 31 558 62

EA2 2 2 272 32 544 64

SA2 2 2 240/Port - 960 -

FA 1 2 128 - 256 -

a. Director Type Key: CA2: 4-port Parallel Channel Director; EA1: 2-port Serial Channel Director;EA2: 4-Port Serial Channel Director; SA2: 4-port FWD SCSI or Ultra-SCSI Channel Director;FA: 2-port Fibre Channel Director


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Fast-Wide SCSIChannel Director

The Fast-Wide-Differential (FWD) SCSI director has four differential wide interfaces for connection to open system hosts and one high-speed path to cache.

FWD SCSI channel directors support data transfer rates up to 20 MB/sec. Each SCSI director can support up to 960 logical volumes (with a maximum of 1,024 logical volumes per Symmetrix system).

Ultra SCSI Director The Ultra SCSI director has four differential wide interfaces for connection to host systems and one high speed path to cache.

The Ultra SCSI director supports data transfer rates up to 40 MB/sec with a host over each channel interface simultaneously. Each SCSI director can support up to 960 logical volumes (with a maximum of 1,024 logical volumes per Symmetrix system).

Fibre ChannelDirector

The Fibre Channel director has two FC ANSI compliant 1 Gigabit Fibre Channel interfaces for connection to open systems hosts and one high speed path to cache. The Fibre Channel SCSI protocol mapping and upper level protocol layers are both implemented within the director.

The Fibre Channel director supports a data transfer rate of up to 100 MB/sec. with a host over each channel interface simultaneously. Each Fibre Channel director can support up to 512 logical volumes (with a maximum of 1,024 logical volumes per Symmetrix system).

Symmetrix Fibre Channel directors currently support connections to a number of hosts supporting Fibre Channel connectivity. For a current list of supported hosts, contact your EMC Sales representative.


Parallel ChannelDirector

(5330) The parallel channel director is a single card that has four paths (parallel channel interfaces) to the host system and one path to cache. It contains two advanced microprocessors that process Channel Command Words (CCWs) from the host and manage access to cache. The channel data transfer rates are microcode-configurable for 1.0 to 1.5 MB/sec, 3.0 MB/sec, or 4.5 MB/sec.

Each parallel channel director supports up to 256 logical volumes per port, for a maximum of 1,024 logical volumes per director. The Symmetrix 5330 supports a maximum of 1,024 logical volumes per system.

Serial ChannelDirector

The serial channel director processes frames from the mainframe host and manages access to cache. The serial channel director supports data transfer rates up to 17 MB/sec with the host. With the IBM ESCON Multiple Image Facility (EMIF) Symmetrix can contain up to 512 different images. EMC offers two-port and four-port serial channel directors, each of which can support up to 1,024 logical volumes per board.

Symmetrix serial channel directors support 2 Control Unit Address (CUADD) images, 512 logical devices per ESCON port and 32 separate logical paths (LPaths) addressable to one port. The 32 logical paths may be shared in any fashion between the 2 CU images. For example, all 32 logical paths can be configured on one CU image and none on the other. Or, 32 logical paths may be split between the ports (for example, 18 on CUADD 0 and 14 on CUADD 1) For LPAR configurations, refer to Table 13 on page 60.

Remote LinkDirector

The Remote Link Director (RLD) is a 2-port or 4-port serial channel director microcode-configured as the link between Symmetrix units in a Symmetrix


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Remote Data Facility (SRDF) or Symmetrix Data Migration Service (SDMS) configuration. The Remote Link Director (RLD) interfaces to Symmetrix channels via a serial channel interface adapter.

The Remote Link Director supports data transfer rates up to 17 MB/sec. EMC offers two-port and four-port Remote Link directors, each of which can support up to 1,024 logical volumes per board. Symmetrix requires a minimum of two and supports up to four RLDs in each Symmetrix 3330/5330 unit used in an SRDF or SDMS configuration. A two-port RLD (one port on each processor) can be configured as two remote links to other Symmetrix units. Or, one port can be configured as an RLD and the second port can be configured as a serial port.

When one of the processors of a four-port RLD (two ports on each processor) is configured as an RLD, only one of the ports on that processor can be configured as a remote link, while the remaining port is not used. The second processor can be configured as a serial director, with both ports being used for serial channels. If two ports of the four-port RLD are needed as remote links to other Symmetrix units, only one port from each processor can be used.

Disk Director The Symmetrix 5330/3330 disk directors manage the interface to the physical disk devices (HDAs), and are responsible for data movement between the HDAs and cache. The HDAs are connected to disk directors through industry-standard SCSI interfaces with two advanced microprocessors per disk director.

The Symmetrix 5330/3330 contains two disk directors. Each director, with its two advanced microprocessors, supports up to sixteen 18 GB or 9 GB 3.5-inch disk devices — one to four disk devices per SCSI bus. (See Figure 5.)


The Symmetrix 5330/3330 supports the following:

Each disk director provides an alternate path to the disk devices of its dual-initiator disk director pair. That is, should the primary path through a disk director to a disk device fail, Symmetrix accesses that device through the other disk director in the pair via its dual-initiator function. Refer to Dual-Initiator Feature on page 124 for more information on this data availability feature.

Cache Memory is one of the most crucial components of a Symmetrix system. All read and write operations transfer data to or from cache. Any transfers between the host processor, channel directors and cache are achieved at much greater electronic speeds than transfers involving disks. Symmetrix optimizes data movement between disk and cache, resulting in the highest performance possible.

Each cache memory card has two cache buses, x and y, with each having a 250 MB bandwidth for a total processing bandwidth of 500 MB per second. The Symmetrix 5330/3330 has two slots dedicated to cache memory. The subsystem supports a maximum of 8,192 MB of cache. Individual cache memory cards are available in 512 MB, and 1 GB, 2 GB, and 4 GB sizes.

Model 5330/3330

Number of Disk Directors 2

Maximum Number of Disk Devices 32

Number of Buses per Disk Director 4

Minimum Number of Disk Devices per Bus 1

Maximum Number of Disk Devices per Bus 4

Maximum Number of Disk Devices per Director

16

Maximum Number of Logical Volumes per Dual-initiator Pair

1,024


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2.5 Channel AttachmentsSymmetrix can attach to all parallel channels (5330 only), all ESCON channels, all Fibre Channels, all Fast-Wide SCSI or Ultra SCSI channels, or a mix of channel types. The physical connection to a Symmetrix parallel channel interface occurs at the Bus and Tag connector panel. The physical connection to a Symmetrix serial, Fast-Wide or Ultra-SCSI, or Fibre Channel interface occurs at the connectors on the channel adapters.

The Symmetrix Enterprise Storage Platform option is required when both mainframe hosts (parallel and ESCON channels) and open systems hosts (Fast-Wide SCSI channels or Fibre Channels) connect to the same Symmetrix system. Refer to the Symmetrix Enterprise Storage Platform Product Guide and the Symmetrix Open Systems Environment Product Guide for more information.

Parallel Channel Interface Connections

(5330) Parallel channels use two cables: the Bus cable contains the signal lines for transporting data to and from the host system; and the Tag cable controls data traffic on the Bus cable.

The Symmetrix 5330 supports two parallel channel directors. Each parallel channel director provides four physical interfaces for communicating with the parallel channels in the host system (Processor a, ports A and B; Processor b, ports A and B). The Symmetrix 5330 can have two parallel channel directors for a maximum of 8 parallel host interface connections.

The Bus and Tag cables attach to a Symmetrix parallel channel interface as shown in Figure 8. The maximum cable length between the host processor

Channel Attachments 65

and the parallel channel interface is 400 feet (122 m). This includes 15 feet for every control unit on the channel.

Figure 8. Parallel Channel Attachment

Symmetrix parallel channel interfaces can also connect to ESCON channels via ESCON converters. Each ESCON channel connects directly to one of the parallel host interfaces on the Symmetrix channel director. The maximum data transfer rate in this configuration is 4.5 MB/sec. ESCON channels utilized in this manner operate as type FX or CNV and use a 9034-type converter unit.

When an ESCON converter is used to attach ESCON channels to the Symmetrix parallel channel interface, Bus and Tag cables are used between the Symmetrix parallel channel interface and the ESCON converter and a fiber optic cable between the ESCON converter and the ESCON channel. Figure 9 illustrates this type of channel attachment. The maximum Bus and Tag cable length is 400 feet (122 m). The maximum fiber optic cable length is 3,937 feet (1.2 km) from an ESCON channel to an ESCON converter.

Figure 9. Parallel Channel Attachment to ESCON Channels


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Serial Channel Interface Connections

The Symmetrix 3330/5330 uses serial channel connections for the Symmetrix ESP software enabler option, which allows the Symmetrix 3330/5330 to transfer data between UNIX and mainframe DASD.

Serial channels use fiber optic cables. These serial channels are formally called the ESA/390 Enterprise Systems Connection Architecture (ESCON) I/O interface. The serial channels use point-to-point or switched point-to-point links. Each link has two physical fibers for transporting data: one for inbound signals and one for outbound signals. Today’s ESCON implementation supports data transfer rates up to 17 MB/sec.

There are two types of fiber optic cables: multimode and single-mode. Multimode cables support a maximum link length of 1.86 miles (3 km). Single-mode cables support a maximum link length of 14.3 miles (20 km) with the Extended Distance Feature (XDF). Symmetrix connects to multimode cables only.

The Symmetrix 5330/3330 supports two to four serial channel directors. Each serial channel director provides two or four physical interfaces for communicating with the serial channels in the host system, interfaces A and B.

In the ESCON environment, a link connects a host serial or ESCON channel with a Symmetrix serial channel interface. This link can be a direct connection between the processor or LPAR and the serial channel interface. This link can also have up to two ESCON Directors configured between the processor or LPAR and the serial channel interface. Symmetrix supports a maximum connection length of 26.7 miles (43 km) with two single-mode cables and one multimode cable.

Figure 10 illustrates several types of ESCON channel attachments.


Figure 10. ESCON Channel Attachment

Parallel and Serial Channel Extenders

This section describes the various types of conversion devices and channel extenders compatible with Symmetrix for channel attachment. Symmetrix can attach to both Block Mux (parallel) and ESCON (serial) channels directly or through conversion devices, channel extenders, or directors. Figure 11 illustrates these types of attachments.


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The channel type shown in Figure 11 uses the IOCP nomenclature:

• BL for Block Mux Channel• CNC for native ESCON• CVC for ESCON converter channel• ESCD for an ESCON Director

Figure 11. Possible Channel Attachments

ESCON-to-Parallel Converter. The IBM 9034 ESCON converter (or equivalent device) attaches an ESCON channel (Type=CVC) directly to a Symmetrix parallel channel via an ESCON director.

ESCON Director. The ESCON director provides dynamic switching and extended link path lengths (with XDF capability) when attaching an ESCON channel (TYPE=CNC) to a Symmetrix serial channel interface. One or two ESCON directors may be configured in the channel attachment. However, one of the directors must be configured with a static connection because the ESCON architecture recognizes only one port address. The dynamic switch configuration is defined in the IOCP. The ESCON director may also be used to provide additional flexibility and extend channel lengths when used with channel converters.


Channel Extender. The IBM 9036 Remote Channel Extender (or equivalent device) attaches an ESCON channel (TYPE=CNC) to a Symmetrix serial channel interface. It extends the distance of the connection and depending on the model can convert connections from multimode (3 km) to single mode (20 km). Connections to Symmetrix serial channel interfaces must be multimode.

Fast-Wide and Ultra-Fast-Wide SCSI Channel Attachments

The Symmetrix 5330/3330 attaches to most differential wide SCSI host channels.The physical connection to a Fast-Wide or Ultra-Fast Wide SCSI channel interface occurs at the connectors on the SCSI adapters located at the rear of the Symmetrix unit. Figure 12 illustrates two types of SCSI attachments.


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Figure 12. Fast-Wide and Ultra SCSI Attachments

For detailed information on Fast-Wide SCSI and Ultra-Fast-Wide SCSI channel attachments and cables, refer to the Symmetrix Open Systems Environment Product Guide and the Symmetrix High Availability Product Guide.

Fibre Channel Attachments

The Symmetrix Fibre Channel adapter provides an interface between the director and host channels. Each Fibre Channel adapter is located at the rear of the backplane, opposite its corresponding channel director. These adapters provide the connectivity between the host channels and the Fibre Channel directors (FC-0 layer of the Fibre Channel standard). Each adapter provides transceiver connections for two Fibre Channel ports (four directors, eight Fibre Channel ports).

DIFFERENTIALWIDE

SCSI HOST

FAST-WIDESCSI

DIRECTOR

ULTRA FAST-WIDESCSI

DIRECTOR

DIFFERENTIALWIDE

SCSI HOST


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Chapter 3 SYMMETRIX
INPUT/OUTPUT OPERATIONS

This chapter describes input/output operations between the Symmetrix 3330/5330 ICDA and a host system.

• ICDA Operation ........................................................................................ 74• Elements of a Symmetrix I/O Operation .............................................. 79• Dynamic Path Reconnection (Mainframe Systems)............................. 87

73

3.1 ICDA OperationIntelligent cache configurations allow Symmetrix systems to transfer data at electronic memory speeds that are much faster than physical disk speeds. Integrated Cached Disk Array (ICDA) operation in Symmetrix systems is based on the principle that the working set of data at any given time is relatively small when compared to the total subsystem storage capacity. When this working set of data is in cache, there is a significant improvement in performance. The success of an ICDA subsystem is based upon satisfaction of the following two characteristics:

Locality of Reference. If a given piece of information is used, there is a high probability that a nearby piece of information will be used shortly thereafter.

Data Reuse. If a given piece of information is used, there is a high probability that it will be reused shortly thereafter.

This cache principle has been in use for years on host systems (CPU and storage devices). Figure 13 illustrates this type of host cache use. The cache used in this manner is often a high speed, high cost storage unit used as an intermediary between the CPU and main storage.

.

Figure 13. Host Cache Use

74 SYMMETRIX INPUT/OUTPUT OPERATIONS

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Symmetrix Cache Management

Symmetrix uses the same cache principle as host systems, but with enhanced caching techniques. Figure 14 illustrates cache use in Symmetrix.

Figure 14. Symmetrix Cache Management and Data Flow

In Symmetrix, the channel directors and disk directors share cache. Symmetrix channel directors attach to the CPU channels as well as to cache. Symmetrix disk directors attach to cache as well as the disk drives. The Symmetrix directors perform the following functions:

• The channel director handles I/O requests from the host. It accesses the directory in cache (Figure 14) to determine if the request can be satisfied within the cache. The directory contains information on each cache page and blocks within each page.

• The channel director manages cache using an Age Link Chain table and Least Recently Used (LRU) algorithm. An Age Link table maintains the references to the Most Recently Used (MRU) to Least Recently Used page locations. The LRU

Symmetrix 3000 and 5000 ICDA

Channel Director

Cache Memory

Disk Director Disk

Directory

Host System

ICDA Operation 75

algorithms use the information in this table to ensure that only pages of data that have been used recently are kept in cache.

• Using the Prefetch Algorithm, the disk director dynamically detects sequential data access patterns to the disk devices. The directors improve the hit ratio of these accesses by promoting blocks from the disk devices to cache slots before that data has been requested. The prefetch algorithm can stage two to 12 tracks to cache depending on access patterns.

• The disk director manages access to the disk drives. When a "read miss" occurs, the disk director also stages tracks into cache. It also performs a background operation that destages “written-to” blocks to disk.

LRU Algorithm Figure 15 illustrates data flow with the LRU algorithm. Each time a read hit or write hit occurs, Symmetrix marks that cache slot as most recently used and promotes it to the top of the LRU list. For each write, a written-to flag is set on the initial write to each cache block and is cleared when the cache block is destaged. At the bottom of the LRU list is the least recently used cache slot.

Prefetch Algorithm Symmetrix systems continually monitor I/O activity and look for access patterns. When the second sequential I/O to a track occurs, the sequential prefetch process is invoked and the next track of data is read into cache. The intent of this process is to avoid a read miss.


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Figure 15. LRU and Age Link Chain Data Flow
This process of using the tracks in an alternating fashion prevents cache pollution caused by conventional sequential caching algorithms. Should a read miss occur, the Symmetrix system will increase the number of track slots from two to five. If a read miss still occurs, the Symmetrix prefetch routines will increase the slots to eight. The maximum number of track slots that will be allocated for sequential operation is 12. Should I/O activity reduce, the number of track slots will be reduced accordingly. When the host processor returns to a random I/O pattern, the Symmetrix system will discontinue the sequential process.

ICDA Operation 77

Symmetrix I/O Performance Enhancements

Symmetrix uses these techniques to enhance its I/O performance:

• Split Director Functions - The director operations are split into two functional parts, the channel director and disk director. The channel director services requests from the host. The disk director services requests between cache and disk. Splitting the director functions eliminates the processing overhead and cache locking associated with Control Units that perform both functions.

• High Speed Cache Memory - Cache memory speed is greater than the total speed of all components (e.g., the directors) that access it.

• Disk Microprocessor and Buffer - Each disk device has its own microprocessor and buffer. This intelligence is brought to the actuator level providing parallel processing of data. These features add another level of caching and improve overall performance.

• Multiple Disk Directors - A maximum of 16 disks attach to each Symmetrix 3330/5330 disk director. For more information on director and disk combinations, refer to Disk Director on page 63.

• Sequential Access Patterns - Access patterns can be sequential, random, or a combination of both. When a miss occurs on a sequential access pattern, the number of blocks brought into cache is increased, thus improving the hit rate (requested data is in cache).


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3.2 Elements of a Symmetrix I/O Operation

All I/O operations require a certain response time. An I/O request begins with the application issuing an I/O command and ends when the transfer completes. The time lapse from I/O request to transfer completion is the I/O response time.

I/O Response Time - Mainframe Environment

In the mainframe environment, I/O response time can be divided into a queuing time, a pend time, a connect time, and a disconnect time, as shown in Figure 16.

Figure 16. I/O Response Time (Mainframe Environment)

The Queuing Time is the I/O Supervisor (IOS) queue for next event

The Pend Time consists of:

• Control Unit Busy (CUB)• Device Busy (DB)• Director Port Busy

The Connect Time is the length of time the channel is processing commands and transferring data.

Elements of a Symmetrix I/O Operation 79

The Disconnect Time is:

• The length of time it takes to retrieve data from the physical disk (device seek and latency)

• The length of time it takes to reconnect to the host

• SRDF write overhead (protocol, line latency, etc.)

I/O Response Time - Open Systems Environment

In the open systems environment, I/O response time can be divided into a host queuing time, a command connect time, a disconnect time, and a data connect time, as shown in Figure 17.

Figure 17. I/O Response Time (Open Systems Environment)

The Host Queuing Time is the time the request is in the host queue before it is dispatched on the SCSI bus.

The Command Connect Time is the length of time the channel is transferring a SCSI command.

The Disconnect Time is the length of time involving device seek and latency. At this time the SCSI bus can be used by other devices.

In case of a cache hit in an I/O request, the Disconnect Time requirement is eliminated.

The Data Connect Time is the length of time the channel is transferring data.


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Symmetrix I/O Operations

There are four basic types of Symmetrix I/O operations (Figure 18):

• Read Hit• Read Miss• Fast Write• Delayed Fast Write

Figure 18. Types of Symmetrix I/O Operations


Symmetrix performs read operations from cache. Symmetrix always caches write operations. This cache operation is transparent to the host operating system. A read operation causes the channel director to scan the cache directory for the requested data. If the requested data is in cache, the channel director transfers this data immediately to the channel with a channel end and device end (or a SCSI good ending status). If the requested data is not in cache, the disk director transfers the data from the disk device to the cache and the channel director transfers the requested data from the cache to the channel.

Destaging Operation

In addition to the four types of I/O operations mentioned, Symmetrix performs a background operation that destages blocks back to disk. This allows any written-to or changed data to be maintained in two locations: cache for performance in the occurrence of reuse of that data, and on disk to maintain the highest levels of data integrity. Any pending writes are assured of arrival to the intended disk even in the event of power failure. Figure 19 illustrates this destaging operation.

Figure 19. Destaging Operation


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Read Operations

There are two types of read operations: read hit and read miss. Figure 20 illustrates the data flow for read operations.

Figure 20. Read Operations

Read Hit In a Read Hit operation (Figure 20), the requested data resides in cache. The channel director transfers the requested data through the channel interface to the host and updates the cache directory. Since the data is in cache, there are no mechanical delays due to seek, latency, and Rotational Position Sensing (RPS) miss (Figure 21).

For more information on RPS, refer to Disk Devices on page 51.


Figure 21. Read Hit

Read Miss In a Read Miss operation (Figure 22), the requested data is not in cache and must be retrieved from a disk device. While the channel director creates space in the cache, the disk director reads the data from the disk device. The disk director stores the data in cache and updates the directory table. The channel director then reconnects with the host and transfers the data. If the requested data is in the process of being prefetched (sequential read ahead), the miss is considered to be a "short miss." If the requested data is not in the process of being read into cache, the disk director requests the data from the drive. This miss is considered to be a "long miss."

Since the data is not in cache, Symmetrix must search for the data on disk and then transfer it to the channel. This adds seek and latency times to the operation (Figure 22). During the disconnect time, other commands can be executed on other devices on the bus, or, commands can queue to the same device.

Figure 22. Read Miss


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Write Operations

Symmetrix write operations occur as either Fast Write or Delayed Fast Write operations (Figure 18 on page 81).

Fast Write A Fast Write occurs when the percentage of modified data in cache is less than the Fast Write threshold. On a host write command, the channel director places the incoming block(s) directly into cache.

For fast write operations, the channel director stores the data in cache and sends a channel end and device end (or a good ending status) to the host computer. The disk director then asynchronously destages the data from cache to the disk device.

Figure 23. Write Operations


Since Symmetrix writes the data directly to cache and not to disk, there are no mechanical delays due to seek, latency, and Rotational Position Sensing (RPS) miss (Figure 24).

Figure 24. Fast Write

Delayed Fast Write A Delayed Fast Write occurs only when the Fast Write threshold has been exceeded. That is, the percentage of cache containing modified data is higher than the Fast Write threshold. (The default cache write ceiling is 80% of the cache).

