Contents

Title and Copyright Information

List of Examples

List of Figures

List of Tables

Send Us Your Comments

Preface

Audience

Organization

Related Documentation

Conventions

Documentation Accessibility

What's New in Data Guard?

Oracle9i Release 1 (9.0.1) New Features in Data Guard

Oracle8i New Features in Data Guard

Part I Concepts and Administration

1 Oracle9i Data Guard Concepts

1.1 Oracle9i Data Guard Overview

1.2 Operational Requirements

1.3 Oracle Data Guard Architecture

1.4 Log Transport Services

1.5 Log Apply Services

1.6 Role Management Services

1.7 Physical Standby Process Architecture

1.8 Data Guard Environments

1.8.1 Typical Two-Site Data Guard Environment

1.8.2 Data Divergence and Data Loss

1.8.3 Primary Database Protection Modes Overview

1.8.4 Standby Database No-Data-Loss Failover

1.8.5 Standby Database Data-Loss Failover

1.8.6 Primary Database Protection Modes Description

1.8.7 Data Divergence and Data Loss Summary

1.8.8 Delayed Standby

1.9 Standby Database Operational Modes

1.10 Database Roles

1.11 Failover and Switchover

1.11.1 Database Switchover

1.11.2 Database Switchback

1.12 Data Guard Interfaces

1.13 Standby Database Creation

2 Creating the Standby Database Environment

2.1 Considerations for Creating the Standby Database Environment

2.1.1 Number of Standby Databases

2.1.2 Typical Modes for a Standby Database in the Data Guard Environment

2.1.3 Method of Archiving Redo Logs to the Standby Site

2.1.4 Method of Applying Redo Logs on the Standby Site

2.1.5 Location and Directory Structure of Primary and Standby Sites

2.1.6 Advantages of Using Multiple Standby Databases

2.2 Creating a Standby Database: Basic Tasks

2.3 Creating the Standby Database Files

2.3.1 Using Backups for Standby Creation

2.3.2 Creating the Standby Datafiles

2.3.3 Creating the Standby Control File

2.3.4 Copying Files to the Standby Site

2.4 Creating the Standby Initialization Parameter File

3 Log Transport Services

3.1 Introduction to Log Transport Services

3.1.1 Background

3.1.2 Functional Overview

3.1.3 Log Transport Services Process Architecture

3.2 Log Transport Services Capabilities

3.2.1 Permission

3.2.2 Destination

3.2.3 Transmission

3.2.4 Reception

3.2.5 Failure Resolution

3.3 Log Transport Services Interfaces

3.3.1 Database Initialization Parameters

3.3.2 SQL Interface

3.4 Configuring Log Transport Services on the Primary Database

3.4.1 Configuring Log Transport Services

3.4.2 Setting Up the Log Transport Services Environment

3.5 Configuring Log Transport Services on the Standby Database

3.5.1 Configuring the Standby Initialization Parameter File

3.5.2 Transferring the Initialization Parameter File to the Standby Database

3.5.3 Setting Up the Initialization Parameter File

3.6 Log Transport Services Data Availability Modes

3.6.1 Introduction to Database Synchronization Options

3.6.2 Choosing the Appropriate Data Availability Mode

3.6.3 Configuring Log Transport Services Data Availability Modes

3.6.4 Comparing Network and Disk I/O Methods

3.7 Network Tuning for Log Transport Services

3.8 Log Transport Services Monitoring

3.8.1 Gathering Redo Log Archival Information

3.8.2 Setting Archive Tracing

4 Log Apply Services

4.1 Introduction to Log Apply Services

4.2 Process Architecture

4.3 Managed Recovery Mode

4.3.1 Starting the Standby Instance in Preparation for Recovery

4.3.2 Initiating Log Apply Services

4.3.3 Monitoring the Recovery Process

4.4 Controlling Managed Recovery Mode

4.4.1 CANCEL Control Option

4.4.2 DELAY Control Option

4.4.3 DISCONNECT Control Option

4.4.4 EXPIRE Control Option

4.4.5 FINISH Control Option

4.4.6 NEXT Control Option

4.4.7 NODELAY Control Option

4.4.8 PARALLEL Control Option

4.4.9 TIMEOUT Control Option

4.5 Archive Gap Management

4.6 Datafile Management

4.6.1 Setting the STANDBY_FILE_MANAGEMENT Initialization Parameter

4.6.2 Restrictions on ALTER DATABASE Operations

4.7 Read-Only Mode

4.7.1 Assessing Whether to Run in Read-Only Mode

4.7.2 Placing the Database in Read-Only Mode

4.8 Read-Only Mode Considerations

