Preface

This book is a database high availability reference. It describes Oracle database architectures and features as well as recommended practices that can help your business achieve high availability. It provides guidelines for choosing the appropriate high availability solution.

This preface contains these topics:

• Audience

• Documentation Accessibility

• Organization

• Related Documents

• Conventions

Audience

This book is intended for chief technology officers, information technology architects, database administrators, system administrators, network administrators, and application administrators who perform the following tasks:

• Plan data centers

• Implement data center policies

• Maintain high availability systems

• Plan and build high availability solutions

Documentation Accessibility

Our goal is to make Oracle products, services, and supporting documentation accessible, with good usability, to the disabled community. To that end, our documentation includes features that make information available to users of assistive technology. This documentation is available in HTML format, and contains markup to facilitate access by the disabled community. Standards will continue to evolve over time, and Oracle is actively engaged with other market-leading technology vendors to address technical obstacles so that our documentation can be accessible to all of our customers. For additional information, visit the Oracle Accessibility Program Web site at

http://www.oracle.com/accessibility/

Accessibility of Code Examples in Documentation

JAWS, a Windows screen reader, may not always correctly read the code examples in this document. The conventions for writing code require that closing braces should appear on an otherwise empty line; however, JAWS may not always read a line of text that consists solely of a bracket or brace.

Accessibility of Links to External Web Sites in Documentation

This documentation may contain links to Web sites of other companies or organizations that Oracle does not own or control. Oracle neither evaluates nor makes any representations regarding the accessibility of these Web sites.

Organization

This document contains:

Part I, "Getting Started"

This part provides an overview of high availability (HA) and describes the Oracle features that can be used to achieve high availability.

Chapter 1, "Overview of High Availability"

This chapter defines high availability and the need for HA architecture and practices. It describes in general terms what is necessary to achieve high availability. It gives examples of outages and their impact on businesses. It also explains the scope of the book and how to use the book.

Chapter 2, "Determining Your High Availability Requirements"

This chapter describes service level agreements and business requirements. It provides guidelines for determining whether data loss is acceptable and discusses the performance and manageability impact of HA practices.

Part II, "Oracle Database High Availability Features, Architectures, and Policies"

This part explains what business requirements influence the decision to implement a high availability solution. After the essential factors have been identified, defined, and described, the factors are used to provide guidance about choosing a high availability architecture.

Chapter 3, "Oracle Database High Availability Features"

This chapter provides high-level descriptions of Oracle HA features.

Chapter 4, "High Availability Architectures"

This chapter describes validated HA architectures.

Chapter 5, "Operational Policies for High Availability"

This chapter describes operational best practices for HA.

Part III, "Configuring a Highly Available Oracle Environment"

This part describes how to configure the high availability architectures.

Chapter 6, "System and Network Configuration"

This chapter provides recommendations for configuring the subcomponents that make up the database server tier and the network.

Chapter 7, "Oracle Configuration Best Practices"

This chapter recommends Oracle configuration and best practices for the database, Oracle Real Application Clusters, Oracle Data Guard, Maximum Availability Architecture, backup and recovery, and fast application failover.

Part IV, "Managing a Highly Available Oracle Environment"

This part describes how to manage an HA Oracle environment.

Chapter 8, "Using Oracle Enterprise Manager for Monitoring and Detection"

This chapter describes how to monitor and detect system availability. It emphasizes Oracle Enterprise Manager.

Chapter 9, "Recovering from Outages"

This chapter contains a decision matrix for determining what actions to take for specific outages.

Chapter 10, "Detailed Recovery Steps"

This chapter contains detailed steps for recovering from the outages described in Chapter 9, "Recovering from Outages".

Chapter 11, "Restoring Fault Tolerance"

This chapter describes the following types of repair: restoring failed nodes in a Real Application Cluster, restoring the standby database after a failover, restoring fault tolerance after secondary site or clusterwide scheduled outage, restoring fault tolerance after a standby database data failure, restoring fault tolerance after the production database is activated, and restoring fault tolerance after dual failures.

Appendix A, "Hardware Assisted Resilient Data (HARD) Initiative"

This appendix contains information about the Hardware Assisted Resilient Data (HARD) initiative.

Appendix B, "Database SPFILE and Oracle Net Configuration File Samples"

This appendix contains database SPFILE and Oracle Net configuration file samples.

Related Documents

For more information, see the Oracle database documentation set. These books may be of particular interest:

• Oracle Data Guard Concepts and Administration

• Oracle Real Application Clusters Deployment and Performance Guide

• Oracle Database Backup and Recovery Advanced User's Guide

• Oracle Database Administrator's Guide

• Oracle Application Server 10g High Availability Guide

Many books in the documentation set use the sample schemas of the seed database, which is installed by default when you install Oracle. Refer to Oracle Database Sample Schemas for information on how these schemas were created and how you can use them yourself.

Printed documentation is available for sale in the Oracle Store at

http://oraclestore.oracle.com/

To download free release notes, installation documentation, white papers, or other collateral, please visit the Oracle Technology Network (OTN). You must register online before using OTN; registration is free and can be done at

http://otn.oracle.com/membership/index.html

If you already have a username and password for OTN, then you can go directly to the documentation section of the OTN Web site at

http://otn.oracle.com/documentation/index.html

Conventions

This section describes the conventions used in the text and code examples of this documentation set. It describes:

• Conventions in Text

• Conventions in Code Examples

• Conventions for Windows Operating Systems

Conventions in Text

We use various conventions in text to help you more quickly identify special terms. The following table describes those conventions and provides examples of their use.

Conventions in Code Examples

Code examples illustrate SQL, PL/SQL, SQL*Plus, or other command-line statements. They are displayed in a monospace (fixed-width) font and separated from normal text as shown in this example:

SELECT username FROM dba_users WHERE username = 'MIGRATE';

The following table describes typographic conventions used in code examples and provides examples of their use.

[ ]

DECIMAL (digits [ , precision ])

{ }

{ENABLE | DISABLE}

|

{ENABLE | DISABLE}
[COMPRESS | NOCOMPRESS]

...

CREATE TABLE ... AS subquery;

SELECT col1, col2, ... , coln FROM employees;

acctbal NUMBER(11,2);
acct    CONSTANT NUMBER(4) := 3;

Italics

CONNECT SYSTEM/system_password
DB_NAME = database_name

UPPERCASE

SELECT last_name, employee_id FROM employees;
SELECT * FROM USER_TABLES;
DROP TABLE hr.employees;

lowercase

SELECT last_name, employee_id FROM employees;
sqlplus hr/hr
CREATE USER mjones IDENTIFIED BY ty3MU9;

Conventions for Windows Operating Systems

The following table describes conventions for Windows operating systems and provides examples of their use.

C:\oracle\oradata>

C:\>exp HR/HR TABLES=employees QUERY=\"WHERE job_id='SA_REP' and salary<8000\"

HOME_NAME

C:\> net start OracleHOME_NAMETNSListener