Figure 25. Delayed Fast Write

If this situation occurs, Symmetrix disconnects the channel directors from the channels. The disk directors then destage the Least Recently Used data to disk. When sufficient cache space is available, the channel directors reconnect to their channels and process the host I/O request as a Fast Write (Figure 25). Symmetrix continues to process read operations during delayed fast writes. With sufficient cache present, this type of cache operation will rarely occur.


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3.3 Dynamic Path Reconnection (Mainframe Systems)

Dynamic Path Reconnection (DPR) in conventional mainframe DASD permits the host to disconnect from the Storage Control Unit (SCU) while it locates a record to do another operation. When the SCU finds the data, the host can reconnect to the SCU on any available channel path between the device and the host system if the original channel is busy with other operations. Without the DPR function invoked, the SCU waits for the original channel path to become available again, and the correct data to be located under the disk’s head, before continuing the operation. Refer to the IBM 3390 Direct Access Storage Introduction or IBM 3380 Direct Access Storage Introduction for more information on this function.

The DPR option must be invoked in an ESCON environment in order to facilitate reduction of director port busy conditions. DPR must also be enabled when using extended platform functions, such as IBM’s Concurrent Copy.

DPR support is enabled by the EMC Customer Engineer at installation or service. Consult your EMC Systems Engineer to determine if DPR is right for your operating environment.

Dynamic Path Reconnection (Mainframe Systems) 87

4

Chapter 4 GETTING THE BEST PERFORMANCE

This chapter describes the performance features of the Symmetrix 3330/5330 ICDA.

• Performance Features ................................................................................ 90• Open Systems Hyper-Volumes ................................................................ 95• Mainframe System Hyper-Volumes ...................................................... 101• Optimizing Performance for Open Systems Devices.......................... 107• Performance Guidelines for Mainframe Devices ................................ 109• Monitoring Symmetrix Performance in a Mainframe Environment 112• Multi-Port Volume Access for Open Systems Environments ............ 115

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4.1 Performance FeaturesSymmetrix offers improved performance over conventional Storage Control Units and DASD designs. The Symmetrix features described below allow high cache hit ratios and less processing overhead, reducing response time and improving throughput.

Cache A cache size of up to 8,192 MB and intelligent caching algorithms greatly improve hit ratios and overall subsystem response time. Symmetrix caches all read and write operations making them transparent to the host operating system.

Symmetrix proprietary caching algorithms search quickly and efficiently to determine whether the requested data is in cache. They also understand how the application is accessing the data and tune themselves accordingly in real time. The cache management algorithms respond to channel requests to manage the cache via host processor software when appropriate and perform the management functions independently when the host processor does not make requests.

Fast Write Capabilities

Symmetrix caches write operations, eliminating the need to write data to the disk immediately. This results in faster response times and improved overall subsystem performance. The write ceiling is 80% of the usable cache. Channel directors and disk directors dynamically allocate cache space between reads and writes depending on I/O activity.

90 GETTING THE BEST PERFORMANCE

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Multiple Channel Directors

Symmetrix contains multiple channel directors, each supplying an independent path to cache or disk from the host system. The Symmetrix 3330/5330 systems have two to four channel directors.

Symmetrix 3330 systems support connectivity to open UNIX, Windows NT and AS/400 systems through Fast-Wide SCSI, Ultra-Fast-Wide SCSI and Fibre Channel interfaces. When optional ESP (Enterprise Storage Platform) software is added, the Symmetrix 3330 systems can simultaneously support mainframe system connections through ESCON channels.

Symmetrix 5330 systems support connectivity to mainframe systems through ESCON or block multiplexer parallel channels. When optional ESP (Enterprise Storage Platform) software is added, the Symmetrix 5330 systems can simultaneously support open UNIX, Windows NT and AS/400 systems through Fast-Wide-Differential (FWD) SCSI, Ultra-SCSI, and Fibre Channel interfaces.

For detailed information on each of the following Symmetrix channel directors, refer to Channel Director Descriptions on page 59:

• Serial Channel Directors• Parallel Channel Directors (5330 systems only)• Fast-Wide-Differential SCSI Channel Directors• Ultra-SCSI Channel Directors• Fibre Channel Directors• Remote Link Channel Directors (used with SRDF

and SDMS)

Parallel Processing

Each channel director and disk director has two resident microprocessors, and each disk device has one resident microprocessor. These microprocessors make use of advances in parallel processing to reduce processing time and improve throughput.

Performance Features 91

Dynamic Mirror Service Policy

The Symmetrix Dynamic Mirror Service Policy (DMSP) is an enhancement to the adaptive algorithms in the Symmetrix architecture that improves the performance of read operations in mirrored environments. The improved system performance is a result of Symmetrix balancing the load between physical disk drives, disk directors and minimizing actuator movement.

To achieve this improved performance, Symmetrix measures and tracks I/O activities of logical volumes, physical volumes and disk directors. Then, based on these measurements, Symmetrix directs read operations for mirrored data to the appropriate mirror that results in the best overall performance of the Symmetrix. As the access patterns and workloads change, the dynamic algorithm analyzes the new workloads and adjusts the service polices as needed.

RPS Miss Elimination

In Symmetrix, each disk device has a dedicated microprocessor and segmented data buffer that can temporarily store data until the disk director is ready to read or write data. This eliminates rotational position sensing (RPS) misses that occur in conventional DASD when the heads are positioned over the desired sector, but the channel path is not ready for read or write operations. The segmented data buffer of the disk device allows multiple operations to occur to the head/disk assemblies.

Channel Speeds

Symmetrix Fast-Wide SCSI channels transfer data at speeds up to 20 MB/sec. The data transfer rate is host dependent. Symmetrix supports cable lengths of up to 82 feet (25 m) to attach to most host systems.

Symmetrix Ultra-SCSI channels transfer data at speeds up to 40 MB/sec. On each Ultra-SCSI channel


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director, data transfers from the host to cache occur as four concurrent operations. Symmetrix supports cable lengths of up to 62 feet (19 meters) in length.

Fibre Channels transfer data at speeds up to 100 MB/sec. Symmetrix supports cable lengths from 16 feet (5 meters) to up to 1,640 feet (500 meters).

For information on SCSI host adapters and cable requirements for your Symmetrix 3330/5330, consult your EMC sales representative.

Symmetrix serial channels transfer data at speeds up to 17 MB/sec. The data transfer rate is host dependent. Symmetrix supports serial fiber cable connections to 26.7 miles (43 km).

(5330) Symmetrix parallel channels (Symmetrix 5330 systems only) transfer data at speeds of 1.0 to 1.5 MB/sec., 3.0 MB/sec., and 4.5 MB/sec. Each parallel channel director is configured independently and each channel interface can operate at different speeds simultaneously.

PermaCache Option

Symmetrix allows you to permanently assign mission-critical data requiring very high performance to cache. A variable number of contiguous cylinders on the disk devices can be reserved for PermaCache backup.

PermaCache is best used for infrequently accessed data that needs instantaneous response, since this data is normally not in cache at the time it is requested. The Symmetrix large cache and intelligent caching algorithms strive to keep frequently accessed data in cache making its assignment to PermaCache unnecessary.

Other Symmetrix options that require cache area affect the amount of cache memory available for

Performance Features 93

PermaCache. For example, enabling the RAID-S option may require adjustment of memory assignments by reducing the existing PermaCache area, lowering the write pending ceiling of the system, or reducing the number of Symmetrix RAID groups defined.

You must have more than the minimum (base) amount of memory for your configuration to use part of it as PermaCache. To determine the minimum amount of memory for your Symmetrix configuration consult your EMC sales representative. Base cache amounts for Symmetrix 3330/5330 systems are defined in Tables 25 through 29 starting on page 187.

Should a power failure occur, records that have been updated in PermaCache will be destaged to disk. Should a cache memory board require online replacement, PermaCache is unaffected provided that the replacement contains the same amount of cache. Replacement with a smaller capacity cache requires that the system be brought offline and reinitialized before PermaCache will function.


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4.2 Open Systems Hyper-Volumes For use of this feature in Symmetrix units connected to mainframe hosts, refer to Mainframe System Hyper-Volumes on page 101.

The Hyper-Volume Extension feature provides configuration flexibility by allowing one physical device to be split into multiple logical volumes. This capability is particularly useful for some 32-bit implementations of UNIX that allow only 2 GB file systems per single logical disk. For example, up to 8 2 GB logical disk volumes can be defined for a single Symmetrix 18 GB disk device.

The Symmetrix 3330-18 and 5330-18 use 3.5-inch, 18 GB disk devices. The 18 GB disk device provides a maximum of 36,830 Symmetrix cylinders.

The Symmetrix 3330-9 and 5330-9 use 3.5-inch, 9 GB disk devices. The disk device provides a maximum of 18,414 Symmetrix cylinders.

For the maximum number of cylinders per logical volume for both device sizes, refer to Table 14 on page 97.

For Symmetrix 3330 disk devices attached to UNIX or PC server hosts, each cylinder has 15 tracks and each track contains sixty-four 512-byte blocks.

If you are attaching Symmetrix 3330-9 3.5-inch 9 GB disk devices exclusively to AS/400 host(s) or attaching the disk devices to a mixture of AS/400 and UNIX hosts, the logical volume structure is slightly different resulting in fewer cyl-inders per disk device. Symmetrix 3330 9 GB disk devices can be split into a maximum of 2 usable hyper volumes when used in an AS/400 environment. For information on the maximum number of cylinders per logical volume in an AS/400 environment, refer to the AS/400 chapter of the Symmetrix Open Systems Environment Guide or consult your EMC sales representative.

Open Systems Hyper-Volumes 95

Split-Volume Capability

When splitting a single physical device into multiple logical volumes, Symmetrix allows up to 32 logical volumes to reside on one physical volume with the following considerations:

• Configuration requirements for Symmetrix systems vary according to the applications used. To configure logical volumes for optimum Symmetrix performance, consult your EMC Systems Engineer.

• On the Symmetrix 3330-9 and 5330-9, although up to 32 logical volumes can reside on a single Symmetrix 9 GB physical disk device, this large number of logical volumes on a single device is usually not necessary or recommended.

• To utilize full disk capacity, the Symmetrix 18 GB disk devices should be configured with at least 2 logical volumes in the sizes shown in Table 14 on page 97.

Table 14 shows the number of ylinders available per logical volume in 9 GB and 18 GB physical disk devices. It also lists the formatted capacity of each volume.


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Table 14. Cylinders per Logical Volume for Split Physical Devices a b c d

Disk Size1 Logical

Volume per Disk Device

2 Logical Volumes per Disk Device



9 GB (3.5")18,414 Cylinders

8.42 GB2 (9.05 GB10)

9,206 Cylinders4.21 GB2

(4.52 GB10)


(3.01 GB10)


(2.26 GB10)

18 GB (3.5")c 18,414 Cylinders

8.42 GB29.05 GB10

12,275 Cylinders5.61 GB26.03 GB10

9,206 Cylinders4.21 GB24.52 GB10






3.37 GB23.62 GB10









1.87 GB22.01 GB10









1.29 GB21.39 GB10




a. Individual hosts might require specific cylinder counts for their filesystems. Refer to the section for your specific host in the Symmetrix Open Systems Environment Product Guide to determine its cylinder requirements.

b. The GB2 value is based on the convention: 1 GB = 1024x1024x1024 bytes.

The GB10 value is based on the convention: 1 GB = 1000x1000x1000 bytes.

Although these values are expressed differently, their values are equivalent.

c. To utilize full disk capacity, the 18 GB disk devices should be configured with at least 2 logical volumes in the sizes shown in the table above. However, if the maximum logical device size is required, split the 18 GB devices into two logical volumes of the following cylinder sizes: 32,510/4,318.

d. The cylinder counts shown here are for Symmetrix units attached to UNIX and/or PC hosts only. These cylinder counts are different for Symmetrix 3330/5330 units attached to AS/400 hosts or both AS/400 and UNIX hosts.

Logical Volume Mapping

Symmetrix supports up to 1,024 logical volumes (address range 000 to 3FF) per unit. The logical-to-physical relationship chosen can automatically apply to all devices in the unit. It is also possible to customize the logical-to-physical relationship on each device as well as the size of each logical volume.

For example, if the logical-to-physical ratio chosen is 3:1, the logical volume mapping that occurs appears similar to that shown in Figure 26.

Although a Symmetrix system can support up to 1,024 logical volumes, the allocation per SCSI director is limited to 960 logical volumes.

Figure 26. 3:1 Logical Volume Mapping

In another example, if the logical-to-physical relationship is 2:1. The logical volume mapping appears similar to that shown in Figure 27.

Figure 27. 2:1 Logical Volume Mapping


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Meta Volume Addressing

Several operating systems, such as Windows NT and some open systems environments, require larger volumes than are provided by standard Symmetrix physical disk devices. By allowing individual physical disk devices to be grouped together into a Meta Device and the capability of meta volume addressing, Symmetrix enhances disk system functionality in these environments. To increase throughput and further improve performance, Symmetrix provides multiple I/O drive queues for Meta Devices.

Symmetrix Meta Devices must consist of adjacent Symmetrix devices. Symmetrix allows the concatenation of contiguous logical devices, up to 512 GBs per Meta Device.

Meta Volume Data Striping

Symmetrix allows data to be striped across the multiple drives of a Meta Device. Striping data across the multiple drives in definable cylinder stripes was designed to benefit “random reads” by avoiding stacking multiple reads to a single spindle and disk director. The striped Meta Devices use equal size stripes of data from each participating drive in an interleaving manner. This scheme creates a large device, but additionally balances the I/O activity between the disk devices and the Symmetrix disk directors. Table 15 defines the data stripe sizes and capacities for Symmetrix Meta Devices.

Table 15. Meta Volume Stripe Sizes

Stripe Size Stripe Capacity (KB)

2 Cylinders 960

4 Cylinders 1,920

8 Cylinders 3,840


16 Cylinders 7,680

32 Cylinders 15,360

64 Cylinders 30,720

Table 15. Meta Volume Stripe Sizes

Stripe Size Stripe Capacity (KB)


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4.3 Mainframe System Hyper-Volumes

For use of this feature in Symmetrix units connected to Open System hosts, refer to Open Systems Hyper-Volumes on page 95.

Symmetrix enhances disk system functionality by supporting multiple logical volumes on each physical disk device. The Hyper-Volume Extension feature has two usage options:

• Split-volume Capability

• Allows up to eight logical volumes on each Symmetrix 3330-9 or 5330-9 physical device

On the Symmetrix 3330-9 and 5330-9, although Symmetrix microcode allows up to 32 logical volumes to reside on a single 9 GB physical disk device, this large number of logical volumes on a single device is usually not necessary or recommended.

• Allows up to 32 logical volumes on each Symmetrix 3330-18 or 5330-18 physical disk device

Configuration requirements for Symmetrix systems vary according to the applications used. To configure logical volumes for optimum Symmetrix performance, consult your EMC Systems Engineer.

• Extended Cylinder Addressing - establishes a small logical volume at the end of physical disk device for data requiring high performance on a small volume.

The following sections explain the cylinders available for various drive emulation types, and how

Mainframe System Hyper-Volumes 101

to calculate the available cylinders for the Extended Cylinder Addressing and the Split-volume features.

Split-Volume Capability

Using the Split-Volume option of the Hyper-Volume Extension feature, Symmetrix allows multiple logical volumes to reside on a single physical drive. For example, a single 18 GB drive could support up to six logical 3390-3s, or up to 18 logical 3390-1s, or four logical 3390-3s and six logical 3390-1s. This provides for the consolidation of many physical DASD devices into far fewer physical high-capacity high-performance disks. Support is provided for native IBM 3390 and 3380 track emulation with all 3390 and 3380 disk volumes being supported. No modifications are required to the operating system, application, or program software to take advantage of HVE.

The Symmetrix 3330/5330 supports up to 1,024 logical volumes (address range 000 to 3FF) per unit. The Split-Volume option can override the normal one-to-one logical-to-physical relationship on all devices in the Symmetrix unit.

The logical-to-physical relationship can automatically apply to all devices in the unit. It is also possible to customize the logical-to-physical relationship on each device as well as the size of each logical volume.

Extended Cylinder Addressing Option

Extended Cylinder Addressing places a small logical volume at the end of a disk device. Each small logical volume can occupy a variable number of contiguous cylinders. This small logical volume can be as small as one cylinder in size. The maximum number of cylinders for this volume depends on the capacity of the disk device and the emulation mode selected.

This logical volume configuration flexibility increases system performance. For example, it allows


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you to have four volumes on a 9-GB disk device, three volumes emulating a full 3390-3 device and one small volume for datasets requiring extremely high performance such as Multi-Image Manager files, JES Checkpoint, RACF Control files, or catalogs.

Because the data of interest resides on a small volume, the Unit Control Block (UCB) busy conditions that arise when this data is placed on larger capacity volumes with high activity are eliminated. This reduces IOSQ exposure and increases system performance.

Consult your EMC Systems Engineer regarding dataset placement on these small logical volumes.

This logical volume can be added to already running Symmetrix units without affecting existing data on the disk device by giving the volume an address beyond any currently used on the unit.

This option may also be used with the PermaCache option, in which infrequently accessed datasets requiring instantaneous access reside permanently in cache.

Determining Cylinders for Hyper-Volume Data

Before you can use either Hyper-Volume Extension option, the split-volume option or extended cylinder addressing, you must determine the Total User Cylinders on the physical disk device available for user data.

The number of cylinders available for user data depends on the:

• Symmetrix disk device cylinder capacity• Selected disk emulation type • Alternate, Diagnostic, and Device Support

(ADDS) cylinders for the emulation type• Desired number of logical volumes for the


Symmetrix disk device

Table 16 lists the Symmetrix 18 GB and 9 GB disk device capacities for 3380 and 3390 emulations.

Table 17 outlines the cylinders required for full emulation per logical volume for several emulation types. It also lists the number of alternate, diagnostic, and device support cylinders (ADDS) required for each logical volume by that particular emulation type.

Calculate UserCylinders -

Example

In this example, you will calculate user cylinders for an 18 GB disk device emulating a 3390-3 device. With 21,060 cylinders available for 7 logical volumes, you

Table 16. Available Cylinders for 18 GB and 9 GB Emulated Disk Devices

Available Symmetrix Cylinders

Drive Size 3380 Emulation 3390 Emulation

18 GB (3.5") 24,350 21,060

9 GB (3.5") 12,186 10,537

Table 17. Device Emulations and

Emulation Type Number of CylindersAlt, Diag, Device Support

Cylinders (ADDS)

3380D 885 3

3380E 1,770 4

3380K 2,655 5

3380K(+) 3,339 5

3380K(++) 3,993 5

3390-1 1,113 4

3390-2 2,226 4

3390-3 3,339 4

3390-9 10,017 7


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would have 6 fully emulated 3390-3 volumes and one small volume. First determine the number of User Cylinders with the following formula, then calculate the number of the extra cylinders available for the small volume.

User Cylinders = Available Symmetrix cylinders (21,060, Table 16) minus [desired number of logical volumes on the physical device multiplied by the ADDS for desired emulation type (Table 17)]

For example, the Symmetrix 18 GB disk device, when emulating six 3390-3 logical volumes and 1 small logical volume, has 21,032 User Cylinders available for the 7 logical volumes. The formula works as follows:

User Cylinders = 21,060 - (7*4) = 21,032

Calculate FullEmulation

Volumes and ExtraCylinders

Using the number of User Cylinders just calculated (21,032), you can determine the number of full emulation volumes and number of extra cylinders that the disk device can accommodate by using this formula:

User Cylinders - [emulation type’s total cylinders (from Table 17) * number of fully emulated logical volumes]

As an example, the 21,032 User Cylinders on the 18 GB disk can accommodate 6 full 3390-3 logical volumes and 998 extra cylinders for the seventh as follows:


1. Calculate the number of cylinders on 6 full 3390-3 logical volumes:

Number of cylinders for each emulated device (3,339) * 6 = 20,034

2. Determine the number of extra cylinders for the seventh volume by subtracting the value in the above calculation (20,034) from the User Cylinders (21,032):

21,032 - 20,034 = 998 Cylinders


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4.4 Optimizing Performance for Open Systems Devices

Achieving optimal performance requires careful and detailed planning of the Symmetrix configuration according to the requirements of the host(s) you are connecting to Symmetrix and your performance needs.

Carefully review the issues listed below with your EMC representative before the EMC Customer Engineer installs the Symmetrix system. Planning and Installation on page 209 includes sample worksheets and checklists to assist you in this process.

• When configuring multiple hosts to a Symmetrix unit, distribute workloads by ranking the busiest to the least busy.

• Data storage capacity required for each host con-nected to Symmetrix.

• Number of channels available from each host.

• The nature of the applications executed on the host connected to Symmetrix.

• The availability of a Logical Volume Manager (LVM) on the host and the use of data striping.

• The use of hyper-volumes on Symmetrix, hyper-volume size, and the allocation of hyper-volumes between different hosts, different channels, and different applications.

• Maximum drive and filesystem sizes supported by each host connected to Symmetrix.

• Any requirements for device sharing.

Optimizing Performance for Open Systems Devices 107

• Number of Fast-Wide SCSI channel directors used and the number of ports used on each director.

• Host-level mirroring special considerations for device distribution in Symmetrix.

• The possibility of upgrading Symmetrix with additional drives in the future and its effect on the configuration if the model installed is not at maximum capacity.


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4.5 Performance Guidelines for Mainframe Devices

This section discusses the criteria you need to evaluate to match Symmetrix to your mainframe data storage needs.

Identifying Requirements

When choosing a data storage system, you need to match the needs of your data to the device. This involves identifying the type of data you will store on this device, and the performance and capacity required by the data.

Data AccessPatterns

For most transaction processing environments, data accesses often exhibit patterns that can be broken down into high, medium, and low activity, as shown in Figure 28.

Figure 28. Data Access Activity

In general, data requiring high activity is a small percentage of the total data accesses. For most users, several files meet this criteria. These files are often

Performance Guidelines for Mainframe Devices 109

referred to as “hot files.” In addition, most users have several files that have “hot spots,” portions of files that have high I/O activity.

Data activity or the access patterns can be constant, clustered, or time-dependent. Examples of these access patterns are:

• Constant: I/O activity for a dataset is low, medium, or high and doesn't fluctuate. Examples are: paging, temporary storage, and JES2 (MVS)

• Clustered: I/O activity varies to portions of a dataset or by the time of day. Examples are: database indexes at peak periods

• Time-dependent: I/O activity to a dataset varies over time. Examples are: nightly batch or month end jobs

Choosing Storage Devices

Once you identify the performance and capacity requirements of your data and the data access patterns, you can choose a storage device appropriate for your needs. Figure 29 shows a hierarchy of storage device types available today and the I/O activity they best serve.