4.8.1 Receiving Archived Redo Logs While in Read-Only Mode

4.8.2 Sorting While in Read-Only Mode

4.8.3 Sorting Without Temporary Tablespaces

4.9 Monitoring Log Apply Services

4.9.1 Accessing the V$MANAGED_STANDBY Fixed View

4.9.2 Accessing the V$ARCHIVE_DEST_STATUS Fixed View

4.9.3 Accessing the V$ARCHIVED_LOG Fixed View

4.9.4 Accessing the V$LOG_HISTORY Fixed View

4.9.5 Setting Archive Tracing

5 Managing the Data Guard Environment

5.1 Database Roles

5.2 Database Role Transitions

5.2.1 Database Switchover

5.2.2 Database Switchback

5.2.3 Graceful Database Failover

5.2.4 Forced Database Failover

5.3 Switching Over Your Database

5.3.1 Switchover Precautions

5.3.2 Preparation for Successful Switchover

5.3.3 Switching the Primary Database Role to Standby

5.3.4 Switching the Standby Database Role to Primary

5.3.5 Multiple Standby Databases in Switchover

5.3.6 Standby Databases Not Involved in Switchover

5.3.7 Identifying Active Instances

5.3.8 Identifying Active SQL Sessions

5.3.9 Validating the Switchover Transition

5.4 Database Failover

5.4.1 Data Divergence and Data Loss

5.4.2 Primary Database Protection Modes Overview

5.4.3 Standby Database No-Data-Loss Failover

5.4.4 Standby Database Data-Loss Failover

5.4.5 Planning for Database Failover

5.4.6 Graceful Failover

5.4.7 Forced Failover

5.5 Role Transition Summary

5.6 Backing Up the Primary Database Using the Standby Database

5.7 Monitoring Events That Affect the Standby Database

5.7.1 Dynamic Performance Views (Fixed Views)

5.7.2 Monitoring the Primary and Standby Databases

5.7.3 Determining Which Logs Have Been Applied to the Standby Database

5.7.4 Determining Which Logs Have Not Been Received by the Standby Site

5.8 Responding to Events That Affect the Standby Database

5.8.1 Adding or Dropping Tablespaces and Adding or Deleting Datafiles in the Primary Database

5.8.2 Renaming Datafiles on the Primary Database

5.8.3 Adding or Deleting Redo Logs on the Primary Database

5.8.4 Resetting or Clearing Unarchived Redo Logs on the Primary Database

5.8.5 Altering the Primary Database Control File

5.8.6 Taking Datafiles in the Standby Database Offline

5.8.7 Detecting Unlogged or Unrecoverable Operations

5.8.8 Refreshing the Standby Database Control File

5.8.9 Clearing Online Redo Logs

5.9 Standby Database with an Oracle Real Application Clusters Configuration

5.9.1 Setting Up a Cross-Instance Archival Database Environment

6 Data Guard Scenarios

6.1 Scenario 1: Creating a Standby Database on the Same Site

6.1.1 Step 1: Plan the Standby Database.

6.1.2 Step 2: Create the Standby Database.

6.1.3 Step 3: Configure Oracle Net.

6.1.4 Step 4: Configure the Primary Database Parameter File.

6.1.5 Step 5: Configure the Standby Database Parameter File.

6.1.6 Step 6: Start the Standby Database in Preparation for Managed Recovery.

6.1.7 Step 7: Place the Standby Database in Managed Recovery Mode.

6.2 Scenario 2: Creating a Standby Database on a Remote Site

6.2.1 Step 1: Back Up the Primary Database Datafiles.

6.2.2 Step 2: Create the Standby Database Control File.

6.2.3 Step 3: Transfer the Datafiles and Control File to the Standby Site.

6.2.4 Step 4: Configure Oracle Net.

6.2.5 Step 5: Start the Listener on the Primary and Standby Site.

6.2.6 Step 6: Configure the Standby Initialization Parameter File.

6.2.7 Step 7: Copy the Standby Initialization Parameter File.

6.2.8 Step 8: Start the Standby Database.

6.2.9 Step 9: Configure the Primary Initialization Parameter File.

6.2.10 Step 10: Place the Standby Database in Managed Recovery Mode.

6.3 Scenario 3: Accommodating Physical Changes in the Primary Database

6.3.1 Adding a Datafile to the Primary Database

6.3.2 Renaming a Datafile in the Primary Database

6.3.3 Deleting a Datafile or Dropping a Tablespace in the Primary Database

6.3.4 Adding or Dropping Online Redo Logs

6.3.5 Altering Control Files

6.3.6 Refreshing the Standby Database Control File

6.3.7 Physical Changes That Require You to Rebuild the Standby Database

6.4 Scenario 4: Recovering After the NOLOGGING Clause Is Specified