Figure 29. Storage Hierarchy


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Symmetrix, with its large cache memory and disk storage capacity, services high, medium, and low activity data over a range of data access patterns. Symmetrix places data in the appropriate storage medium to maintain the necessary performance. The least-recently-used (LRU) algorithm automatically places frequently used data in cache and demotes infrequently used data to disk. This storage control function eliminates the need for you to physically transfer data from one storage medium to another to meet your capacity or performance requirements.

Performance Guidelines for Mainframe Devices 111

4.6 Monitoring Symmetrix Performance in a Mainframe Environment

To determine whether Symmetrix is providing the performance required, periodically monitor and evaluate actual performance using the I/O activity reports and the cache statistics. Symmetrix provides volume level cache statistics and is compatible with IBM and third party cache measurement software.

Setting Performance Objectives

The I/O response time and throughput requirement of the application data determine the performance requirements for Symmetrix. You can measure the performance capability of Symmetrix through the I/O response time and the accesses per second.

Work with your application programmers to select appropriate I/O response time targets for their application data.

Using RMF By running Resource Measurement Facility (RMF) reports during peak processing periods, you can effectively evaluate the performance of Symmetrix. Collect RMF data at selected 10- to 15-minute intervals during these peak periods. Refer to the RMF Reference and User’s Guide for information on how to run RMF reports.

You will find the following RMF Monitor 1 reports the most useful:

• Summary Report - Gives the processor-busy time, average response time, and average I/O rate. This report can help you identify peak periods.


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• Direct Access Device Activity Report - Gives the average response time, service time, and device utilization for specific devices and strings.

• I/O Queuing Activity Report - Provides information on the I/O configuration and contention rate, queue lengths, and percentages when one or more I/O components were busy. The report is grouped by logical control unit.

Using VM/Monitor and VMPPF

By running VM/Monitor during peak processing periods, you can effectively evaluate the performance of Symmetrix. The default collection interval is 60 seconds.

Use the VM Performance Planning Facility (VMPPF) to analyze the data collected by the Monitor. Refer to VMPPF General Information for information on how to use this facility.

Using Cache RMF Reporter

The Cache RMF Reporter is an automatic data collection and batch reporting tool that may be used with Symmetrix to evaluate cache performance. It consists of a user exit to RMF and a Post Processor Report program.

Symmetrix will report its cache statistics to the Cache RMF Reporter ONLY when it is configured for the 3990-3 or 3990-6 emulation mode.

The Cache RMF Reporter obtains all Symmetrix counts and status at the end of each RMF interval, calculates the difference in the counters (from the previous interval), and writes these values and the status to the System Management Facilities (SMF) dataset as user records.

Monitoring Symmetrix Performance in a Mainframe Environment 113

The Post Processor Report program reads the SMF user records, computes the cache statistics (i.e., hit ratios and read-to-write ratios), and produces detailed or summary reports by the RMF interval or by a specified daily duration. It can produce the Subsystem Summary Report only, or the following reports in detail:

• Device Counters Report• Device Aggregation Report• Subsystem Status Report• Subsystem Counters Report• Subsystem Aggregation Report• Subsystem Summary Report

Refer to the IBM Cache RMF Reporter Program Description/Operations Manual for information on how to use the Cache RMF Reporter and the various report types.


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4.7 Multi-Port Volume Access for Open Systems Environments

Unlike most disk arrays, the Symmetrix unit can present any logical volume through any number of SCSI channels to the hosts connected to the unit. Usually, a Symmetrix volume will be presented through one host channel. However, in different failover or cluster scenarios, the volume will be “visible” to different hosts on two or more SCSI channels.

For example:

• A volume may be configured to be visible on two channels for host channel failover (such as EMC PowerPath or HP-UX PV links).

• A volume can be accessed by up to 32 separate paths using EMC PowerPath.

• A volume may be configured to be visible on one channel for a hot standby scenario where one host can assume the devices of another host in case of a controller or host failure.

• A volume can be visible through all channels in cluster environments that can take advantage of such multi-port volume access (such as NCR Teradata).

For more information on multi-port volume access, refer to the Symmetrix High Availability Product Guide.

Multi-Port Volume Access for Open Systems Environments 115

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Chapter 5 MANAGING CRITICAL DATA

This chapter discusses the Symmetrix 3330/5330 features and options that affect data availability and reliability.

• Symmetrix Data Management Overview........ 118• Reliability and Availability Features................ 122• Data Integrity Protection ................................... 131• Data Protection Guidelines................................ 134• Mirroring.............................................................. 135• Symmetrix RAID-S ............................................. 138• Symmetrix Remote Data Facility ...................... 154• Dynamic Sparing ................................................ 155• Dynamic Sparing as Additional Protection .... 158

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5.1 Symmetrix Data Management Overview

Symmetrix has many features and options to ensure a high degree of system and data availability. Many of these features and options are built into the Symmetrix design. Other availability options may be purchased separately and implemented into the Symmetrix operation.

Symmetrix Reliability and Availability Features

The Symmetrix 3330/5330 design offers the following reliability and availability features:

• High reliability components• Redundant power subsystem• System battery backup• Dual-Initiator feature• Non-disruptive maintenance and microcode

upgrades

These basic Symmetrix features provide protection against loss of system and data availability due to a power loss or failed component. A redundant design allows Symmetrix to remain online and operational during component repair. For example, if a power supply fails, the remaining power supplies share the load until the failed component is replaced. The system battery backup prevents any loss of data due to a power failure.

The Dual-Initiator feature offers data availability protection against a Symmetrix disk management component failure. With dual-initiator, each member of a disk director pair shadows the functions of the other disk director. That is, each disk director can service any or all of the devices attached to the disk director with which it is paired. This feature does

118 MANAGING CRITICAL DATA

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not, however, provide data availability in the event of a disk device failure. Should Symmetrix detect a disk management hardware failure, Symmetrix automatically reads from or writes to the disk devices it was unable to communicate with via the other disk director in the pair.

Symmetrix Data Integrity Protection Features

The Symmetrix 3330/5330 is designed with these data integrity features:

• Error checking, correction, and data integrity protection

• Disk error correction and error verification

• Cache error correction and error verification

• Periodic system checks

Error verification prevents temporary errors from accumulating and resulting in permanent data loss. Symmetrix also looks at the error verification frequency as a signal of a potentially failing component.

The periodic system check tests all components as well as microcode integrity. Symmetrix reports errors and environmental conditions to the host system as well as the EMC Customer Support Center.

Data Protection Options

Although the Symmetrix 3330/5330 has standard features that provide a higher level of data availability than conventional DASD, the options listed below ensure an even greater level of data recoverability and availability. These data protection options are configurable at the physical volume level so that different levels of protection can be applied to different data sets within the same Symmetrix system.

Symmetrix Data Management Overview 119

You can choose from the following Symmetrix data protection options to match your critical data requirements:

• Mirroring• RAID-S• Symmetrix Remote Data Facility (SRDF)• Dynamic Sparing

Mirroring (RAID 1)Option (Mission

Critical/ BusinessCritical)

Mirroring (RAID 1) provides the highest performance, availability, and functionality for all mission critical and business critical applications. With the Mirroring option, Symmetrix maintains two identical copies of a logical volume on separate disk devices. Should Symmetrix be unable to read data from one of a mirrored pair, it immediately retrieves the data from the other logical volume.

SymmetrixRemote Data

Facility (SRDF)

The Symmetrix Remote Data Facility (SRDF) provides automatic, information protection and business continuance solutions for mainframe and open systems hosts. SRDF offers host-independent data storage that duplicates production (source) site data at a logical volume level to a recovery (target) site transparently to users, applications, databases and host processors.

When a source system is down, SRDF enables fast switchover to the target copy data so that critical information is again available in minutes. SRDF provides complete business continuance capability during the unlikely event of a data center disaster or during planned events such as daily backups, scheduled maintenance, and data center migrations or consolidations. With SRDF, source and target site Symmetrix systems can be as near as adjacent to one another or thousands of miles apart. In either case, the same information protection capabilities are offered. After an event, SRDF can resynchronize data to the source or to the target system at the users’


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discretion, thereby ensuring information and database consistency.

For more information about SRDF refer to the Symmetrix Remote Data Facility Product Guide.

RAID-S Option(Business Online)

The Symmetrix RAID-S option RAID-S provides high availability data with good performance and higher usable storage capacity.

The data protection feature is based on a 3+1 volume configuration (3 data volumes to 1 parity volume).

Dynamic Sparing Dynamic Sparing is another data protection option for use in conjunction with Mirroring, RAID-S, or SRDF. It limits the exposure after drive failure and before drive replacement. With Dynamic Sparing, Symmetrix maintains a small pool of spare volumes that go into use only when Symmetrix detects a potentially failing device. It performs a fast copy of the data and uses the spare until the original device can be replaced.

Symmetrix Data Management Overview 121

5.2 Reliability and Availability FeaturesSymmetrix has several features that allow it to maintain data integrity and maximize system availability. This section discusses several features in detail.

Reliable Components

The philosophy of EMC is to design in maximum reliability and then to implement the design with the most reliable components available. Symmetrix uses components that have a mean time between failure (MTBF) of several hundred thousand to millions of hours for a minimal component failure rate. A redundant design allows Symmetrix to remain online and operational during component repair.

A periodic system check tests all components as well as microcode integrity. Symmetrix reports errors and environmental conditions to the host system as well as the EMC Customer Support Center.

Redundant Power Subsystem

The Symmetrix 3330/5330 has a modular power subsystem featuring a redundant architecture that facilitates field replacement of any of its components without any interruption in processing.

The Symmetrix 3330/5330 power subsystem connects to two dedicated or isolated AC power lines. If AC power fails on one AC line, the power subsystem automatically switches to the other AC line.

The two power supplies operate in a redundant parallel configuration. If a power supply module fails, the remaining power supply continues to share the load. Symmetrix senses the fault and reports it as an environmental error (error code 0472).


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System Battery Backup

The entire Symmetrix system is made nonvolatile via an onboard battery backup system. The battery backup system provides the means for destaging any fast write data that might be in cache if AC power is lost on both AC power lines to the unit. In addition to providing nonvolatility to the Symmetrix system, the batteries are fully capable of powering not only all electronic components, but also all HDAs during this time. This eliminates emergency power off situations, meaning that the disks are always powered down in an orderly manner, which extends their useful life considerably.

The backup battery subsystem allows Symmetrix to remain online to the host system for three minutes in the event of an AC power loss. This three minute window allows Symmetrix to support frequent power outages because the battery is able to fully recharge during Initial Microcode Load (IML) time. Symmetrix continually recharges the battery subsystem whenever it is under AC power.

The battery backup also prevents disk device failures due to the sharp power drops that occur during unexpected power interrupts. If power is restored before the battery timer expires, Symmetrix becomes available again without IML.

Symmetrix PowerFailure on

MainframeChannels

When a power failure occurs, all directors send a Unit Check status with the environmental-data present bit set to all channels (error code 047A). Power switches immediately to the backup battery and Symmetrix continues to operate normally. When the battery timer window elapses, Symmetrix presents SCU busy to prevent the host system from writing or reading any data at the unit. Symmetrix destages any Fast Write data still in cache to disk, spins down the disk devices and retracts the heads, and powers down, turning off the battery at that time. Symmetrix will respond “not operational” to the host after it powers down.

Reliability and Availability Features 123

Symmetrix PowerFailure on Open

Systems Channels

When a power failure occurs, power switches immediately to the backup battery and Symmetrix continues to operate normally. When the battery timer window elapses, Symmetrix presents a busy status to prevent the host system from writing or reading any data at the unit. Symmetrix destages any Fast Write data still in cache to disk, spins down the disk devices and retracts the heads, and powers down, turning off the battery at that time. Symmetrix will not respond to SCSI selections after it powers down.

Dual-Initiator Feature

Symmetrix has a dual-initiator feature that ensures continuous availability of data in the unlikely event of a Symmetrix disk management hardware failure. It does not provide data availability in the event of a disk device failure. This feature works by having two disk directors “shadow” the function of the other. That is, this feature gives each disk director the capability of servicing any or all of the devices of the disk director with which it is paired should one of the disk directors be unable to partially or fully service its own devices.

With dual-initiator, the disk directors work in pairs. (Figure 30.) Under normal conditions, each disk director services its disk devices. If the sophisticated fencing mechanisms of Symmetrix detect a disk management hardware failure, Symmetrix notifies the EMC Customer Support Center of the failure, and reads from or writes to the disk devices that its disk director pair was unable to communicate with without interruption. When the source of the failure is corrected, Symmetrix returns the I/O servicing of the two disk directors to their normal state.


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Figure 30. Symmetrix 3330/5330 Dual-Initiator Example



This sophisticated fencing mechanism determines a disk management hardware failure at two levels:

• Level 1: A director discovers through use of its online self-testing that one of its SCSI paths is failing. The director signals Symmetrix of this condition and the director it is paired with automatically takes control of the failing path.

• Level 2: Symmetrix determines a director has failed and fences it out. The director’s associated pair automatically takes control of all its devices.

In the following examples disk director 1 and disk director 2 are paired. Each Symmetrix 3330/5330 disk director services 16 disk devices.

Example 1: Disk director 1 fails. Disk director 2 automatically performs any I/O operations with all of the devices normally serviced by disk director 1 as well as all of its own disk devices with no interruption in processing.

Example 2: On disk director 1, processor a, primary SCSI bus C fails. On disk director 2, processor b, primary SCSI bus D fails. The devices of these failing buses are serviced as follows:

• The devices of failing bus C, are serviced by disk director 2, processor a, secondary SCSI bus C.

• The devices of failing bus D are serviced by disk director 1, processor b, secondary SCSI bus D.

The functioning primary buses on each of the disk directors continue to service their respective devices.

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Example 3: On disk director 2, processor A, primary SCSI buses C and D fail. The devices of these failing buses are serviced as follows:

• The devices of failing bus C are serviced by disk director 1, processor A, secondary SCSI bus C.

• The devices of failing bus D are serviced by disk director 1, processor A, secondary SCSI bus D.

The functioning primary buses of disk director 2 continue to service their respective devices.


In summary, dual-initiator provides the following advantages:

• Ensures continuous data availability if a Symmetrix disk management component fails

• Provides continuous operation by switching data pathing to the alternate disk director without interruption when a communications failure occurs with one or more disk devices

• Re-establishes normal data pathing after repair of the defective component

Dual-initiator also provides an additional level of data availability in mirrored configurations. If Symmetrix is unable to read from or write to one of the devices in a mirrored pair, Symmetrix automatically uses the other disk device in the pair without interruption. If Symmetrix fails to communicate with that device also, Symmetrix then attempts to access the volume through the alternate path provided by the dual-initiator function.

Non-disruptive Component Replacement

Symmetrix, with its redundant architecture, supports non-disruptive replacement of many of its components. This includes online replacement of the directors (channel directors and disk directors), memory cards, disk devices, power supplies, communications cards, and cooling fans.

This non-disruptive replacement capability allows the EMC Customer Engineer to install a new component, initialize it if necessary, and bring it online without:

• Disrupting access to unaffected volumes• Powering down the Symmetrix unit• Stopping the operating system• Taking unaffected channel paths offline• Taking devices offline (other than the affected

device)


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Symmetrix remains fully operational while being serviced. For a demonstration of non-disruptive component replacement, contact your EMC Customer Service representative.

When replacing a Fast-Wide SCSI Director, all activity on the director must be stopped before attempting this operation.

Microcode Upgrades and Loads

Microcode upgrade and interim updates, performed remotely by the Product Support Engineers (PSE) at the EMC Customer Support Center, provide enhancements to performance algorithms, error recovery and reporting techniques, diagnostics, and microcode fixes.

Non-disruptiveMicrocode

Upgrades andLoads

Non-disruptive microcode upgrades from one version to the next and interim updates are available for Symmetrix systems. Symmetrix takes advantage of its multiprocessing and redundant architecture to allow for hot loadability of similar microcode platforms. Release levels can be non-disruptively loaded without interruption to user access.

During a non-disruptive microcode upgrade, the Product Support Engineer downloads the new microcode to the service processor. The new microcode loads into the EEPROM areas within the channel and disk directors and remains idle until requested for hot load in control storage. The Symmetrix system does not require manual intervention on the customer’s part to perform this function. All channel and disk directors remain in an online state to the host processor, thus maintaining application access. Symmetrix will load executable code at selected “windows of opportunity” within each director hardware resource until all directors have been loaded.


Once the executable code is loaded, internal processing is synchronized and the new code becomes operational. This capability can be utilized to upgrade or to back down from a release level or interim update.

During a non-disruptive microcode load within a code family, the full microcode is loaded, which consists of the same base code plus additional patches that reside in the patch area.

DynamicReconfiguration

Symmetrix supports dynamic reconfiguration activity without disruption to online applications, such as:

• Establish/de-establish mirrored pairs• Add/reallocate hyper-volumes• Modify channel assignments or change

emulation modes

OnlineSCSI-to-Fibre

Channel Migration

Beginning with microcode revision 5265, Symmetrix systems with SCSI channel directors can be upgraded to Fibre Channel directors without taking non-SCSI channels offline and without requiring a backup and restore of data. This capability allows customers with SCSI channels to take advantage of the connectivity and distance features offered with Fibre Channel directors. EMC Customer Engineers use a new utility to perform the migration.

For more information on Fibre Channel migration, consult your EMC sales representative.


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5.3 Data Integrity ProtectionSymmetrix preserves data integrity by performing extensive error checking and correction on all data and addresses it passes internally.

Error Checking, Correction, and Data Integrity Protection

In conventional DASD, the subsystem adds error checking and correction bytes to each data record field, as shown in Figure 31. It uses these error checking and correction bytes to check the data and correct it if possible. If it detects an uncorrectable error, the DASD subsystem informs the host that it has encountered bad data to avoid affecting data integrity.

Figure 31. Data Record Format for Conventional DASD

Symmetrix, like conventional DASD, performs this level of error checking and correction when it passes data and addresses. Symmetrix, however, goes further to ensure that the information passed belongs to the record specified. It does this by including additional bytes with the data field of each record. These bytes contain the record ID and a double LRC (Longitude Redundancy Code) check byte as shown in Figure 32. Symmetrix uses these bytes to check that the data is from the specified record and alarms the host if it is not. This second level of protection further ensures data integrity by preventing incorrect data from being transferred.

Data Integrity Protection 131

Figure 32. Symmetrix Data Record Format

Symmetrix has three levels of error detection. Should an error be undetected at one level, it will be detected at one of the other levels.

Symmetrix uses the following error correction and detection methods:

• Parity• Error Checking and Correction (ECC)• Longitude Redundancy Code (LRC)

Parity All data and control paths have parity generating and checking circuitry that verify hardware integrity at the byte level.

ECC The directors detect and correct single-bit and double-bit errors and report uncorrectable 3-bit or more errors in cache.

LRC The LRC calculation further assures data integrity. The check bytes are the XOR (exclusive OR) of the accumulated bytes. Each record in memory also includes its LRC byte, its physical memory address, and block number.

Disk Error Correction and Error Verification

The disk directors use idle time to read data and check the polynomial correction bits for validity. If a disk read error occurs, the disk director reads all data on that track to Symmetrix cache memory. The disk director writes several worst case patterns to that track searching for media errors. When the test completes, the disk director rewrites the data from cache to the disk device, verifying the write


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operation. The disk microprocessor maps around any bad block (or blocks) detected during the worst case write operation, thus skipping defects in the media. If necessary, the disk microprocessor can reallocate up to 32 blocks of data on that track. To further safeguard the data, each disk device has several spare cylinders available. If the number of bad blocks per track exceeds 32 blocks, the disk director rewrites the data to an available spare cylinder. This entire process is called “error verification.”

The disk director increments a soft error counter with each bad block detected. When the internal soft error threshold is reached, the Symmetrix service processor automatically dials the EMC Customer Support Center and notifies the host system of errors via sense data. It also invokes dynamic sparing (if the Dynamic Sparing option is enabled). This feature maximizes data availability by diagnosing marginal media errors before data becomes unreadable.

Cache Error Correction and Error Verification

The disk directors use idle time to periodically read cache, correct single-bit errors (one hard and one soft), and write the corrected data back to cache. This process is called “error verification.” When the directors detect an uncorrectable error in cache, Symmetrix reads the data from disk and takes the defective cache memory block offline until an EMC Customer Engineer can repair it. Error verification maximizes data availability by significantly reducing the probability of encountering an uncorrectable error by preventing bit errors from accumulating in cache.

In the mainframe host environment, Symmetrix reports uncorrectable bit errors as Equipment Checks to the CPU. These errors appear in the IBM EREP file.

Data Integrity Protection 133

5.4 Data Protection GuidelinesThe Symmetrix data protection options ensure a higher level of data protection, recoverability, and availability than the standard Symmetrix availability and reliability features. The following options listed in Table 18 can be purchased separately and implemented into the Symmetrix operation.

▼ CAUTION: To ensure continuous data availability, EMC strongly recommends that you use one or more of the data protection schemes for your Symmetrix volumes as described in Table 18.

Table 18. Data Protection Options

Data Protection Option Description

Mirroring (RAID-1) Provides the highest level of performance and availability for all mission critical and business critical applications by maintaining a duplicate copy of a volume on two disk devices.

For more information, refer to Mirroring on page 135.

RAID-S Provides higher performance and availability than RAID level 5 offerings for business online applications. A RAID-S group consists of three data volumes to one parity volume.

For more information refer to Symmetrix RAID-S on page 138.

Symmetrix Remote Data Facility (SRDF)

Provides an information protection/ business continuance solution by maintaining a mirror image of data in two Symmetrix systems which can be in physically separate locations.

For more information, refer to Symmetrix Remote Data Facility on page 154.

Dynamic Sparing Increases data availability by copying the data on a failing volume to a spare volume until the original device is replaced. Dynamic sparing is used as additional protection for mirrored, RAID-S, and SRDF volumes. For more information, refer to Dynamic Sparing on page 155 and Dynamic Sparing as Additional Protection on page 158.


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Mirroring 135

5.5 Mirroring Mirroring provides the highest level of performance and availability for all mission critical and business critical applications. Mirroring maintains a duplicate copy of a logical volume on two physical disk devices. Symmetrix maintains these copies internally by writing all modified data to both devices. The mirroring operation is transparent to the host.

The mirroring feature designates two logical volumes residing on different physical devices as a mirrored pair, one volume being mirror-1 and the other volume being mirror-2. The host views the mirror-1 and mirror-2 volumes as the same logical volume because each has the same unit address.

Write Operations with Mirroring

Symmetrix handles a write operation to a mirrored logical volume as a normal write operation. The channel director presents channel end and device end (or a good ending status) to the channel after data is written to and verified in cache. The disk directors then destage the data to each drive of the mirrored pair of drives asynchronously. As such, Mirroring on Symmetrix exploits the 100 percent fast write capability, and the application does not see additional time associated with having to physically perform two disk write I/Os (one to each drive of the mirrored pair) as is normally associated with RAID 1.

Read Operations with Mirroring

During read operations, if the data is not available in cache, Symmetrix reads the data from the disk pointed to by its performance algorithm for best system performance. The performance algorithms track path busy information as well as actuator location and what sector is currently under the disk head in each device. If a data check occurs on the device being read, Symmetrix automatically reads the data from the other device.

The Symmetrix performance algorithms for read operations offer three service polices to best balance the use of the Symmetrix architecture:

• Interleave Service Policy shares the read operations of the mirrored pair by reading tracks from both disk devices in an alternating method, a number of tracks from M1, and a number of tracks from M2. Interleave is designed to achieve maximum throughput.

• Split Service Policy differs from Interleave because read operations are assigned to either the M1 or the M2, but not to both. In the case of multiple hyper-volumes in the mirrored pair, certain logical volumes are read exclusively from M1 and certain logical volumes are read exclusively from M2. Split is designed to minimize head movement.

• Dynamic Mirror Service Policy (DMSP) utilizes both Interleave and Split for maximum throughput and minimal head movement. DMSP adjusts each logical volume dynamically based on access patterns detected.

Error Recovery with Mirroring

In the unlikely event that one volume in the mirrored pair fails, Symmetrix automatically uses the other volume without interruption of data availability. The Symmetrix system notifies the host operating system of the error via the message to operator protocol


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(mainframe systems only) and to the EMC Customer Support Center via an Auto-Call action. The EMC Customer Support Center Product Support Engineer (PSE) then begins the diagnostic process and, if necessary, dispatches a Customer Engineer (CE) to the customer site.

Once the defective disk device is nondisruptively replaced, the Symmetrix system re-establishes the mirrored pair and automatically resynchronizes the data with the new disk. During the data resynchronization process, the Symmetrix system gives priority to host I/O requests over the copy I/O to minimize the impact on performance. All new writes take place to both devices. The time it takes to resynchronize the mirrored pair depends on the I/O activity to the volume, the disk device, and the disk capacity.

Mirroring Advantages

In summary, mirroring offers the following advantages:

• Improved performance over traditional RAID 1 by supporting 100 percent fast write, and two simultaneous internal data transfer paths

• Protection of mission-critical data from any single point of failure

• Continuous business operation by switching to the alternate disk device of a mirrored pair without interruption to data availability should loss of access occur to one of the disk devices in a mirrored pair

• Assurance that the second copy of data is identical to the first copy

• Automatic resynchronization of the mirrored pair after repair of the defective volume

Mirroring 137

5.6 Symmetrix RAID-SRAID-S (Redundant Array of Independent Disks-Symmetrix) is a combination of hardware and software functionality that improves data availability in Symmetrix 3330 and 5330 ICDA systems by using a portion of the array to store redundancy information. This redundancy information, called parity, can be used to regenerate data if the data on a disk drive become unavailable.

The following sections describe how RAID-S functions in Symmetrix systems and how it differs from conventional RAID.

• RAID-S Technology• Data Protection Flexibility• RAID-S Components• RAID-S Modes of Operation• Writing Data in a RAID-S Group• Reading Data in a RAID-S Group• Data Recovery with RAID-S• RAID-S Advantages

RAID-S Technology

RAID-S employs the same technique for generating parity information as many other commercially available RAID solutions, that is, the Boolean operation EXCLUSIVE OR (XOR). However, EMC’s RAID-S reduces the overhead associated with parity computation by moving the operation from controller microcode to the hardware on the XOR-capable disk drives. Additional XOR hardware assist built into the Symmetrix cache memory boards further distributes the XOR function throughout the system to improve performance in the regeneration mode of operation.

The RAID-S data protection feature for all Symme-trix systems achieved the RAID Advisory Board's


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(RAB) second highest data availability and protec-tion classification -- Failure Tolerant Disk System Plus (FTDS+). All Symmetrix systems with SRDF and RAID-S achieved the RAID Advisory Board’s high-est availability and protection classification -- Disas-ter Tolerant Disk Systems Plus (DTDS+).

Data Protection Flexibility

Compared to a mirrored Symmetrix, RAID-S offers more usable capacity than a mirrored system containing the same number of disk drives. Like the mirroring or dynamic sparing options, RAID-S parity protection can be dynamically added or removed. For example, for higher performance requirements and high availability, parity protection on a RAID-S group can be turned off and the volumes in the RAID-S group mirrored. Within the same Symmetrix system, data can be protected via RAID-S, mirroring, and/or SRDF. Dynamic sparing can be added to any of these data protection options.

RAID-S Components

A RAID-S group consists of the physical disk devices within the Symmetrix unit that are related to one another for common parity protection. The RAID-S group is defined by the EMC Customer Engineer at the time Symmetrix is installed, and includes disk volumes that are designated as either data volumes or parity volumes.

The following sections describe these RAID-S components:

• RAID-S Groups• Logical Volumes• Rank• Data Volume• Parity Volume• Hyper-Volume Extension with RAID-S

Symmetrix RAID-S 139

RAID-S Groups A RAID-S group is the set of four physical disks within a Symmetrix system that are related to each other for parity protection. RAID-S has a 3+1 configuration, which results in 4 volumes per RAID-S group (3 data volumes to 1 parity volume). With this approach, effectively 75% of the total storage capacity of each RAID-S group of volumes is available for storing data.

Symmetrix systems employ dual-processor disk directors. These disk director boards are divided into an ‘a’ side and a ‘b’ side with each side supporting 2 SCSI paths (labeled ‘C’ and ‘D’). For optimum availability and redundancy, members of a RAID-S group should be configured to span across multiple disk directors. The overriding configuration requirement is that each member of a RAID-S group must be on a different SCSI path on the back end of the system. Examples of valid RAID-S group definitions are depicted in Figure 33.

Figure 33. RAID-S Group Definitions

Logical Volumes A logical volume is a unit of storage implemented on a single Symmetrix disk drive. When Hyper-Volume Extension (HVE) is not used, the size of a logical volume is usually the same as a physical volume. With HVE, up to 32 logical volumes can exist on a physical volume.

Disk Director

a b

DC DC

Disk Director

a b

DC DC

Disk Director

a b

DC DC

Disk Director

a b

DC DC

RAID Group 1 RAID Group 2 RAID Group 3


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Rank A rank is the set of logical volumes related to each other for parity protection. Each RAID-S group supports a minimum of one rank, and with Hyper-Volume Extension (HVE) enabled, a maximum of 32 ranks. Figure 34 shows a RAID-S group consisting of four 9 GB drives with one rank defined across the group. A rank is the “horizontal layer” of logical volumes that utilize different SCSI paths on different disk directors.

Figure 34. RAID-S Group Without Hyper-Volumes

Data Volume A data volume is similar to a traditional logical volume. It is the “virtual volume” image presented to the host operating system and defined as a separate unit address to the host. All data volumes within a rank must be the same size. There can be a maximum of 1,024 data volumes in Symmetrix 3330 and 5330 systems.

It is important to note that RAID-S does not “stripe” data across members of a rank as is done in many other RAID implementations. Each data volume emulates either a complete 3380 or 3390 device or a complete FBA logical volume mapped to an open systems host. This is a key differentiator because it allows the group to sustain the loss of more than one member and still service requests from all the surviv-ing members. In conventional parity-based RAID implementations that stripe data, the loss of more than one member would result in data loss for the

Device 03Device 03Device 02Device 01Device 00

RANKParity ABCVolume CVolume BVolume A

Data Volume Parity VolumeData VolumeData Volume


entire group. This “direct” mapping of disk images to disk drives also allows standard performance and tuning techniques to be used to manage the volumes in the rank.

Parity Volume A parity volume is a logical volume that holds the parity information for the rank. It must be the same size as the data volumes it supports. Parity volumes do not have unit addresses and are transparent to the host software. As is true with the “M2” volumes in a mirrored Symmetrix, parity volumes are not included in the 1,024 device limit within a single Symmetrix system.

Hyper-VolumeExtension with

RAID-S

Symmetrix Hyper-Volume Extension (HVE)1 is supported with RAID-S. When using HVE, parity and data volumes are distributed amongst the members of a RAID-S group, as shown in.

For more information on the Symmetrix Hyper-Volume Extension feature, refer to the Hyper-Volume sections in Chapter 4.

Figure 35. RAID-S Group With Hyper-Volumes

1. Symmetrix 3330 3.5-inch 9 GB disks attached to AS/400 hosts support RAID-S configurations. However, configurations of RAID-S with Hyper-Volume Extension are currently not supported.

Volume L60 cyl.

Volume I3390-3

Volume F3390-3

Parity ABC3390-3

Device 03

Volume L60 cyl.

Volume I3390-3

Volume F3390-3

Parity ABC3390-3

Device 03

Volume K60 cyl.

Volume H3390-3

Parity DEF3390-3

Volume C3390-3

Device 02

Volume J60 cyl.

Parity GHI3390-3

Volume E3390-3

Volume B3390-3

Device 01

Parity JKL60 cyl.

Volume G3390-3

Volume D3390-3

Volume A3390-3

Device 00

RANK

DataVolume

ParityVolume


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HVE not only allows multiple logical volumes to be allocated to one physical volume, but those logical volumes that are members of a RAID-S group can be distributed across the multiple physical drives in horizontal ranks. The parity volume for each rank can reside on any physical volume within the RAID-S group, as long as it is a different physical volume than those that comprise the data volumes of that rank. This distributed parity provides for improved performance over a single physical volume which could become a performance bottleneck in a heavy write workload. It also provides the performance advantages normally associated with RAID-5 striping, without the disadvantages of data volume striping.

When using HVE and RAID-S, all volumes that comprise the RAID-S ranks of a physical RAID-S group must be identical in format (all 3390-1, all 3390-3, 3390-9, FBA, etc.) Separate RAID-S physical groups on the same Symmetrix system can support different hyper-volume configurations. For example, the configuration shown in Figure 35 could co-exist on the same Symmetrix with a different RAID-S group that comprised eight 3390-1 hyper volumes.

RAID-S Modes of Operation

This section describes the following RAID-S modes of operation:

• Normal Mode/Parity Generation• Reduced Mode/Regeneration• Non-RAID Mode• Parity Rebuild

NormalMode/ParityGeneration

When a RAID-S rank is operating with all data and parity volumes functioning, it is said to be operating in normal mode. In normal mode, Symmetrix accom-plishes data redundancy by using the standard par-ity RAID Exclusive OR (XOR) logic to generate and store XOR parity data that can then be used to recon-struct the data of a failed drive. In parity generation,


a parity volume is initially formed by performing an XOR calculation on the contents of all member data volumes and writing the resulting parity to the par-ity volume. This bit-by bit parity generation is illus-trated in the first example of Figure 36.

Figure 36. Parity Protection Logic

ReducedMode/Regenera-

tion

When a RAID-S rank is operating with one failed data volume it is said to be running in reduced mode. Referring to Figure 34 on page 141, the failure of device 00 would force the rank to operate in reduced mode. In Figure 35 on page 142, the failure of device 00 would cause the first three ranks to operate

⊕ ⊕

⊕ ⊕

⊕ ⊕


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in reduced mode. In reduced mode, parity protection is suspended for the rank. The data on the failed vol-ume is reconstructed by XORing the parity volume with the remaining data volumes in the same rank. This process is called regeneration. Regeneration is shown in the bottom two examples of Figure 36.

Non-RAID Mode When a RAID-S rank is operating with one failed parity volume it is said to be running in non-RAID mode. As in reduced mode, parity protection is suspended for the rank. The failure of device 00 would cause the fourth rank to operate in non-RAID mode (see Figure 35 on page 142).

Parity Rebuild When a parity volume fails, RAID-S protection is suspended for the rank. When the failed device is replaced as part of a service action, the parity volume is reconstructed. This process is called parity rebuild.

Writing Data in a RAID-S Group

As with all Symmetrix operating modes, 100 percent of writes are fast writes and are satisfied in cache. In a destaging write operation, the channel director presents a channel end/device end (or a good ending status) message to the host after data is written and verified in cache.

In the RAID-S write process, performing the read old data and XOR functions at the disk device level reduces the disk director’s operations to a single read (difference data) and two writes (new data to the data volume and difference data to the parity volume).

Figure 37 on page 146 illustrates how data is destaged to disk through the following sequence of SCSI commands Symmetrix uses in the RAID-S write process:

• XD-Write-Read• XP-Write


Figure 37. RAID-S Write Operations

ComparingRAID-S with

Conventional RAID

The RAID-S write process is significantly different from other parity-based RAID implementations. The typical RAID implementation requires four discrete, sequential I/O operations be executed by the controller:

• Read old data.• Read old parity.• Write new data.• Write new parity.

In addition, two processing steps must be executed by the controller microcode:


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• XOR old data with new data (creating difference data).

• XOR difference data with old parity (creating new parity).

In contrast, RAID-S requires only two discrete sequential I/O operations be executed by the controller.

• Write new data.• Write difference data.

The design of RAID-S distributes the work of computing parity between the disk director and the disk drives, using the XOR chip located on the disk drive and the disk level buffer. The disk containing the data volume performs the read of the old data, XORs it with the new data to compute difference data, and sends the difference data to the disk director, which then places the data in cache. The disk containing the parity volume reads the old parity, XORs it with the difference data received from the cache and writes the new parity to the disk.

The parallelism introduced into the parity computation process through the use of XOR drives allows the “controller” (disk director) to do only half the number of back end I/Os as competitive RAID solutions. This reduces the impact of the write penalty significantly and improves the overall performance of RAID-S compared to competitive implementations.

Reading Data in a RAID-S Group

Read hit operations in a RAID -S group are processed via cache as in normal Symmetrix processing. Read misses are directed to the disk drive and processed as normal Symmetrix read misses. There is no XORing of the data, and only one disk drive is involved in servicing the request. This can offer an advantage over other implementations that “stripe” data across multiple disk drives. In these implementations more


than one disk drive may be required to service the request, resulting in possible contention when multi-ple I/Os are serviced simultaneously.

Data Recovery with RAID-S

RAID-S provides continuous availability for all data in a RAID-S group should any single physical device fail or become unavailable within that RAID-S group. In the event of a media error, the affected tracks will be regenerated. When a volume within the RAID-S group fails or becomes unavailable the RAID-S group is put in reduced mode (Figures 38 and 39) and parity protection for the data volumes in the RAID-S group is immediately turned off. These volumes will now serve all their I/O requests as standard data volumes. All data is still available to the host, but is unprotected against additional failures unless protected by dynamic sparing.

Should a data volume report too many errors, or fail outright, that volume will be taken off-line by the Symmetrix subsystem. This condition causes the Symmetrix to place a remote service call to the Customer Support center. The Product Support Engineer at the support center will determine if a disk drive has been identified for replacement and dispatch a customer engineer (CE). Once on site, the CE will start the Symmetrix interactive drive replacement process. The logical volumes on the disk being replaced will be placed in a not ready state and the associated ranks will begin either reduced mode or non-RAID mode of operation (depending on whether or not the logical volume that was made not ready contained data or parity information). Once the new drive is in place, the rebuild process begins.

If Symmetrix is configured with dynamic sparing, Symmetrix copies the data from the failing volume to the spare, reconstructing the data if necessary from parity. Symmetrix also invokes available spares for the remaining volumes in the RAID-S group, if they are available. For more information on dynamic


5

sparing used with RAID-S, refer to Dynamic Sparing with RAID-S Volumes on page 161.

Write Requests ona Failing Volume

As write requests are made to the failing data volume, the new data is XORed with the old data and the new parity is written to the parity drive. Symmetrix follows the process shown in Figure 38.

Figure 38. Writing to a RAID-S Group in Reduced Mode

Read Requests ona Failing Volume

Read requests for data in cache (read hit) are serviced immediately from cache. As a read request to access data from the failing volume is received, the data is automatically calculated in cache from the XOR of the parity volume and the remaining active data vol-umes (Figure 39 on page 150). Then, from cache, the

DISK DIRECTORS

BUS

2.

CACHE

3.Write P' (new parity)to parity drive.

SCSI SCSI SCSISCSI

2. Read A and B data to cachefrom surviving rank members.C' B = P' (new parity).⊕ ⊕A

4. Subsequent write requests to C result in regenerating datafrom the A, B, and ABC Parity disks.Writes to A or B are normalRAID-S writes.

B C ABC PARITYA

2. 3.

1.Write new C data (C')to cache.

1.

C' A B⊕ ⊕


regenerated data is delivered to applications that request it.

If frequent read requests are made of the regenerated data it will remain in cache according to the Most Recently Used (MRU) cache tables. (For more information on MRU refer to Symmetrix Cache Management on page 75). If the data is not in cache, it is again recalculated from the remaining active drives and delivered to the applications that request it.

Figure 39. Reading from a RAID-S Group in Reduced Mode

DISK DIRECTORS

BUS

2.

CACHE

SCSI SCSI SCSISCSI

4. Subsequent read requests to C result in regenerating datafrom the A,B, and ABC Parity disks.

3. Return regeneratedC data to host.

1. Read old paritydata to cache.

2. Read data to cache fromsurviving rank members.Parity A B =regenerated C data.

⊕ ⊕ REGENERATEDC DATA

B C ABC PARITYA

PARITY A B⊕ ⊕

2. 1.

2.

3.


5

Data VolumeFunction when a

Parity Volume Fails

Should the parity volume fail, the active data volumes within the RAID-S group stop creating parity, and function as normal standard data volumes in non-RAID mode. Since data associated with individual logical volumes is not striped across multiple volumes, no single drive is dependent upon the availability of any other drive in the RAID-S group to provide access to its own data. All volumes on the remaining drives are available.

Data Recoverywith RAID-S and

HVE

Data recovery in RAID-S when using HVE is logically identical to RAID-S recovery without HVE. As an example, in Figure 35 on page 142, assume that Volume B starts exceeding error thresholds and is about to fail. The Symmetrix data protection mechanisms then decide to remove Volume B. Parity is immediately stopped within the entire RAID-S group, and all subsequent requests to read or write to Volume B will be served by the Parity ABC volume, as described in Symmetrix Remote Data Facility on page 154. As read or write requests are made to Volumes E and J, data will be regenerated from the data and parity volumes in their respective ranks. Nothing needs to be done with Parity GHI, since it is now ignored. After the physical drive upon which Volumes B, E, and J resided is replaced, the data in these volumes will be regenerated, and then the parity volumes rebuilt. Parity protection is now available.

RegeneratingData or Rebuilding

Parity After DiskReplacement

After the failed disk device has been replaced, data is regenerated for the data volumes or parity is rebuilt for the parity volume. For the data volume(s) on the replaced disk device, data is regenerated from the parity volume and the remaining data volumes in the RAID-S group. For the parity volume on the replaced disk device, parity is rebuilt from the RAID-S group’s data volumes (Figure 40). Once this process completes, Symmetrix re-establishes parity protection for all volumes of the RAID-S group, and resumes normal mode operation.


Figure 40. Regenerating Data or Parity After Disk Replacement

RAID-S Advantages

In summary, RAID-S offers the following advantages:

• High performance, even in the event of a disk failure within a RAID-S group. When a disk failure occurs, all logical volumes that were not physically stored on the failed disk device will perform at the level typical of standard Symmetrix devices.

A

DISK DIRECTORS

BUS

CACHE

Replace failed drive. For a replaced parity drive, rebuild parity fromthe data volumes. For a replaced data drive, regenerate data fromthe surviving data drives and the parity drive.

1. Data from rank members and/orparity (depending on the replaced disk)is read to cache.

SCSI SCSI SCSISCSI

2.A B C=regenerated dataor parity

⊕ ⊕ 3. Standard Write.A B C data toreplaced disk.

⊕ ⊕

A B C⊕ ⊕

BA CRegenerated

Data orParity

1. 1. 1. 3.

2.


5

• Regardless of a disk failure within a RAID-S group, including multiple disk failures, as long as the physical disk device is operational, some of the data remains accessible.

• Protects a volume requiring high availability from being a single point of failure.

• Reduced front-end I/O operations for write operations improves system performance.

• Automatically restores parity protection on the cache-level to the RAID-S group after repair of a defective device.


5.7 Symmetrix Remote Data Facility The Symmetrix Remote Data Facility (SRDF) option is an information protection/ business continuance solution that maintains a mirror image of data at a logical volume level in two to five Symmetrix systems located in physically separate sites.

SRDF offers two disaster recovery solutions:

• Campus Solution• Extended Distance Solution

The SRDF Campus Solution allows Symmetrix units to be located up to 60 km (37.5 miles) apart using fiber-optic links. Synchronous, semi-synchronous, or Adaptive Copy data copying operational modes are available for this solution. This implementation supports both uni-directional and bi-directional SRDF configurations.

The SRDF Extended Distance Solution allows the Symmetrix units to be located over 60 km apart using a T3 or E3 link. Synchronous, semi-synchronous, or Adaptive Copy data copying modes of operation are available for this solution. To minimize the degrada-tion of performance due to distance and telecommu-nications delays EMC recommends using the semi-synchronous mode. This implementation mode supports only uni-directional SRDF configurations.

SRDF is transparent to the host operating system and host applications. It does not require additional host software for duplicating data on the Symmetrix units at the geographically separate sites. The participating Symmetrix units manage all SRDF functions.

SRDF protection is also available for locally mirrored volumes. For more information about SRDF, refer to the Symmetrix Remote Data Facility Product Guide.