6.5 Scenario 5: Deciding Which Standby Database to Fail Over to in a Multiple Standby Database Configuration

6.6 Scenario 6: Switching Over a Primary Database to a Standby Database

6.6.1 Step 1: End Read or Update Activity on the Primary and Standby Databases.

6.6.2 Step 2: Prepare the Primary Database for Switchover.

6.6.3 Step 3: Shut Down and Start Up the Former Primary Instance Without Mounting the Database.

6.6.4 Step 4: Mount the Former Primary Database in the Standby Database Role.

6.6.5 Step 5: Prepare the Former Standby Database to Switch to the Primary Database Role.

6.6.6 Step 6: Shut Down the Database.

6.6.7 Step 7: Start Up the Database in the Primary Role.

6.6.8 Step 8: Put the Standby Database in Managed Recovery Mode.

6.6.9 Step 9: Start Archiving Logs from the Primary Database to the Standby
Database.

6.7 Scenario 7: Configuring Client Application Failover

6.7.1 Local TNS Configuration

6.7.2 Oracle Names Server Configuration

6.7.3 Transparent Application Failover (TAF) Configuration

6.7.4 Manual Network Configuration

6.8 Scenario 8: Recovering After a Network Failure

6.8.1 Step 1: Identify the Network Failure.

6.8.2 Step 2: Prevent the Primary Database from Stalling.

6.8.3 Step 3: Archive the Current Redo Log.

6.9 Scenario 9: Re-Creating a Standby Database

6.9.1 Step 1: Create a Standby Database at the Original Primary Site.

6.9.2 Step 2: Fail Over to the Standby Database at the Original Primary Site.

6.9.3 Step 3: Create a New Standby Database at the Original Standby Site.

6.10 Scenario 10: Standby Database with No Ongoing Recovery

6.10.1 Managing a Standby Database with No Ongoing Recovery

6.10.2 Activating a Standby Database with No Ongoing Recovery

6.11 Scenario 11: Standby Database with a Time Lag

6.11.1 Creating a Standby Database with a Time Lag

6.11.2 Managing a Standby Database with a Time Lag

6.11.3 Rolling Back the Database to a Specified Time

6.11.4 Bypassing the Time Lag and Activating the Standby Database

6.12 Scenario 12: Using a Standby Database to Back Up the Primary Database

6.12.1 Step 1: Back Up the Standby Database.

6.12.2 Step 2: Restore the Backup at the Primary Site.

Part II Reference

7 Initialization Parameters

8 LOG_ARCHIVE_DEST_n Parameters Attributes

About LOG_ARCHIVE_DEST_n Parameters Attributes

AFFIRM and NOAFFIRM

ALTERNATE and NOALTERNATE

ARCH and LGWR

DELAY and NODELAY

DEPENDENCY and NODEPENDENCY

LOCATION and SERVICE

MANDATORY and OPTIONAL

MAX_FAILURE and NOMAX_FAILURE

QUOTA_SIZE and NOQUOTA_SIZE

QUOTA_USED and NOQUOTA_USED

REGISTER and NOREGISTER

REGISTER=location_format

REOPEN and NOREOPEN

SYNC and ASYNC

Attribute Compatibility for Archive Destinations

9 SQL Statements

10 Fixed Views

About Fixed Views

V$ARCHIVE_DEST

V$ARCHIVE_DEST_STATUS

V$ARCHIVE_GAP

V$ARCHIVED_LOG

V$DATABASE

V$DATAFILE

V$LOG

V$LOGFILE

V$LOG_HISTORY

V$MANAGED_STANDBY

V$STANDBY_LOG

Part III Appendixes and Glossary

A Troubleshooting the Standby Database

A.1 Problems During Standby Database Preparation

A.1.1 The Standby Archive Destination Is Not Defined Properly

A.1.2 The Standby Site Does Not Receive Logs Archived by the Primary Database

A.1.3 You Cannot Mount the Standby Database

A.2 Problems Switching Over to a Standby Database

A.2.1 Prepare to Switchover Fails

A.2.2 Startup of Second Database Fails

A.2.3 Archived Redo Logs Are Not Applied to the Standby Database After
Switchover

B Manual Recovery

B.1 Preparing a Standby Database for Manual Recovery: Basic Tasks

B.2 Placing the Standby Database in Manual Recovery Mode

B.2.1 Initiating Manual Recovery Mode

B.2.2 When Is Manual Recovery Required?

B.3 Resolving Archive Gaps Manually

B.3.1 What Causes Archive Gaps?

B.3.2 Determining Whether an Archive Gap Exists

B.3.3 Manually Transmitting the Logs in the Archive Gap to the Standby Site

B.3.4 Manually Applying the Logs in the Archive Gap to the Standby Database

B.4 Renaming Standby Files Manually

C Log Writer Asynchronous Network I/O

D Standby Database Real Application Cluster Support

Glossary

Index