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5.8 Dynamic Sparing Symmetrix has a dynamic sparing option that reserves volumes as standby spares. These volumes are not user-addressable. The dynamic sparing function determines when a logical volume is about to fail and copies the contents of the disk device on which that volume resides to an available spare without any interruption in processing (Figure 41). Symmetrix notifies the EMC Customer Support Center of this event with an Environmental-Data Present error and then uses the spare until the device on which the original logical volume resides can be replaced.

This option increases data availability without impacting performance. It is used in combination with Mirroring, RAID-S, or SRDF.

Figure 41. Dynamic Sparing Process

Dynamic Sparing 155

When dynamic sparing is enabled, Symmetrix makes its copying decision based on error statistics maintained by its directors, the intelligent disk microprocessor self-testing information, and its active error checking system. If the Symmetrix dynamic sparing algorithms determine that the number of errors occurring on a volume is excessive and that a hard failure is probable, it looks for an available spare in its small pool of spares. It dynamically copies all data from the device containing the failing volume to the available spare. Symmetrix continues to process host I/O requests at the highest priority while this copy operation takes place to minimize the effect on performance. When the copy operation completes, Symmetrix notifies the EMC Customer Support Center of the event. The spare and the original device work as a mirrored pair until the defective unit is replaced.

The EMC Customer Engineer (CE) replaces the disk experiencing the failure while the failing disk is online. After the disk is replaced, the CE then issues commands for Symmetrix to dynamically copy the contents of the spare to the new device. The spare remains in use until the copy completes. When the copy has completed, the CE issues commands for Symmetrix to return the spare to its pool, making it available should another volume fail in the future.

Dynamic sparing has the added benefit of allowing an EMC Customer Engineer operating onsite or from the EMC Customer Support Center to force Symmetrix to copy the contents of a device to an available spare. This forced copy allows the EMC Customer Engineer to test or service a disk device non-disruptively while access to data continues.


5

In summary, dynamic sparing offers the following advantages:

• Increases protection of all volumes from loss of data

• Automatically activates the spare volume without interruption prior to loss of access of a potentially failing volume

• Ensures that the spare copy is identical to the original copy

• Resynchronizes a new disk device with the dynamic spare after repair of the defective device is complete

• Increases data availability of all volumes in use without loss of any data capacity

• Dynamic sparing is transparent to the host and requires no user intervention.

Dynamic Sparing 157

5.9 Dynamic Sparing as Additional Protection

Dynamic sparing is used as additional protection for volumes already protected by the Symmetrix mirroring, RAID-S, or SRDF options.1 Dynamic sparing provides incremental protection against failure of a second disk during the time between when a disk is taken offline and when it is ultimately replaced and resynchronized. Your EMC Customer Engineer implements dynamic sparing by reconfiguring Symmetrix using the AutoInstall option.

Dynamic Sparing with Locally Mirrored Pairs

When a dynamic spare is invoked for a locally mirrored pair, Symmetrix automatically augments the original mirrored pair with a dynamic spare volume that joins the mirror pair as an additional or (third) mirror (Figure 42). Data is copied to the dynamic spare volume from the failing volume. If any data cannot be copied from the failing volume it is copied from the other mirror. Symmetrix continues processing I/Os with the spare functioning as a mirror with no interruption in operation.

The failing disk can then be replaced and resynchronized with the mirror group. Then the dynamic spare can be returned to the spare pool.

1. Symmetrix 3330 3.5-inch 9 GB disks attached to AS/400 hosts support dynamic sparing for RAID-S volumes. However, dynamic sparing for RAID-S volumes with Hyper-Volume Extension is currently not supported.


5

Figure 42. Dynamic Sparing with Locally Mirrored Pairs Dynamic Sparing with RAID-S Volumes

Dynamic Sparing with RAID-S Volumes

In a Symmetrix RAID-S system, all data volumes of the RAID-S group will be spared if there are enough dynamic spares available for all the data volumes. When a device is failing in a RAID-S group, Symmetrix will first try to copy data from the failing device to the first spare (Figure 43). If Symmetrix cannot copy from the failing device to the spare, it then uses the parity algorithms to reconstruct the data for the failing device and then copies the data to the spare. As read or write requests are made of the failing volume, the data is regenerated. Regenerated read data is sent to the requesting application. Write data is regenerated as described in Table 38 on page 149. Symmetrix also invokes available spares for the remaining data devices in the RAID-S group, with these data device spares functioning as

Dynamic Sparing as Additional Protection 159

mirrored pairs. (Symmetrix now treats the invoked spare device as a mirror to the RAID-S data volumes.)


5

Figure 43. Dynamic Sparing with RAID-S Volumes

Dynamic Sparing as Additional Protection 161

Data DeviceFailure

If the failing data volume becomes not ready before it can be replaced, Symmetrix turns off parity protec-tion, recalculates the data for the failed device from the remaining data devices and parity volume and places the regenerated parity data on the parity device for the RAID-S group. The dynamic spare–parity drive functions as a mirrored pair for that data volume. RAID-S protection is not available until the failing device is replaced. All volumes of the RAID-S group will be spared if there are three dynamic spares available. If there are not enough spares for the remaining data volumes in the group, Symmetrix will invoke as many dynamic spares as are available for the RAID-S group.

Parity DeviceFailure

When Symmetrix detects that a parity volume is failing, Symmetrix turns off parity protection, and mirrors all data volumes to available spares. RAID-S protection is not available until the failing device is replaced. If there are not enough spares for the data volumes in the group, Symmetrix will invoke as many dynamic spares as are available for the RAID-S group.

Dynamic Sparing with Remotely Mirrored Pairs (SRDF)

When the dynamic sparing option is invoked for a remotely mirrored SRDF pair, Symmetrix automati-cally activates an available spare in the Symmetrix unit containing the failing device and copies data from the failing device to the spare. Symmetrix con-tinues processing I/Os with the spare functioning as one of a mirrored pair with the failing device and its remote mirror with no interruption in operation. If Symmetrix cannot copy all data from the failing device to the spare, it will retrieve the unavailable data from the “good” member of the remote pair.

For a description of SRDF, refer to Symmetrix Remote Data Facility on page 154. For examples of dynamic sparing in SRDF configurations, refer to the Symmetrix Remote Data Facility Product Guide.


6

Chapter 6 ERROR REPORTING AND RECOVERY

The information presented in this chapter is only applicable to Symmetrix units connected to mainframe hosts.

This chapter discusses the types of errors possible when Symmetrix is connected to a mainframe host. It also discusses error handling techniques, and an error recovery summary.

• Types of Errors .................................................... 164• Error Reporting ................................................... 168• EREP Reports....................................................... 173• Error Handling .................................................... 175

163

6.1 Types of ErrorsThere are several types of errors associated with data storage. The error type is indicated in the sense information, and in error messages and reports. You should be aware, however, that the error type doesn’t necessarily identify the source or the cause of the problem.

The error types detected by Symmetrix include:

• Data Check - Symmetrix has detected an error in the bit pattern read from the disk. Data checks are due to hardware problems when writing or reading data, media defects, or random events.

• System or Program Check - The Symmetrix microcode has rejected the command. This condition is attributable to the construction of the channel program. This type of error is indicated to the processor and is always returned to the requesting program.

• Overrun - Symmetrix cannot receive data at the rate it is transmitted from the host system. This error indicates a timing problem. Resubmitting the I/O operation again normally corrects this error.

• Equipment Check - Symmetrix has detected an error in the operation of its hardware.

Temporary and Permanent Errors

Whenever Symmetrix detects a data or equipment error, either Symmetrix or the operating system will attempt to recover from the error, depending on the situation and the type of hardware involved. Error recovery can be temporary or permanent.

164 ERROR REPORTING AND RECOVERY

6

An error is temporary if Symmetrix or the operating system can recover from the error successfully. The application is not notified of a temporary error. Temporary errors recovered within Symmetrix are not reported in the error report unless its internal soft error threshold has been exceeded. Temporary errors recovered by the operating system are logged by the host error recovery procedures (ERP). When requested, Symmetrix generates sense bytes and sends them to the operating system. These sense bytes define the error.

An error is permanent from a system view if neither the operating system nor Symmetrix can recover from the error condition. For example, a channel director may cause a data check error. That data check is permanent to the system, and is recorded in the error recording data set (ERDS) as a permanent path error. However, if the host system retries the read from an alternate path, and the data is read successfully from Symmetrix, the system does not notify the application of the error, so the error is not permanent to the application. If the read on the alternate path was not successful, the data check is permanent from both the system and application points of view.

Recoverability by Error Type

An error is recoverable if the application does not see it as a permanent error.

Data Check When data is written, Symmetrix records check bytes with the data to enable data check detection. These are the error checking and correction (ECC) bytes. These bytes often provide sufficient information for Symmetrix to reconstruct the data should an error occur. When Symmetrix reconstructs the data using the ECC bytes, the data check is ECC-correctable.

Types of Errors 165

ECC-correctable data checks are always recoverable. Symmetrix relocates the block as necessary.

When Symmetrix cannot reconstruct the data using the ECC bytes, the data check is ECC-uncorrectable. Here, Symmetrix retries the I/O operation. If the retry is unsuccessful, the data check is uncorrectable. This is a permanent error to the Symmetrix.

For Symmetrix systems protected by mirroring, the data check is not reported to the application. The data is provided to the host via the protection mechanism (mirroring) and Symmetrix places a remote service call.

ICKDSF ControlStatement

For an uncorrectable data check on an unprotected Symmetrix, use the following ICKDSF control statement to reformat the home address and record zero of the track.

Do NOT use ICKDSF to assign alternate tracks in the classic IBM manner since no alternate will be assigned.

This control statement may require an operator response to permit purging of datasets on the volume. Refer to the ICKDSF User’s Guide and Reference for more information.

▼ *** WARNING *** All data remaining on the track(s) operated on by this control statement will be DESTROYED. Restore the data from your most recent backup. Use of any means other than that shown below to reallocate data will affect data integrity.


6

Enter the following DSF control statement to reassign the defective track(s):

INSPECT UNIT(ccuu)|SYSNAME(sysxxx)|DDNAME (ddname)

DEVTYPE(3380|3390) VERIFY (serial) NOPRESERVE NOASSIGN NOMAP -

TRACKS((cyl,head),...)

Specify the desired (cyl,head) in decimal notation, or as (X’cyl’,X’head’) if hex notation is desired.

Overrun Errors andEquipment

Checks

When an overrun or equipment check is detected, the host system retries the operation. If the operation is successful on the retry, the error is recorded as recoverable. If the retry is unsuccessful, the error is recorded as unrecoverable.

Types of Errors 167

6.2 Error Reporting

For error reporting specific to the Symmetrix Remote Data Facility (SRDF) environment, refer to the Symmetrix Remote Data Facility Product Guide.

Symmetrix reports error conditions to the host and to the EMC Customer Support Center via its Autocall feature. Symmetrix presents a unit check status in the status byte to the channel whenever it detects an error condition such as a data check, command reject, overrun, or equipment check.

Symmetrix also presents a unit check status (environmental-data present) whenever it detects an environmental violation. Symmetrix runs a series of internal tests on its components at least once every 24 hours and monitors critical components continuously. It also runs these tests when initially powered up or when a software reset has occurred. These tests check for a low battery charge or AC power failure, or redundant component failure such as the failure of one device in a mirrored pair or the activation of dynamic sparing.

If, while running its environmental tests, Symmetrix detects an error condition, it sets a flag to indicate a pending error and presents a unit check status to the host on the next SIO. Symmetrix then schedules the test that detected the error condition to be rerun in more frequently. (Each test has specific deltas to regulate its execution). If a device level problem is detected and reported, subsequent failures of that device are not reported until the failure is fixed. If a second type of failure is detected for a device while there is a pending error reporting condition in effect, Symmetrix reports the pending error on the next SIO and then the second error.


6

When Symmetrix presents a unit check status, the host retrieves the sense data from Symmetrix and, if logging action has been requested, places it in the Error Recording Data Set (ERDS). The EREP (Environment Recording, Editing, and Printing) program prints the error information. The sense data identifies the condition that caused the interruption and indicates the type of error and its origin. The format of the sense data can be found in the appropriate IBM reference manuals. For interpretation of the EREP reports, the appropriate IBM manual should be consulted.

Symmetrix reports the exception conditions listed in Table 19 to the host as Service Alerts. In 3990 controller emulation, the returned sense data is in SIM format. In 3880 emulation, environmental data is returned. In both cases the code listed will be contained in sense bytes 22-23. These messages are reported across all logical paths to the device experiencing the error.

Table 19. Environmental Alert Messages

Sense Bytes 22-23 Meaning

E460 Dynamic sparing was invoked by a disk director

1463 A disk director dual initiator failed to IMPL monitor (’DD’)

E466 Hot sparing was automatically invoked by a disk director for an RDF device in the other system

E467 RDF initiated SIM message

E46D All RDF links are not operational

E46E All RDF links are operational now

1470 Over temperature condition

1471 Low battery/high charge state

1472 Symmetrix power subsystem alarm

E473 Locally mirrored drive (source volume) is in a “not ready” state

E474 Locally mirrored drive (source volume) is write disabled

Error Reporting 169

Event Messages Table 20 describes the events that appear at the host console. These events are reported at the time they occur and also appear at the Symmetrix service processor. They are not reported to the EMC Customer Support Center. The next section shows the format of these messages.

E475 Remotely mirrored drive is in a "not ready" state

1476 Service processor not responding

1477 AutoCall failed to complete to EMC Customer Support Center

1478 12V On

1479 Environment cable missing

147A AC line failure or interruption

147B High charge state not detected within 2 minutes of power up; or, Clock inconsistency found between Symmetrix and service processor; or,Director inserted without system reset

147C Latched alarms

147D SRDF adapter link problem

147E An RDF link is operational now

147F Service processor called home to report an error condition (customer option)

Table 19. Environmental Alert Messages


Table 20. Event Messages


0464 Migration has completed for all migration devices

E451 Event trace trigger. PC should call home.


6

Operator Messages

On MVS, SIM messages will be displayed as IEA480E Service Alert Error messages. They have the format shown in Figure 44 and Figure 45.

Figure 44. MVS IEA480E Service Alert Error Message Format (AC power failure)

Figure 45. MVS IEA480E Service Alert Error Message Format (mirror-1 volume in “not ready” state)1

E461 M2 is resynchronized with the M1 device after M2 is brought back to ready

E462 M1 is resynchronized with the M2 device after M1 is brought back to ready

E465 Device resynchronization process has begun

Table 20. Event Messages (Continued)


Error Reporting 171

Symmetrix also reports events to the host and to the service processor. These events are:

• The mirror-2 volume has synchronized with the source volume.

• The mirror-1 volume has synchronized with the target volume.

• Device resynchronization process has begun.

On MVS, these events are displayed as IEA480E Service Alert Error messages. They have the format shown in Figure 46 and Figure 47.

Figure 46. MVS IEA480E Service Alert Error Message Format (mirror-2 resynchronization)

Figure 47. MVS IEA480E Service Alert Error Message Format (mirror-1 resynchronization)

1. All host channel paths to that device (target volume) will report this error message. Therefore, this same message may appear several times.


6

6.3 EREP ReportsThe Environmental Record Editing and Printing (EREP) program is an applications program that runs under the MVS, VM, and VSE operating systems. EREP helps you monitor the functioning of various units in your system such as the processor, I/O devices, controller, and channels by supplying information on errors that have occurred in these components.

When an error occurs, the operating system creates a record from the data captured by the hardware or software and writes it in the Error Reporting Data Set (ERDS). EREP reads records directly from the ERDS and processes them to produce the report or reports you request.

EREP Error Records

Refer to the EREP User’s Guide and Reference for the formats of these records.

EREP uses the information in these records to produce many types of reports. There are three System Exception Reports applicable to disk media errors with Symmetrix. These reports are listed below in the order you use them to identify and handle a media error situation.

EREP Reports 173

• System Error Summary (Part 2) - This report lists permanent I/O errors (data or equipment checks) and identifies each error by job name and time.

• Subsystem Exception DASD - This report lists accumulated permanent and temporary I/O errors.

• DASD Data Transfer Summary - This report presents details on data checks.

See the EREP User’s Guide and Reference for information on how to define report requests to meet your needs.


6

6.4 Error HandlingAs part of your routine maintenance procedure, you should generate System Exception Reports daily. From these reports, you can determine whether errors are permanent or temporary, the number of errors that have occurred, and their frequency.

If your system reports permanent errors occurring on Symmetrix, save the Subsystem Exception DASD report output and contact your EMC Customer Engineer.

If your system reports that temporary data check errors are occurring on Symmetrix, and you consider the number of temporary errors for a volume to be excessive, notify your EMC Customer Engineer.

Table 21 below describes the error handling process you should follow for Symmetrix.

Detecting the Error

Review the System Error Summary (Part 2) to determine if permanent errors are occurring on Symmetrix. This report lists permanent I/O errors in sequence according to the time they occurred. Also review the Subsystem Exception DASD report. This report highlights problems related to data storage that may need further investigation. It gives the

Table 21. Error Handling Steps

Step Task Tool(s) Actions

1 Detect error occurrence

System Error Summary (Part 2) report (permanent errors)Subsystem Exception DASD report (temporary errors)

If permanent error, or if temporary error requires investigation, perform Step 2.

2 Determine source of errors using EREP

Subsystem Exception DASD report

If the source is hardware, call EMC Customer Engineer.

Error Handling 175

number and frequency of both permanent and temporary errors.

You can use this information to defer further handling of a particular error based on its recoverability status, location, and frequency, or take immediate action to correct the error source.

▼ CAUTION: Permanent data errors with a probable failing unit of VOLUME require your IMMEDIATE attention!

Determining Error Source

If the System Error Summary (Part 2) and Subsystem Exception DASD reports indicate problems with a Symmetrix device, review the Subsystem Exception DASD report to determine the failing component. This report lists error information by volume. It identifies the failing volume, the track location of the failure, the sense information received from Symmetrix at the time of the last failure, and the permanent and temporary error counts on that device.


A

Appendixes

This section includes the following appendixes:

A Sense Byte Information ...................................... 179B Symmetrix 3330/5330 Specifications ............... 185C Power Sequences ................................................ 201D Planning and Installation .................................. 209

177

178 APPENDIXES

A

Appendix A SENSE BYTE INFORMATION

The information presented in this appendix is only applicable to Symmetrix disk devices connected to mainframe hosts.

This appendix describes the sense byte data Symmetrix presents to the mainframe host when it detects an error condition.

• Overview.............................................................. 180• Console Error Message ...................................... 181• Host Sense Byte Data Formats.......................... 184

179

A.1 OverviewSymmetrix presents a unit check status in the status byte to the channel whenever it detects an error condition. The error condition can be one of the error types associated with data such as a data check, command reject, overrun, or equipment check.

The channel issues a sense command to retrieve the sense data from Symmetrix. The host places the sense data in the Error Recording Data Set (ERDS) where the EREP subsequently uses it for its reports.

Sense byte error data may also appear on the system operating console. The format of the error data reported to the operator console depends on your operating system. Sense byte data at the host is presented in 24-byte mode for 3880 controller emulation and 24-byte compatibility mode or 32-byte mode for 3990 emulation.

180 SENSE BYTE INFORMATION

A

A.2 Console Error MessageFigure 48 is an example of a typical MVS console error message for 24-byte sense data.

Figure 48. Typical Console Error Message

The unit status and channel status (CSW characters) indicate why the operation terminated. The unit status is bits 32-39 in the CSW (370 mode) and bits 0-7 of Word 2 of the SCSW (XA and ESA mode). The channel status is bits 40-47 in the CSW (370 mode) and bits 8-15 of Word 2 of the SCSW (XA and ESA mode).

I0S000I xxx, xx, xxx-xxx, xx, xxxx, xxx-xxx, xxx-xxx, xxxxxx, xxxxxxxx

DEVICE NUMBER

COMMAND CODE (2 CHARACTERS)

SENSE DATA (4 TO 48 CHARACTERS)

VOL ID (6 CHARACTERS)

ERROR DESCRIPTION (12 CHARACTERS)

CSW STATUS (4 CHARACTERS:0-1 = UNIT STATUS, 2-3 = CHANNEL STATUS)

SEEK ADDRESS (12 CHARACTERS)

JOB ID (8 CHARACTERS)

CHANNEL PATH ID

Console Error Message 181

Unit Status Bits Table 22 lists and describes the unit status bits.

Table 22. Unit Status Bits

370 XA, ESA Meaning

Bit 32 Bit 0 Attention - READY status when set in conjunction with Device End and Unit Exception

Bit 33 Bit 1 Status modifier - when set with Unit Check, indicates an usual condition - command retry; when set with Busy, indicates Symmetrix busy; when set with Device End, next CCW has been skipped

Bit 34 Bit 2 Control-unit end - Symmetrix no longer busy

Bit 35 Bit 3 Busy - if Status Modifier clear, the drive is busy; if Status Modifier set, the channel director is busy

Bit 36 Bit 4 Channel end - data or command transfer to/from channel is complete

Bit 37 Bit 5 Device end - device operation complete

Bit 38 Bit 6 Unit check - Symmetrix detected an error condition

Bit 39 Bit 7 Unit exception - EOF on addressed track during a Read R0, Read IPL, or Read CKD, or Write Key Data or Write Data operation. If Attention and Device End set, indicates a READY status


A

Channel Status Bits

Table 23 lists and describes the channel status bits.

You can find a detailed description of these status bits in the appropriate IBM Principles of Operation.

Table 23. Channel Status Bits

370 XA, ESA Meaning

Bit 40 Bit 8 Program-controlled interruption (PCI) - CCW specified interrupt occurred

Bit 41 Bit 9 Incorrect length - number of bytes transferred were not equal to number of bytes specified by CCW

Bit 42 Bit 10 Program check - CCW programming error

Bit 43 Bit 11 Protection check - Channel attempted to address a storage area prohibited by a protection key

Bit 44 Bit 12 Channel-data check - incorrect parity

Bit 45 Bit 13 Channel-control check - channel hardware error

Bit 46 Bit 14 Interface-control check - invalid signal from Symmetrix (invalid signal sequence, overly slow response, or parity error on Bus In)

Bit 47 Bit 15 Chaining check - channel overrun during input operation

Console Error Message 183

A.3 Host Sense Byte Data Formats

Sense byte formats are found in the IBM reference manual appropriate for the specific Symmetrix emulation.


B

Appendix B SYMMETRIX 3330/5330 SPECIFICATIONS

This appendix contains the specifications of the Symmetrix Model 3330/5330 Integrated Cached Disk Array.

• Storage Control ................................................... 186• Physical Data ....................................................... 194• Environmental Data ........................................... 196• Power and Cooling Data ................................... 197• Power Requirements .......................................... 199

185

B.1 Storage Control

Emulation 3990-3, 3990-2, or 3990-6

Channel Speeds 1.0 to 1.5 (interlock)

3.0 or 4.5 MB/second (data streaming)

Up to 17 MB/sec (serial channel)

Up to 20 MB/sec (FWD SCSI channel)

Up to 40 MB/sec (Ultra SCSI channel)

Up to 100 MB/sec (Fibre channel)

StorageCapacities

Tables 24 through 26 outline the Symmetrix models 3330-xx/5330-xx capacities when Symmetrix is attached to mainframe and open systems hosts1. The capacities are presented based on the method of data protection:

• SRDF (Symmetrix Remote Data Facility)• Mirroring (RAID-1)• RAID-S

1. For Symmetrix 3330/5530 3.5-inch 9 GB disk drive capacities when attached to AS/400 hosts, contact your EMC sales representative. Currently, the Symmetrix 3330/5330 3.5-inch 18 GB disk drives do not support split 9 GB volume configurations to AS/400 hosts.

186 SYMMETRIX 3330/5330 SPECIFICATIONS

B

Table 24. Symmetrix 3330-18/5330-18 SRDF Capacities

Number of Physical Devices

Mainframe Systems Capacity (GB)

Open Systems Capacity (GB) a Min/Max Cache (MB)

4 71 672 (7210) 512/8,192

8 143 1342 (14410) 1,024/8,192

12 214 2022 (21710) 1,280/8,192

16 286 2692 (28910) 1,280/8,192

24 429 4042 (43410) 2,048/8,192

32 572 5392 (57910) 2,048/8,192

a. The GB2 value is based on the convention: 1 GB = 1024x1024x1024.

The GB10 value is based on the convention: 1 GB = 1000x1000x1000.


Table 25. Symmetrix 3330-18/5330 18 Mirrored (RAID-1) Capacities



Open Systems Capacity (GB) a Min/Max Cache (MB)

4 35 332 (3610) 512/8,192

8 71 672 (7210) 512/8,192

12 107 1012 (10810) 768/8,192

16 143 1342 (14410) 1,024/8,192

24 214 2022 (21710) 1,280/8,192

32 286 2692 (28910) 1,536/8,192

a. The GB2 value is based on the convention: 1 GB = 1024x1024x1024 bytes. The GB10 value is based on the convention: 1 GB = 1000x1000x1000 bytes. Although these values are expressed differently, their values are equivalent.

Storage Control 187


Table 26. Symmetrix 3330-18/5330-18 RAID-S Capacities


Mainframe Systems Capacity (GB)a

Open Systems Capacity (GB) b Min/Max Cache (MB)

4 53 502 (5410) 512/8,192

8 107 1012 (10810 1,024/8,192

12 161 1512 (16210) 1,024/8,192

16 214 2022 (21710) 1,536/8,192

24 322 3032 (32510) 2,048/8,192

32 429 4042 (43410) 3,072/8,192

a. RAID-S disk device capacities are based on the ratio of 3 data devices to 1 parity device.

b. The GB2 value is based on the convention: 1 GB = 1024x1024x1024 bytes. The GB10 value is based on the convention: 1 GB = 1000x1000x1000 bytes. Although these values are expressed differently, their values are equivalent.

Table 27. Symmetrix 3330-9/5330-9 SRDF Capacities



Open Systems Capacity (GB) a

Min/Max Cache (MB)

4 3510 332 (3610) 512/4,096

8 7110 672 (7210) 512/4,096

12 10710 1012 (10810) 768/4,096

16 14310 1342 (14410) 1,024/4,096

24 21410 2022 (21710) 1,280/4,096

32 28610 2692 (28910) 1,280/4,096

a. The GB2 value is based on the convention: 1 GB = 1024x1024x1024 bytes.



B

Table 28. Symmetrix 3330-9/5330-9 Mirrored (RAID-1) Capacities



Open Systems Capacity (GB) a

Min./Max.Cache (MB)

4 1710 162 (1810) 512/4,096

8 3510 332 (3610) 512/4,096

12 5310 502 (5410) 512/4,096

16 7110 672 (7210) 512/4,096

24 10710 1012 (10810) 768/4,096

32 14310 1342 (14410) 1,024/4,096

a. The GB2 value is based on the convention: 1 GB = 1024x1024x1024 bytes.



Table 29. Symmetrix 3330-9/5330-9 RAID-S Capacities


Mainframe Systems Capacity (GB) a

Open Systems Capacity (GB) a b

Min./Max.Cache (MB)

4 2610 252 (2710) 512/4,096

8 5310 502 (5410) 512/4,096

12 8010 752 (8110) 768/4,096

16 10710 1012 (10810) 1,024/4,096

20 13410 1262 (13510) 1,024/4,096

32 21410 2022 (21710) 1,280/4,096

a. RAID-S disk device capacities are based on the ratio of 3 data devices to 1 parity device.

b. The GB2 value is based on the convention: 1 GB = 1024x1024x1024 bytes.



Storage Control 189

MB/Volume1

by Emulation Type

Bytes/Track

Bytes/Cylinder

Cylinders/Volume

1. Fixed Block Architecture (FBA) capacities are based on 512 bytes per block, 64 blocks per track, and 15 tracks per cylinder.

3380D emulation 6303380E emulation 1,2603380K emulation 1,8903380K(+) emulation 2,3783380K(++) emulation 2,8433390-1 emulation 9463390-2 emulation 1,8923390-3 emulation 2,8383390-9 emulation 8,514

3380 emulations 47,4763390 emulations 56,664FBA 32,768

3380 emulations 712,1403390 emulations 849,960FBA 491,520

3380D emulation 8853380E emulation 1,7703380K emulation 2,6553380K(+) emulation 3,3393380K(++) emulation 3,9933390-1 emulation 1,1133390-2 emulation 2,2263390-3 emulation 3,3393390-9 emulation 10,017


B

Cylinders/LogicalVolume,

18 GB Drives(Open Systems)

Cylinders/LogicalVolume,

9 GB Drives (OpenSystems)

Ratio of Physical to Logical Volumes

Cylinders per Logical Volumea

a. Cylinder counts are based on 512 byte blocks.

1:1 b

b. To utilize full disk capacity, the 18 GB disk devices should be configured with at least 2 logical volumes in the sizes shown in the table above. However, if the maximum logical device size is required, split the 18 GB devices into two logical volumes of the following cylinder sizes: 32,510/4,318.

1:2 18,414 1:3 12,2751:4 9,206 1:5 7,364 1:6 6,1361:7 5,259 1:8 4,602 1:9 4,090

1:10 3,681 1:11 3,3461:12 3,0671:13 2,831 1:14 2,628 1:15 2,453 1:16 2,300

Ratio of Physical to Logical Volumes

Cylinders per Logical Volume a

a. Cylinder counts are based on 512 byte blocks. For cylinder counts of Symmetrix 3330 9 GB drives attached to AS/400 hosts, consult your EMC sales representative.

1:1 18,4141:2 9,2061:3 6,1371:4 4,602

Storage Control 191

GB/ LogicalVolume,

18 GB Drives(Open Systems)

Ratio of Physical to Logical Volumes Capacity (GB)a

a. The GB2 value is based on the convention:

1 GB = 1024x1024x1024 bytes. The GB10 value is based on the convention:

1 GB = 1000x1000x1000 bytes. Although these values are expressed differently, their values are equivalent.

1:1 b

b. To utilize full disk capacity, the 18 GB disk devices should be configured with at least 2 logical volumes in the sizes shown in the table above. However, if the maximum logical device size is required, split the 18 GB devices into two logical volumes of the following cylinder sizes: 32,510/4,318.

1:2 8.42 GB2 (9.05 GB10)1:3 5.61 GB2 (6.03 GB10)1:4 4.21 GB2 (4.52 GB10)1:5 3.37 GB2 (3.62 GB10)1:6 2.80 GB2 (3.01 GB10)1:7 2.40 GB2 (2.58 GB10)1:8 2.10 GB2 (2.26 GB10)

1:9 1.87 GB2 (2.01 GB10)1:10 1.68 GB2 (1.80 GB10)1:11 1.53 GB2 (1.64 GB10)1:12 1.40 GB2 (1.50 GB10)1:13 1.29 GB2 (1.39 GB10)1:14 1.20 GB2 (1.29 GB10)1:15 1.12 GB2 (1.20 GB10)1:16 1.05 GB2 (1.13 GB10)


B

GB/ LogicalVolume,

9 GB Drives (OpenSystems)

Disk Device FormFactor

Symmetrix 18 GBor 9 GB disk devices 3.5 inches

Ratio of Physical to Logical Volumes Capacity (GB) a b

a. The GB2 value is based on the convention:1 GB = 1024x1024x1024 bytes. The GB10 value is based on the convention: 1 GB = 1000x1000x1000 bytes. Although these values are expressed differently, their values are equivalent.

b. For capacities of Symmetrix 3330 9 GB drives attached to AS/400 hosts, consult your EMC sales representative.

1:1 8.42 2 (9.0510)1:2 4.21 2 (4.5210)1:3 2.802 (3.0110)1:4 2.10 2 (2.2610)

Storage Control 193

B.2 Physical Data

Depth 36 inches (91.4 cm)

Width 22.5 inches (57.2 cm)

Height 46 inches (116.9 cm)

Weight(18 GB Devices)

Weight(9 GB Devices)

Access (Raised)Floor Tile

Requirements

EMC recommends 24-inch access (raised) floor tiles that will support the following minimum loads:

Number of Physical Devices Weight lbs Weight kg

4 571 2598 583 265

12 595 27016 607 27620 619 28124 631 28628 643 29232 655 297

Number of Physical Devices Weight lbs Weight kg

8 583 26512 595 27016 607 27624 631 28632 655 297

Minimum Load Requirements Load WeightStatic Concentrated Load 1000 lbs. (454 kg)Dynamic Rolling Load for

minimum of 10 passes1000 lbs. (454 kg)


B

Service Area1

Floor Space (withservice area)

1. An additional 1 foot (30.5 cm) of side clearance is recommended so that the Symmetrix 3330/5330 doors can be opened fully.

Front 36.0 inches (91.5 cm)Rear 36.0 inches (91.5 cm)

15.7 sq. ft. (1.4 sq. m)

Physical Data 195

B.3 Environmental Data

OperatingTemperature

59 - 90°F (10 - 38°C)

Operating AltitudeMaximum

8,000 ft. (2500 m)

OperatingHumidity

20 - 80% non-condensing


B

B.4 Power and Cooling Data

PowerConsumption/

Heat Dissipation(18 GB Disk

Devices)

Number of Devices

Power Consumption

(KVA)a

a. These values represent the maximum power consumption and heat dissipation under steady state operation for a configuration of 4 channel directors, 2 disk directors, and 8 GB of memory.

Heat Dissipation(BTU/Hour)a

4 .79 2,703

8 .90 3,064

12 1.00 3,424

16 1.11 3,784

24 1.32 4,505

32 1.53 5,226

Power and Cooling Data 197

PowerConsumption/

Heat Dissipation(9 GB Disk

Devices)

Air VolumeGenerated

Number of Devices

Power Consumption

(KVA)a,b

a. These values represent the maximum power consumption and heat dissipation (under steady state operation) that you can expect for your particular model. Your Symmetrix unit may perform better than those values shown here.

b. These values are calculated for a configuration of 4 channel directors, 2 disk directors, and 2 GB of memory under steady state operation.

Heat Dissipation(BTU/Hour)a, b

8 .682 2,327

12 .773 2,639

16 .864 2,951

20 .956 3,263

24 1.047 3,575

28 1,139 3,887

32 1.230 4,199

English Units Metric (SI) Units1,080 30.59


B

B.5 Power RequirementsThe dedicated or isolated AC power line(s) meeting the specifications below must be located within 12 feet of the Symmetrix 3330/5330 unit. The connector sockets should be located near the equipment and easily accessible.

Input Voltage

Range

Frequency

Line Cord

Circuit BreakerRequired

AC Connector(customer-supplied)

AC Plug(s)

North America International

208 VAC (208-240 VAC)

180-264 VAC (180-264 VAC)

60 Hz 50 Hz

single-phase single-phase

20A (20A)

Russellstoll 3913 (loose)AC connector-or-Russellstoll 3743 (fixed box)AC connector

Country specific, customer-supplied

Russellstoll 3720 Country specific, customer-supplied

Power Requirements 199

C

Appendix C POWER SEQUENCES

This appendix provides step-by-step instructions for powering the Symmetrix 3330/5330 on and off. The unit is powered on and off via the power switches on the rear door of the unit.

• Powering Up the Symmetrix 3330/5330 ......... 202• Routinely Powering Down Symmetrix ........... 204• Emergency Shutdown........................................ 205• Powering Up After an Emergency Shutdown 206

201

C.1 Powering Up the Symmetrix 3330/5330

▼ CAUTION: This unit contains no user-serviceable parts, so it should not be opened for any reason by untrained personnel. If the Symmetrix 3330/5330 is in need of repair, only qualified personnel familiar with safety procedures for electrical equipment and the Symmetrix 3330/5330 should access components inside the unit.

Perform these steps to power on the Symmetrix after it has been powered off by the AC power switch.

1. Make sure all operator panel switches (channel director and disk director) are in the disable position.

2. Lift the EPO switch on the rear door to the up (|) position.

3. Lift the AC power switch on the rear door to the up (|) position. Symmetrix begins its IML procedure. This procedure takes several minutes to perform.

The power controls are inoperative unless the Emergency Power Off (EPO) switch on the rear door is in its enabled (up, | position). The EPO switch when turned off (down, O position) disables all power to Symmetrix including the backup battery systems.

4. When the IML procedure completes (all directors show "0F" in their LED displays on their front panels), place the operator panel switches (channel director and disk director) in their enable position.

202 POWER SEQUENCES

C

When "0F" clears from all director LED displays, Symmetrix is then available to the host system(s).

Powering Up the Symmetrix 3330/5330 203

C.2 Routinely Powering Down SymmetrixPerform these steps to power off Symmetrix using the AC power switch.

1. Stop all processes to the Symmetrix 3330/5330.

2. Watch the operator panel and wait for all "Active" LEDs to stop flashing.

The displays stop flashing when the Symmetrix has written all cache data to disk.

3. Press the AC power switch on the rear door to the down (O) position.

The battery backup system automatically turns on when Symmetrix detects loss of AC power. The battery will keep Symmetrix powered for 3 minutes following which Symmetrix turns off.

204 POWER SEQUENCES

C

C.3 Emergency ShutdownIf it becomes necessary to power off Symmetrix immediately:

• Press the red EPO switch on the rear door to the down (O) position.

Symmetrix immediately switches to backup battery power and destages any pending writes in cache to disk. This destage operation takes approximately 20 seconds following which Symmetrix powers down.

Emergency Shutdown 205

C.4 Powering Up After an Emergency Shutdown

▼ CAUTION: This unit contains no user-serviceable parts, so it should not be opened for any reason by untrained personnel. If the Symmetrix 3330/5330 is in need of repair, only qualified personnel familiar with safety procedures for electrical equipment and the Symmetrix 3330/5330 should access components inside the unit.

When the Symmetrix 3330/5330 is powered down via the red EPO switch, a breaker switch on the power subsystem trips.

Perform these steps to power on the Symmetrix after it has been powered off by the red EPO switch.

▼ CAUTION: Always contact the EMC Customer Support Center prior to powering up Symmetrix after an emergency shutdown.

1. Make sure all operator panel switches (channel director and disk director) are in the disable position.

2. Lift the EPO switch on the rear door to the up (|) position.

3. Lift the AC power switch on the rear door to the up (|) position.

Symmetrix begins its IML procedure. This procedure takes several minutes to perform.

206 POWER SEQUENCES

C

4. When the IML procedure completes, all directors show "0F" in their LED displays.

▼ CAUTION: Before you enable channel and disk directors from the Symmetrix operator panel, contact an EMC Product Support Engineer (from the EMC Customer Support Center). Explain that an emergency shutdown was performed and that you need them to check the condition of the Symmetrix before you enable the channel and disk directors. When the Symmetrix checks out correctly, proceed to the next step.

5. Place the operator panel switches (channel director and disk director) in their enable position.

When "0F" clears from all director LED displays, Symmetrix is then available to the host system(s).

Powering Up After an Emergency Shutdown 207

208 POWER SEQUENCES

D

Appendix D PLANNING AND INSTALLATION

This appendix covers the tasks you need to perform when planning or verifying the physical configuration of Symmetrix in your system or creating I/O addressing schemes.

• Planning Overview............................................. 210• Director/Cache Card Layout ............................ 216• Mainframe Systems Installations ..................... 217• Open Systems Installation Checklists.............. 225

209

D.1 Planning OverviewThis section guides you through the physical details related to delivery and installation of the Symmetrix 3330/5330. It reviews all the necessary installation details performed by EMC personnel and outlines customer responsibilities.

Inform EMC of any labor union-based restrictions or security clearance requirements prior to delivery.

The Symmetrix 3330/5330 is designed for installation in a properly equipped computer room with raised floor, controlled temperature and humidity, proper air flow and ventilation, proper power and grounding, system cable routing facilities, fire equipment, etc. One or more planning sessions with your EMC Systems Engineer and Customer Engineer may be necessary to close on all the details related to installation. Table 30 below lists the responsibility summary at the first planning session.

Table 30. Pre-Installation Responsibility Summary

EMC Responsibility Customer Responsibility

Provide all details necessary for site planning and preparation.

Provide an environment which supports safe installation of the Symmetrix 3330/5330 and promotes its reliable long-term operation.

Complete and process the Installation Planning Task Sheet and Pre-Site Survey.

Provide appropriate power, cooling and ventilation, humidity control, floor load capability, and service clearances as required.

Arrange for shipment and delivery via appropriate method.

Participate in planning sessions as required to ensure a smooth and uncomplicated installation.

Install a properly working system as promised and on schedule.

210 PLANNING AND INSTALLATION

D

Physical Specifications

Physical Data on page 194, provides overall system dimensions and weights for the Symmetrix 3330/5330.

Transportation and Delivery Guidelines

Symmetrix 3330/5330 systems delivered within the United States or Canada travel by air-ride truck or van. The Symmetrix 3330/5330 is shrouded by custom-designed shipping material, crated and palleted. Integrated shock absorbing casters on which the Symmetrix 3330/5330 rests facilitates its movement during shipping and installation.

Symmetrix 3330/5330 systems delivered internationally normally require air freight and are therefore crated for shipment.

Unless otherwise instructed, the EMC Traffic Department arranges for delivery directly to the customer’s computer room. To ensure successful delivery of the Symmetrix 3330/5330, EMC has formed partnerships with specially selected moving companies. These companies have moving professionals trained in the proper handling of large and very sensitive systems. These companies provide the appropriate personnel, floor layments, and any ancillary moving equipment required to facilitate delivery.

Power Requirements

The Symmetrix 3330/5330 operates on 208 VAC single-phase input power at frequencies of 50 or 60 Hz. North American Symmetrix units are cable ready to plug directly into the customer’s prewired receptacles. International units arrive ready for hard-wiring at the customer’s facility.

Planning Overview 211

The customer is responsible for supplying and installing a dedicated AC power line and receptacle for the unit in advance of delivery. 1 EMC also recommends that these circuits reside on separate circuit panels. Refer to Power and Cooling Data on page 197 for specific information about the Symmetrix 3330/5330 power requirements.

External modems for North American Symmetrix units also require 110-VAC single-phase power. Voltage requirements for modems for International Symmetrix units are country specific.

Choosing a UPS Symmetrix is capable of supporting two consecutive three-minute power outages before its battery power supply is depleted. If you need to extend this time period, you will need to purchase a UPS from a qualified vendor.

When you are planning the UPS solution for the Symmetrix 3330/5330, and the host system is presently or is going to be protected with a UPS, the battery backup time you propose for the Symmetrix UPS solution should match that of the host system.

Environmental Specifications

The Symmetrix 3330/5330 requires the environmental specifications outlined in Appendix B, Symmetrix 3330/5330 Specifications. The customer must make sure the site meets or exceeds the specifications listed.

1. Symmetrix units with dual power cords require a dedicated AC power line and receptacle for each power cord.


D

System Cabling Requirements

The Pre-Site Survey completed with the EMC Systems Engineer reports the cable lengths (Bus & Tag, serial, or Fast-Wide or Ultra SCSI, or Fibre Channel) required for each host connection to Symmetrix. From a physical planning perspective, review the routing path(s) from the host(s) to the Symmetrix 3330/5330. Resolve any physical access issues before the installation date.

Layout and Space Requirements

Symmetrix requires the floor tile cutout illustrated in Figure 49 to accommodate the Bus and Tag, SCSI, serial channel, or Fibre Channel cables. Also refer to, For the service clearance requirements and access (raised) floor tile load requirements, refer to Physical Data on page 194.


Figure 49. Floor Tile Cutout

This floor tile cutout adequately accommodates the bus & tag cables for an all parallel channel configuration. Please note how closely the wheels are to the edge of the cutout. Make sure the rear wheels of the Symmetrix unit are locked when Symmetrix is rolled into position in the computer room. For access floor tile load requirements, Physical Data on page 194.


D

Remote Support Remote Support is an important and integral part of EMC’s Customer Service and Support strategy. Communication between the EMC Customer Support Center and the Symmetrix 3330/5330 occurs via the external modem connected to the Symmetrix 3330/5330 service processor.

This feature requires the customer to provide a dedicated telephone line (for the modem) and 110 VAC single-phase power for the external modem within 6 feet of the Symmetrix 3330/5330.


D.2 Director/Cache Card LayoutFigure 50 shows the channel director and cache memory layout om the Symmetrix 3330/5330 for a typical configuration.

The Symmetrix 3330, and Symmetrix 5330 with ESP, support open systems connectivity through Symmetrix Fast-Wide or Ultra SCSI channel configurations.

The Symmetrix 5330, and Symmetrix 3330 with ESP, support mainframe connectivity through serial channel directors for ESCON connections and parallel channel directors (Symmetrix 5330 systems only) for block multiplexer connections.

For SRDF Remote Link director configuration, refer to the Symmetrix SRDF Product Manual.

Figure 50. Symmetrix 3330/5330 Channel/Memory Configurations

CHANNEL/MEMORY CONFIGURATION

= DISK DIRECTOR

= CACHE MEMORY

= CHANNEL DIRECTOR

DD

CD

MEM

DD CD MEMDD CDMEM CD CD


D

D.3 Mainframe Systems Installations

For Fast-Wide SCSI installation requirements, refer to “Open Systems Installation Checklists” on page 225.

This section contains the following work sheets:

• Parallel Channel Path Assignments• Serial Channel Path Assignments, 2-port Serial

Channel Director, 4-port Serial Channel Director• Serial Channel Path Assignments, 2-port Serial

Channel Director• Volume Addresses and Cylinders• Volume Work Sheet

Table 31. Parallel Channel Path Assignments

Parallel Channel Director

CPU (Processor #)

CHPID or Channel #

Unit Address Range Channel Speed

15 Proc b, Port B

15 Proc b, Port A

15 Proc a, Port A

15 Proc a, Port B

16 Proc b, Port B

16 Proc b, Port A

16 Proc a, Port A

16 Proc a, Port B

Mainframe Systems Installations 217

Table 32. Serial Channel Path Assignments, 2-port Serial Channel Director

Serial Channel Director

CPU (Processor #)

CHIP or Channel #

ESCON Director #

Dir Port #a (host

channel)

Dir Port #a (Symmetrix connection)

3 Proc b, Port A

3 Proc a, Port A

14 Proc b, Port A

14 Proc a, Port A

15 Proc b, Port A

15 Proc a, Port A

16 Proc a, Port A

16 Proc b, Port A

a. IBM 9032/9033 or plug-compatible device


D

Table 33. Serial Channel Path Assignments, 4-port Serial Channel Director

Serial Channel Director

CPU (Processor #)

CHIP or Channel #

ESCON Director #

Dir Port #a (host

channel)

Dir Port #a (Symmetrix connection)

3 Proc b, Port A

3 Proc b, Port B

3 Proc a, Port B

3 Proc a, Port A

14 Proc b, Port A

14 Proc b, Port B

14 Proc a, Port B

14 Proc a, Port A

15 Proc b, Port A

15 Proc b, Port B

15 Proc a, Port B

15 Proc a, Port A

16 Proc b, Port A

16 Proc b, Port B

16 Proc a, Port B

16 Proc a, Port A

a. IBM 9032/9033 or plug-compatible device


Table 34. Volume Addresses and Cylinders

Device # Log Vol 1 Log Vol 2 Log Vol 3 Log Vol 4 Log Vol 5

1 Address

# Cylinders

2 Address

# Cylinders

3 Address

# Cylinders

4 Address

# Cylinders

5 Address

# Cylinders

6 Address

# Cylinders

7 Address

# Cylinders

8 Address

# Cylinders

9 Address

# Cylinders

10 Address

# Cylinders

11 Address

# Cylinders

12 Address

# Cylinders

13 Address

# Cylinders


D

14 Address

# Cylinders

15 Address

# Cylinders

16 Address

# Cylinders

17 Address

# Cylinders

18 Address

# Cylinders

19 Address

# Cylinders

20 Address

# Cylinders

21 Address

# Cylinders

22 Address

# Cylinders

23 Address

# Cylinders

24 Address

# Cylinders

25 Address

# Cylinders

26 Address

# Cylinders

27 Address

# Cylinders

Table 34. Volume Addresses and Cylinders (Continued)



28 Address

# Cylinders

29 Address

# Cylinders

30 Address

# Cylinders

31 Address

# Cylinders

32 Address

# Cylinders

Table 34. Volume Addresses and Cylinders (Continued)



D

Table 35. Volume Work Sheet

Device # EmulationMain Vol Address

Main Vol # of cyl

Ext Vol Address

Ext Vol # of cyl


Table 35. Volume Work Sheet (Continued)

Device # EmulationMain Vol Address

Main Vol # of cyl

Ext Vol Address

Ext Vol # of cyl


D

D.4 Open Systems Installation Checklists

This section contains hardware and host checklists to be used when connecting Symmetrix to open systems hosts. For additional information on open systems installations, refer to the Symmetrix Open Systems Environment Product Guide.

Symmetrix Hardware Checklists

Make sure you obtain from and discuss the following site profile information with the Customer Engineer and/or Systems Engineer. This information is necessary for each Symmetrix system you are installing.

If you are connecting Symmetrix 3.5-inch 9 GB drives to AS/400 and UNIX host(s), use the checklist in Table 36. If you are connecting Symmetrix 3.5-inch 9 GB drives exclusively to an AS/400 host(s), refer to Table 37.

Table 36. Symmetrix Checklist for UNIX or PC Server Hosts

Symmetrix Model

Total number of physical drives to be configured on the Symmetrix

Physical drive type (size)

Total amount of Symmetrix cache

Number of Fast-Wide SCSI channel directors a

Fast-Wide SCSI channel director model used

Number of Fast-Wide SCSI channels used per directors b

Remote link director (SRDF) type (RA-2, RA-4) and quantity

Will an AS/400 host be attached? c

a. If host mirroring is performed, configure an even number of Fast-Wide SCSI channel directors.

b. From a performance perspective, it is better to spread SCSI channels across as many Fast-Wide SCSI channel directors as possible.

c. If an AS/400 host is to be attached to a Symmetrix 3330/5330, the drives have to be formatted beforehand to a larger block size. This larger block size must be used for all drives accessed by the AS/400 as well as the open systems hosts.

Open Systems Installation Checklists 225

Host Checklists Make sure you discuss with and provide the following host information to the Customer Engineer and/or Systems Engineer. This information is necessary for each host you are attaching to Symmetrix. Make a copy of this form (Table 38) for each host you will attach to Symmetrix. When you finish you should have a checklist for each host. If you are connecting a Symmetrix 3330 3.5-inch 9 GB drives 1 to an AS/400 host, use the checklist in Table 39.

Table 37. Symmetrix 3330 Checklist for AS/400 Hosts

Symmetrix Model

Total number of physical drives to be configured

Physical drive type (size)

Total amount of Symmetrix cache

Number of Fast-Wide SCSI channel directorsa

Fast-Wide SCSI channel director part number used

Number of Fast-Wide SCSI channels used per directorsb

Number of dynamic spares

Will an open systems host also be attached? c

a. If host mirroring is performed, configure an even number of Fast-Wide SCSI channel directors.

b. From a performance perspective, it is better to spread SCSI channels across as many Fast-Wide SCSI channel directors as possible.

c. If an open system host is to be attached to Symmetrix 3330 3.5-inch 9 GB drives, the drives have to be formatted beforehand to a 520-byte block size. This 520-byte block size must be used for all drives accessed by open systems hosts.

1. Symmetrix 3330-18, 18 GB disk drives do not currently support connection to AS/400 hosts.


D

Table 38. UNIX or PC Server Host Checklist

Host Configuration Requirements Host 1 Host 2

Host (CPU) vendor and model number

Host controller type and model number

Memory capacity of host

O/S revision level of host

I/O rate per second expected per host

SCSI adapter used on host, type and model number

Is this a clustered environment? Which one?

Will devices be shared? Which ones?

Total number of SCSI channels per host, to which SA ports will they attach?

Specify if any narrow channels used

Number of logical devices needed per SCSI bus

Size of volumes required to be visible to hosta

Total customer usable data storage required

Will host-level mirroring be used, which volumes?

Will Symmetrix Dynamic Sparing be used?(specify number of spares) Which volumes?

Will Symmetrix RAID-1 be used? Which volumes?

Will Symmetrix RAID-S be used? Which volumes?

Will SRDF be used? Which volumes?

Data storage utilization per hostb

Average transfer size of data

Using raw devices or filesystems?

Size of filesystem

Will data striping be used?What type of data striping package?

Partitioning?

Partition sizes?


LVM usedc

What major applications are to be run?

Database used: Oracle®/Sysbase®/Informix®/other?

Size of database

Database release version

Supply typical high level database schema and queries

Any patches or modifications related to IO/SCSI?

Additional comments

a. This is the volume size needed for each volume visible on the SCSI bus

b. Percentage of available Symmetrix data capacity used by that host

c. Special attention is required when using a Logical Volume Manager (LVM) and/or data striping when using hyper-volumes. In general, EMC recommends using data striping on Symmetrix. Keep in mind that the larger the granularity of the striping, the less effective it becomes.

Table 38. UNIX or PC Server Host Checklist (Continued)

Host Configuration Requirements Host 1 Host 2


D

Table 39. AS/400 Host Checklist

Host 1 Host 2

Host (CPU) Model Number

Memory capacity of host

O/S revision level of host

Number of buses per hosta

Number of expansion racks per hosta

Number of IOP’s used and their bus/rack distribution a

Total number of SCSI channels per host

Number of devices per SCSI bus

Total customer usable data storage required

Host level mirroring/Symm RAID-1/Symm RAID-S b

When using Symmetrix RAID-S, do you want RAID-5 emulation to the host?

Data storage utilization per host c

Data storage added to System or user ASP?

Average transfer size of data

IO/sec currently performed per host (total)

What major applications are to be run?

What data storage unit is Symmetrix replacing?

Number of HDAs replaced vs. number of Symmetrix HDAsd

Old:New:

Old:New:

Data migration or reload?

Will performance or benchmarking be done? If so, describe tests, other vendors involved, etc.

Obtain AS/400 Performance Tool Data (if available)e


Additional comments

a. This information is critical for System Level Mirroring planning to ensure redundancy.

b. When host-level mirroring is required, Symmetrix devices are configured as non-mirrored with dynamic spare. Host-level mirroring is taxing on performance since all writes are performed twice and consume cache space until destaged to disk.

c. Percentage of available Symmetrix data capacity used by that host.

d. One of the factors strongly affecting performance is the number of HDAs involved in the configuration. If a large number of volumes is replaced by a small number of Symmetrix volumes, additional cache may be needed.

e. This will allow before/after DASD performance comparisons

Table 39. AS/400 Host Checklist (Continued)

Host 1 Host 2


D

SCSI Cable Work Sheet

The physical connection to a Fast-Wide or Ultra SCSI channel interface occurs at the connectors on the SCSI adapters located at the rear of the Symmetrix 3330/5330 unit. You can use Table 40 as a cable worksheet form.

When connecting to hosts with differential Fast-Wide or differential narrow SCSI interfaces, contact your EMC sales representative.

Table 40. SCSI Cable Worksheet

SCSI Director

SCSI Director

PortCable Length

RequiredCable Model Number

or Part NumberHost ID Model

Number

1a A

1a B

1b A

1b B

2a A

2a B

2b A

2b B

3a A

3a B

3b A

3b B

4a A

4a B

4b A

4b B


Fast-Wide or Ultra SCSI Channel Adapters

Several Fast-Wide SCSI adapters are available for Symmetrix, depending on the host channel connection requirements, such as terminated and non-terminated channels, and Y-cable cluster configurations. Refer to the Symmetrix Open Systems Environment Product Guide for information about choosing the Fast-Wide SCSI channel adapter that best suits your environment.

Contact your EMC sales representative to obtain SCSI adapter part numbers. For cluster configurations, refer to the Symmetrix High Availability Product Guide.

Fast-Wide or Ultra SCSI Cable Precautions

When connecting Symmetrix Fast-Wide SCSI or Ultra SCSI channels to host channels it is important to know Symmetrix Fast-Wide SCSI hardware components and their channel designations.

Each Fast-Wide SCSI director occupies one slot on the Symmetrix 3330/5330 backplane. Each director interfaces to the host channels via a SCSI adapter connected to the opposite side of the backplane.

The Fast-Wide or Ultra SCSI director contains two advanced microprocessors. Each microprocessor has two wide-differential SCSI channels. Figure 51 illustrates this interface and the channel designations.

When connecting the Symmetrix SCSI cables to the host channels, notice that the "A" processor channels are on the bottom and the "B" processor channels are on the top.


D

Figure 51. Fast-Wide SCSI or Ultra SCSI Director Channel Designations

AdditionalPrecautions

Observe the following precautions when connecting SCSI cables to the Symmetrix SCSI channel interface connectors:

• Use the shortest cabling possible between the Symmetrix unit and the host.

• Always check for bent pins on the SCSI cables before connecting them. The SCSI cable pins bend very easily.

• Always attach SCSI cables to their connectors straight on to minimize the chance of bending pins.

• The pin shroud on the SCSI cable ends deforms easily. Do not to drop cable ends or bang them against objects.

SymmetrixOperator Panel

Designations

HOSTCHANNELS

PhysicalChannel

Designations

A

B

A

B

Syst

emBu

s*

a

b b Processor

Ultra-FW-SCSI, or FW-SCSIFour-Port, Dual-Processor, Channel Director

ADAPTER DIRECTOR

b/A SA-05b/A*, b Processor, Port A

b/B SA-05b/B*, b Processor, Port B

a/A SA-05a/A*, a Processor, Port A

a/B SA-05a/B*, a Processor, Port Ba Processor

*Note: Odd numbered directors connect to System Bus X.Even numbered directors connect to System Bus Y.


• When attaching the SCSI cable to the connector on the SCSI adapter in the Symmetrix unit, remember to fasten the screws on the connector to ensure a secure connection.

• When connecting to hosts with differential Fast-Wide SCSI interfaces, do not allow the cable length to exceed 82 feet (25 m).

• When connecting to hosts with Ultra SCSI interfaces, do not allow the cable length to exceed 62 feet (19 m).

• Fibre Channel interfaces extend connectivity up to a maximum of 1600 feet (500 meters).


Glossary

G

This glossary contains terms related to disk storage subsystems. Many of these terms are used in this manual.

AAlternate Track A track designated to contain data in place of a

defective primary track. See also Primary Track.

Actuator A set of access arms and their attached read/write heads, which move as an independent component within a head and disk assembly (HDA).

Adapter Card that provides the physical interface between the director and disk devices (dual-initiator) or director and host channels (Bus & Tag adapter, serial adapter, or SCSI adapter.)

ADT Automatic Diagnostic Test.

ANSI American National Standards Institute. A standards-setting, non-government organization which develops and publishes standards for voluntary use in the USA.

AsynchronousTransmission

A handshaking protocol that requires each byte be requested and acknowledged before the transmission of the next byte begins.

235

BBackplane Card that accommodates the director, cache, and

adapter cards.

Bit The smallest unit of computer memory. A bit can hold a value of 0 or 1.

Business ContinuanceVolumes (BCVs)

A standard Symmetrix device with special attributes that allow it to independently support applications and processes, such as backup operations, restore operations, Decision Support operations, and application testing. BCV devices are available through the EMC TimeFinder software.

Byte Any 8-bit unit of data storage.

CCache Random access electronic storage used to retain

frequently used data for faster access by the channel.

Cache Slot Unit of cache equivalent to one track.

Campus Solution An SRDF solution that uses combinations of multimode LED fiber, single-mode laser fiber, ESCON directors, and ESCON repeaters to provide a link distance of up to 60 km. This solution typically uses a real-time (synchronous) operational mode for its remote mirroring technique. An asynchronous (journaling) mode is optional.

CCOPY Concurrent Copy Facility used on IBM DASD. See also SBRF.

Channel Director The component in the Symmetrix subsystem that interfaces between the host channels and data storage. It transfers data between the channel and cache.

236 Glossary

G

Command DescriptorBlock (CDB)

The structure used to communicate commands from an initiator to a target. This structure may be 6 bytes, 10 bytes, or 12 bytes in size.

Controller ID Controller identification number of the director the disks are channeled to for EREP usage. There is only one controller ID for Symmetrix.

Count-Key-Data(CKD)

A data recording format employing self-defining record formats in which each record is represented by a count area that identifies the record and specifies its format, an optional key area that may be used to identify the data area contents, and a data area that contains the user data for the record. CKD can also refer to a set of channel commands that are accepted by a device that employs the CKD recording format.

DDASD Direct access storage device.

Data Availability Access to user data at all times by the application.

Delayed Fast Write There is no room in cache for the data presented by the write operation. Therefore, the write is delayed until there is room in cache.

Destage The asynchronous write of new or updated data from cache to disk device.

Device A uniquely addressable part of the Symmetrix subsystem that consists of a set of access arms, the associated disk surfaces, and the electronic circuitry required to locate, read, and write data. See also Volume.

Device Address The hexadecimal value that uniquely defines a physical I/O device on a channel path in an MVS environment. See also Unit Address.

Glossary 237

Device Form Factor Refers to the physical size and shape of a device. Example: The 18 GB disk device has a 3.5-inch Form Factor.

Device Number The value that logically identifies a disk device in a string.

Device SupportFacilities program

(ICKDSF)

A program used to initialize Symmetrix at installation and provide media maintenance.

Diagnostics System level tests or firmware designed to inspect, detect, and correct failing components. These tests are comprehensive and self-invoking.

Differential Interface An electrical signal configuration that uses a pair of lines for transfer. This configuration (as compared to a single-ended interface) has a higher tolerance for common-mode noise and little crosstalk when used with twisted pair cables. It supports cables lengths to 25 meters (82 feet). See also Single-ended Interface.

Director The component in the Symmetrix subsystem that allows Symmetrix to transfer data between the host channels and disk devices. See also Channel Director and Disk Director.

Disk Director The component in the Symmetrix subsystem that interfaces between cache and the disk devices.

DSF See Device Support Facilities program.

DMA Direct Memory Access.

Dual-Initiator A Symmetrix feature that automatically creates a backup data path to the disk devices serviced directly by a disk director, if that disk director or the disk management hardware for those devices fails.

Dynamic PathReconnect (DPR)

A function that allows disconnected I/O operations with Symmetrix to reconnect over any available channel path rather than be limited to the one on

238 Glossary

G

which the I/O operation was started. This function is available only on System 370/XA, System 370/ESA, and System 390/ESA systems.

Dynamic Sparing A Symmetrix feature that automatically transfers data from a failing disk device to an available spare disk device without affecting data availability. This feature supports all devices in the Symmetrix subsystem and is used with Mirroring, RAID-S, and SRDF options.

EEMC TimeFinder EMC TimeFinder is a business continuance solution

that makes copies of data on standard Symmetrix devices called Business Continuance Volumes (BCVs). These BCVs, accessible through a separate host address, can be used by any host for backup or any other operation that requires a copy of an existing data volume. TimeFinder is available for the UNIX, Windows NT, and MVS operating systems.

EPO Emergency Power Off.

EREP program The program that formats and prepares reports from the data contained in the Error Recording Data Set (ERDS).

Error Verification The process of reading, checking the error correction bits, and writing corrected data back to the source.

ESCON Enterprise Systems Connection.

ESCON Director Device that provides a dynamic switching function and extended link path lengths (with XDF capability) when attaching an ESCON channel to a Symmetrix serial channel interface.

Glossary 239

ESP Enterprise Storage Platform. Symmetrix ESP is a functional enhancement that allows simultaneous storage and access of mainframe data and open systems data on the same Symmetrix 3330/5330 system.

FFast SCSI A synchronous transmission rate defined to be

between 5 MHz and 10 MHz.

Fast Write In Symmetrix, a write operation at cache speed that does not require immediate transfer of data to disk. The data is written directly to cache and is available for later destaging.

FBA Fixed Block Architecture. Disk device data storage format using fixed size data blocks.

FDRSOS Fast Dump Restore Safeguard Open Storage. FDRSOS is a storage management software option from Innovation Data Processing that provides high speed, full volume backup and restore of open systems volumes to mainframe tape or disk storage. FDRSOS runs under MVS XA, ESA, and OS/390 operating systems with a Symmetrix system.

Field ReplaceableUnit (FRU)

A component that is replaced or added by service personnel as a single entity.

Fibre Channel A high-speed serial interface capable of data transfer rates of up to 100 MB/sec.

Frame Data packet format in an ESCON environment.

FWD SCSI Fast-Wide Differential SCSI (Small Computer Systems Interface).

240 Glossary

G

GGigabyte (GB) 109 bytes.

The GB2 value is based on the convention: 1 GB = 1024x1024x1024 bytes. The GB10 value is based on the convention: 1 GB = 1000x1000x1000 bytes. Although these values are expressed differently, their values are equivalent.

Group The physical disks related to each other for common parity protection when implementing the RAID-S option.

HHACMP High Availability Clustered Multiprocessing. IBM’s

cluster system developed by CLAM Associates.

Head and DiskAssembly (HDA)

A field replaceable unit in the Symmetrix subsystem containing the disk and actuator.

Home Address (HA) The first field on a CKD track that identifies the track and defines its operational status. The home address is written after the index point on each track.

Hyper-VolumeExtension

The ability to define more than one logical volume on a single physical disk device making use of its full formatted capacity. These logical volumes are user-selectable in size. The minimum volume size is one cylinder and the maximum size depends on the disk device capacity and the emulation mode selected.

IICKDSF See Device Support Facilities program.

ICDA Integrated Cached Disk Array.

Glossary 241

Identifier (ID) A sequence of bits or characters that identifies a program, device, controller, or system.

IML Initial Microcode Program Loading.

Index Marker Indicates the physical beginning and end of a track.

Index Point The reference point on a disk surface that determines the start of a track.

IOCP Input/Output Configuration Program.

I/O Device An addressable input/output unit, such as a disk device.

IPL Initial Program Loading.

KKilobyte (K) 1,024 bytes.

LLeast Recently Used

Algorithm (LRU)The algorithm used to identify and make available the cache space by removing the least recently used data.

Logical Unit A physical or virtual device addressable through a target. A physical device can have more than one logical unit.

Logical Unit Number(LUN)

An encoded three-bit identifier for the logical unit of a SCSI device.

Logical Volume A user-defined storage device. In the Symmetrix subsystem, the user can define a physical disk device as one to eight logical volumes.

Logical VolumeManager (LVM)

Host software responsible for management of the disk subsystems. Interaction with the LVM is done via GUI or via stand-alone commands.

242 Glossary

G

Long Miss Requested data is not in cache and is not in the process of being fetched.

LongitudeRedundancy Code

(LRC)

Exclusive OR (XOR) of the accumulated bytes in the data record.

LPath Logical Path. Mainframe system function that allows different operating systems to run concurrently in separate logical partitions.

MMedia The disk surface on which data is stored.

Megabyte (MB) The MB2 value is based on the convention: 1 MB = 1024x1024 bytes.The MB10 value is based on the convention: 1 MB = 1000x1000 bytes.Although these values are expressed differently, their values are equivalent.

Meta device A group of components (physical partitions) accessed as a single logical device through concatenating, striping, mirroring, logging the physical devices, or setting up RAID devices.

MII Machine Initiated Interrupt.

Mirroring The Symmetrix option that maintains two identical copies of a designated volume on separate disks. Each volume automatically updates during a write operation. If one disk device fails, Symmetrix automatically uses the other disk device.

Mirrored Pair A logical volume with all data recorded twice, once on each of two different physical devices.

MVS Multiple Virtual Storage (mainframe systems only).

Glossary 243

PPage Several commands use regular parameter structures

that are referred to as pages. These pages are identified with a value known as a page code.

Partitioned Data Set(PDS) Assist

An IBM feature for 3990 Model 6 and 3990 Model 3 with Extended Platform units. PDS Assist improves performance on large, heavily-used partitioned data sets by modifying the directory search process.

Physical Partition (PP) A physical partition is the smallest unit of disk space that can be allocated in a volume group in an AIX environment. Any disk space allocated is an integral number of physical partitions. By default, a PP is 4 MB in size.

Physical ID Physical identification number of the Symmetrix director for EREP usage. This value automatically increments by one for each director installed in Symmetrix. This number must be unique in the mainframe system. It should be an even number. This number is referred to as the SCU_ID.

Primary Track The original track on which data is stored. See also Alternate Track.

Promotion The process of moving data from a track on the disk device to cache slot.

RRank The logical volumes on a disk which are related to

each other for common parity protection. A single RAID-S group can contain multiple ranks.

Read Hit Data requested by the read operation is in cache.

Read Miss Data requested by the read operation is not in cache.

Reconnect The function that occurs when a target selects an initiator to continue an operation after a disconnect.

244 Glossary

G

Glossary 245

Reconnection A reconnection exists from the assertion of the BSY signal in a RESELECTION phase until the next BUS FREE phase occurs. A reconnection can only occur between a target and an initiator.

Record Zero The first record after the home address.

Reselect The function that occurs when a target disconnects from an initiator in order to perform a time-consuming function and, then after performing that function, reestablishes the connection.

Reserved The term used for bits, bytes, fields, and code values that are set aside for future standardization.

SSBRF Symmetrix Backup/Restore Facility. Used in

conjunction with IBM’s Concurrent Copy facility.

SCSI Small Computer System Interface.

SCSI Adapter A circuit board used to interface the SCSI bus with an internal bus. Used in this manual to identify the Symmetrix SCSI Adapter that interfaces the SCSI bus from the host(s) to the Symmetrix SCSI Channel Director. Symmetrix SCSI Adapters, located in the rear card cages, have four SCSI connectors for attaching cables from the hosts(s).

SCSI Address The octal representation of the unique address (0-7) assigned to a SCSI device. This address, consisting of a target ID and LUN, or initiator ID and LUN, would normally be assigned and set in the SCSI device during system installation.

SCSI Device A host computer adapter or peripheral controller or intelligent peripheral that can be attached to the SCSI bus.

SCSI Director Card in the Symmetrix subsystem that provides the physical interface between the disk director and the disk devices.

SCSI ID The bit significant representation of the SCSI address referring to one of the signal lines DB(7-0).

SCU_ID For 3880 storage control emulations, this value uniquely identifies the storage director without respect to its selection address. It identifies to the host system, via the EREP, the director detecting the failing subsystem component. This value automatically increments by one for each director installed. The SCU_ID must be a unique number in the host system. It should be an even number and start on a zero boundary.

SDMS Symmetrix Data Migration Service allows continuous business operations and continuous data availability while data is automatically migrated from existing DASD to Symmetrix 5000 systems.

Serial Channel ESCON channel.

Short Miss Requested data is not in cache, but is in the process of being fetched.

Single-endedInterface

An electrical signal configuration that uses a single line for each signal and references a ground path common to the other signal lines. The single-ended configuration is susceptible to common mode noise and has a maximum cable length of 6 meters. See also Differential Interface.

SIO Start I/O.

SRDF Symmetrix Remote Data Facility. SRDF consists of the microcode and hardware required to support Symmetrix remote mirroring.

SSID For 3990 storage control emulations, this value identifies the physical components of a logical DASD subsystem. The SSID must be a unique number in the host system. It should be an even number and start on a zero boundary.

246 Glossary

G

Stage The process of writing data from a disk device to cache.

Storage Control Unit(SCU)

The component in the Symmetrix subsystem that connects Symmetrix to the host channels. It performs channel commands and communicates with the disk directors and cache. See also Channel Director.

Striping The process of segmenting logically sequential data and writing the segments to multiple physical disk devices.

SynchronousTransmission

A timing protocol that uses a master clock with a clock period and allowable offset that holds the sending and receiving devices in the desired phase relationship.

TTarget A SCSI device that performs an operation requested

by an initiator.

Target ID See SCSI ID.

Terabyte The TB2 value is based on the convention: 1 TB = 1024x1024x1024x1024 bytes. The TB10 value is based on the convention: 1 TB = 1000x1000x1000x1000 bytes. Although these values are expressed differently, their values are equivalent.

UUnit Address The hexadecimal value that uniquely defines a

physical I/O device on a channel path in an MVS environment. See also Device Address.

UNIX UNIX is an interactive, multi-tasking, multi-user operating system. UNIX is written in “C” language.

There are three types of UNIX files: directories, data files, and special files. A directory is a file containing

Glossary 247

certain information about another file. A directory contained within another directory is a sub-directory.

The two most common types of UNIX are BSD (Berkeley Software Distribution) and System VR4 (developed by AT&T). Most UNIX systems are a “mix” of both types.

VVolume A general term referring to a storage device. In the

Symmetrix subsystem, a volume corresponds to single disk device.

248 Glossary

I

Index

Numerics3330/5330 Storage Capacities

187– 1893330-18/5330-18 device capacities

5– 63330-9/5330-9 device capacities 6– 73390 DASD

track format 55

AActive/Ready LED 50Adaptive Copy mode 24, 154Address mark 56AS/400 disk devices

cylinders, maximum per logical volume 95

AS/400 hosts 95Automatic Failover Module for HP

MetroCluster 28Availability features 17

dynamic sparing 155– 162mirroring 135– 137multi-port volume access (SCSI)

115Availability guidelines

dual-initiator 118dynamic sparing 121mirroring 120SRDF option 120

BBackplane 47Battery 47

Battery backup 123power failure on mainframe

channels 123power failure on open systems

channels 124Block capacity 95Bus & Tag

cables 65connector panel 47

CCabling requirements 212Cache 90

5330/3330 maximum memory 63

bandwidth 63basic operation 83error correction and verification

133fast write ceiling 86host cache use 74management 75– 77prefetch algorithm 76

Cache RMF Reporter 113Caching techniques 78Card cage 47Channel

cable length 93interfaces 11, 61, 63SCSI termination 232

Channel connections 65– 71Fibre 61parallel 65– 66precautions 232serial 67– 68

Index 249

Channel directorFibre 61FWD SCSI 61operator panel 49– 50parallel 62serial 62SRDF Remote Link 62Ultra SCSI 61

Channel extenders 68– 70ESCON-to-parallel converter 69

Channel speed 93Channel status bits 183Command connect time 80Componenst,non-disruptive

replacement 128Component descriptions 46– 64Component design 122Connect time 79Cooling module 47Count-key-data (CKD) format 55Cylinders

per logical volume for split physical devices 97

DDASD Data Transfer Summary 174Data

reliability and availability features 122– 130

transfer rateSRDF Remote Link Director

63Data and command formats 55– 57

data records 56home address (HA) 56index marker 56record zero (RO) 56track capacity 57track format 55

Data check error 164, 165Data connect time 80

Data integrity protection 131– 133cache error correction and error

verification 133cache error correction and

verification 133disk error correction and

verification 132error checking and correction

131– 132error verification 119periodic system check tests 119

Data protection options 134– 162dynamic sparing 134, 155– 162mirroring, mission

critical/business critical 119

RAID-S, business online 119SRDF 120

Data recoverydynamic sparing 155– 157dynamic sparing with mirrored

pairs 158– 159dynamic sparing with RAID-S

volumes 159– 162dynamic sparing with SRDF 162RAID-S 148– 152

Data storagedata access patterns 109disk emulation 54

Data transfer ratesFibre Channel 61parallel channel 62SCSI 61serial channel 62Ultra SCSI 61

DataReach 31Defective tracks 167Delayed fast write operation 86Determining error source 176Differential adapter 232

250 Index

I

Directors 62, 63disk 63Fast-Wide SCSI channel 61Fibre Channel 61parallel channel 62serial channel 62Ultra SCSI channel 61

Disconnect time 79, 80Disk devices 47, 51

18 GB capacities 518 GB cylinders/logical volume

1919 GB capacities 69 GB cylinders/logical volume

1919 GB/logical volume 193capacity for hyper-volumes 103emulation types 54error correction and verification

132Logical-to-physical volume

relationships 96RPS miss elimination 83

Disk director 63cache error verification 133dual-initiator operation 124operator panel 49

Disk emulation 54, 57Disk Error Correction 132Disk Error Verification 132Domestic shipments 211Dual copy 21Dual-initiator 124– 128

advantages 128availability guidelines 118failure levels 126fencing mechanisms 124illustrated 125

Dynamic Mirror Service Policy (DMSP) 92

Dynamic Path Reconnection (DPR) 87

Dynamic reconfiguration 130Dynamic sparing 121, 155– 162

advantages 157availability guidelines 121

EECC 132EDM (EMC Data Manager) 41EDM Symmetrix Connect 42EMC CopyPoint for AS/400 28EMC Customer Support Center 18EMC Data Manager 41EMC InfoMover 30EMC PowerPath 39EMC Solutions Enabler Overview 37EMC Solutions Enabler SYMCLI Base

Component 37EMC Solutions Enabler SYMCLI SRDF

Component 38EMC Solutions Enabler SYMCLI

TimeFinder Component 39Emergency power off procedure 205Enterprise Storage Platform (ESP) 30Environmental data 196Environmental specifications 212EPO switch 202Equipment checks 164, 167EREP file 165EREP reports 173– 174

DASD Data Transfer Summary 174

Subsystem Exception DASD 174System Error Summary (part 2)

174Error checking and correction

cache 133disk 132ECC 132parity 132

Error code 169Error detection 132, 175Error handling

detecting the error 175determining error source 176

Error recoverability 165– 167Error reporting 168– 174

EREP reports 173– 174Error verification 119

Index 251

Errors 164– 167permanent 164temporary 164

ESCON channelsattaching to parallel interfaces 66

ESCON converter 66ESCON director 69ESCON-to parallel converter 69ESP (Enterprise Storage Platform) 30Event messages 170Extended count-key-data (ECKD) 55Extended cylinder addressing 101,

102External modem 47

FFast write ceiling 86, 90Fast write operation 90Fast-Wide SCSI channel director 61FDR Instant Backup 43FDRSOS (Fast Dump Restore Safeguard

Open Storage) option 42Fiber optic cables 67Fibre Channel

attachments 71director 61SCSI to Fibre Channel migration

130supported single hosts 14

Floor tile cutout 214

HHigh availability

multi-port volume access 115Home Address (HA) 56Host Data Compression 21Host Integration 10

supported hosts 11

HostsAS/400 95PC servers 95supported cluster hosts 15supported Fast-Wide SCSI single

12supported Fibre Channel single

14supported Ultra SCSI single 13UNIX 95

HP OpenView Omniback II 43Hyper-volume extension

extended cylinder addressing 102

mainframe 101– 106split-volume capability 102

Hyper-volumesmainframe systems 101– 106multiple logical volumes per

physical device 96open systems 95– 100

II/O operations

delayed fast write 86overview 79– 82read miss 84

I/O response timecommand connect time (open

systems) 80connect time (mainframe) 79data connect time (open

systems) 80disconnect time (mainframe) 79disconnect time (open systems)

80mainframe environment 79open systems environment 80pend time (mainframe) 79queuing time (mainframe) 79queuing time (open systems) 80

ICDA operation 74– 78Index marker 56Installation planning 210– 234Integrated cached disk array (ICDA)

74

252 Index

I

International shipments 211

LLegato NetWorker for EMC

Symmetrix 43Logical-to-physical volume

relationships 96LRC

calculation 132LRU algorithm 111

MMain components 46– 47

backplane 47battery subsystem 47block diagram 48bus & tag connector panel 47card cage 47cooling modules 47disk devices 47dual power cords 48Ethernet hub 47service processor 47

Mainframe systemsidentifying storage requirements

109performance guidelines 109– 111

Measuring performanceusing Cache RMF Reporter 113using RMF 112using VM/Monitor and VMPRF

113Microcode

non-disruptive upgrade 129Mirroring 135– 137

advantages 137availability guidelines 120

Mixed track geometries 55Monitoring performance

in mainframe environment 112setting objectives 112

Multimode cables 67Multi-Path Lock Facility (MPLF) 19Multi-Subsystem Imaging 20

NND-SDMS 26Non-disruptive component

replacement 128Non-disruptive microcode upgrade

129Non-Disruptive Symmetrix Data

Migration Service 26

OOpen systems

optimizing performance 107– 108

Open systems data 30Operating systems

mainframe 10Operator messages 171Operator panel 49– 50

channel director 49– 50disk director 49enable/disable switches 50functions 49

Overrun error 164, 167

PParallel channel director 62

interface connections 65– 66Parallel processing 91Parity detection method 132Partitioned Data Set (PDS) Search

Assist 21PC server hosts 95PDS Assist 21Pend time 79Performance

guidelines for storage devices 110

monitoring in mainframe environment 112

objectives in mainframe environment 112

Index 253

Performance features 16, 90cache 90channel speed 93fast write capabilities 90mainframe systems hyper-volume

extension 101– 106multiple channel directors 91multi-port volume access 115open systems hyper-volume

extension 95– 98parallel processing 91PermaCache 93RPS Miss Elimination 92

PermaCache 93Permanent errors 164Phone multiplexer 22Physical data 194Planning overview 210– 215Power and cooling data 197Power LED 50Power On/Off procedures

emergency power off 205powering down 204powering up 202

Power requirements 199, 211Power subsystem 122Power switch

AC power switch location 202Power switch EPO switch location

202Prefetch algorithm 76Program check error 164

QQueuing time 79, 80

RRAID-S 138– 153

advantages 152data recovery 148– 152data recovery with HVE 151data volumes 140, 141, 151disk devices 139modes of operation 143parity volumes 140, 142, 151rank 141, 143read requests on a failing

volume 149reading data in a RAID-S group

147rebuilding parity 151regenerating data 151with Hyper-Volume Extension

142– 143write requests on a failing

volume 149writing data in a RAID-S group

145Read miss operation 84Read operations 83– 84Reassigning defective tracks 166Record Zero (R0) 56Reliability and availability features

122– 130battery backup system 123dual-initiator 124– 128dynamic reconfiguration 130non-disruptive component

replacement 128non-disruptive microcode

upgrades 129online SCSI to Fibre Channel

migration 130redundant power subsystem 122

Reliability featuresdynamic sparing 155– 162mirroring 135– 137redundant architecture 122

Remote support 215Resource Measurement Facility

(RMF) 112, 113

254 Index

I

RPS Miss Elimination 92

SSCSI hardware components 70– 71SCSI terminators 232SCSI to Fibre Channel Migration,

Online 130SDRF FarPoint 25Segmented data buffer(ing) 92Semi-synchronous data copying 24,

154Semi-synchronous mode 24, 154Sequential data access patterns 76Sequential Data Striping 20Serial channel director 62

interface connections 67– 68Service Alert Messages 171

error codes 169events 170

Service processor 18, 47Serviceability features 18Single-mode cables 67Soft error thresholds 132Software options

AFM for HP MetroCluster 28DataReach 31EMC CopyPoint for AS/400 28EMC InfoMover 30EMC PowerPath 39EMC Solutions Enabler 37EMC TimeFinder 27FDRSOS 42Legato NetWorker for EMC

Symmetrix 43Symmetrix ESP 30

Space requirements 213Specifications

environmental data 196physical data 194– 195power and cooling data 197power requirements 199storage control 186

Split-volume option 102– 106

SRDF 24, 154error messages 169Semi-synchronous data copying

154Semi-synchronous mode 154Synchronous mode 154T3/E3 link 154Uni-directional configuration

154SRDF Host Component 35SRDF Remote Link Director 62SSID 20SSOM 27Storage control 186Storage devices

data access patterns in a mainframe system 109

Storage devices, choosing 110Storage directors 91Subsystem Exception DASD 174Symmetix Manager - Base

Component 33

Index 255

Symmetrixavailability features 17block diagram 48Channel interfaces 62channel interfaces 11, 61, 62,

63, 232data integrity protection

131– 133dual-initiator 124– 128dynamic sparing 155– 162host data compression 21I/O operations 79– 87installation planning 210– 234internal components 46mirroring 135– 137MPLF 19operator panel 49– 50PDS Assist 21performance features 16PermaCache 93physical specifications 211powering down 204powering up 202product introduction 2RAID-S option 138– 153sequential data striping 20serviceability features 18software options 23– 44specifications 185– 199split-volume option 102– 106SRDF option 154

Symmetrix Backup/Restore Facility (SBRF) 19

Symmetrix Data Migration Service (SDMS) 26

Symmetrix Enterprise Storage Platform (ESP) 30

Symmetrix Manager - SDDR Component 36

Symmetrix Manager - SRDF Component 34

Symmetrix Manager - TimeFinder Component 36

Symmetrix Manager Workload Analyzer 34

Symmetrix reliability and availability features 118

Symmetrix Remote Data Facility 154Symmetrix Remote Data Facility

(SRDF) 24– 25Symmetrix to Symmetrix Open Systems

Migration 27Symmetrix work sheets 223– 231Synchronous data copying 24, 154Synchronous mode 24, 154System check error 164System check tests 119System Error Summary (Part 2) 174

TT3/E3 link 24, 154Temporary errors 164TimeFinder 27TimeFinder Direct Connect 41Track capacity 57Track format 55Transportation and delivery

guidelines 211Types of errors 164– 167

data check 164equipment checks 164overrun 164system or program check 164

UUltra SCSI channel director 61Uni-directional configuration 24,

154Unit status bits 182UNIX hosts 95

VVM Performance Planning Facility

(VMPPF) 113VM/Monitor 113

WWorkload Analyzer 34Write operations 85– 86

256 Index

Sales and Service Locations

CorporateHeadquarters

EMC CorporationHopkinton, Massachusetts01748-9103 U.S.A.508-435-10001-800-424-EMC2

Asia PacificHeadquarters

EMC Japan K.K.P.O. Box 323Shinjuku-Mitsui Bldg., 42F1-1, Nishi-Shinjuku2-chome Shinjuku-kuTokyo 163-04 JAPANTel: 81-3-3345-3211Fax: 81-3-3345-3221

North AmericanSales and Service

Locations

Atlanta, GA 404-705-4750Baltimore, MD 410-850-4324Bethesda, MD 301-530-0091Boston, MA 617-449-8100Charlotte, NC 704-521-9773Cheshire, CT 203-271-2933Chicago, IL 708-390-8800Cincinnati, OH 513-745-0300Cleveland, OH 216-573-1162Columbus, OH 614-436-3900Dallas, TX 214-233-5676Englewood, CO 303-770-8915Farmington Hills, Ml 313-553-4810Ft. Lauderdale, FL 305-776-3622Greensboro, NC 910-665-1077Houston, TX 713-621-9800Indianapolis, IN 317-577-9766Inglewood, CA 310-364-1222

257

Irvine, CA 714-833-1442Lenexa, KS 913-469-9292Long Island, NY 516-393-5045Minneapolis, MN 612-835-1994Montreal, Quebec 514-856-6166Nashville, TN 615-781-4394New York City, NY 212-564-6866Ottawa, Ontario 613-233-0111Orlando, FL 407-855-4087Phoenix, AZ 602-955-0702Philadelphia, PA 610-834-7740Pittsburgh, PA 412-922-5222Portland, OR 503-293-8450Raleigh, NC 919-420-0405Rochester, NY 716-387-0970Salt Lake City, UT 801-532-1454San Diego, CA 619-576-1880San Francisco, CA 415-871-1970Seattle, WA 206-365-2254Southington, CT 860-620-6730Springfield, NJ 201-467-7979St. Louis, MO 314-469-9005Tampa, FL 813-282-0274Toronto, Ontario 905-206-1580Tulsa, OK 918-663-2255Vancouver, BC 604-270-1657Washington, D.C. 703-893-8400

International SalesLocations

Berlin, Germany (49) 30 25 49 31 86Bologna, Italy (39) 51 522579Brescia, Italy (39) 30 2421791Brussels, Belgium (32) 2 725 74 25Cape Town, South Africa (27) 21 686 1430Dublin, Ireland (353) 1 475 4172Durban, South Africa (27) 31 83 6611Dusseldorf, Germany (49) 2131 9191 0Frankfurt, Germany (49) 6196 4 72 80Hamburg, Germany (49) 4069 69 610Hong Kong, Taikooshing (852) 2839 9600Johannesburg, South Africa (27) 11 807 5300Leatherhead, Surrey, UK (44) 1372 36 0000

258 Sales and Service Locations

Lyon, France (33) 7 860 1330Marseille, France (33) 4292 2549Melbourne, Australia (61) 3 653 9519Milan, Italy (39) 2 409081Munich, Germany (49) 89 14 31 320Nagoya, Japan (81) 52 223 1900Newton Le Willows, Merseyside, UK

(44) 1942 275 511Nieuwegein, Netherlands (31) 03 6055777Nuernberg, Germany (49) 911 2379260Osaka, Japan (81) 6 373 8300Padua, Italy (39) 49 8235853Paris, France (33) 1 3082 5100Pretoria, South Africa (27) 12 663 6635Rome, Italy (39) 6 8552116Schlieren, Switzerland (411) 743 4949Seoul, Korea (82) 2 539 4455Singapore (65) 338 9265Stuttgart, Germany (49) 7152 979340Sydney, Australia (61) 2 922 7888Toulouse, France (33) 6131 6262Turin, Italy (39) 11 746527

Sales and Service Locations 259

260 Sales and Service Locations

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