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Preface

1 Standby Database Concepts

What Is a Standby Database?

Configuration Options

Advantages and Disadvantages

Compatibility and Operational Requirements

Concepts and Terminology

Standby Database Modes

Manual Recovery Mode

Managed Recovery Mode

Read-Only Mode

Failover to a Standby Database

Consequences of Failover

Testing the Standby Database Without Performing Failover

Re-Creating the Original Primary Database After Failover

Standby Database Life Cycle

Standby Database Creation

Manual Recovery Using Logs in the Gap Sequence

Managed Recovery and Read-Only Access Cycle

Failover to the Standby Database

Configuration of the Standby Database Environment

Number of Standby Databases

Method of Transferring Archived Redo Logs to the Standby Site

Location and Directory Structure of Primary and Standby Sites

Standby Database Maintenance

Checking the Status of Archived Redo Logs

Backing Up the Standby Database

Responding to Physical Changes in the Primary Database

Standby Database Statements

2 Preparing a Standby Database

Assessing the Environment Before Standby Database Creation

How Should the Standby Database Be Updated?

Should the Standby Database Reside on a Separate Host?

How Should You Configure the Online Redo Logs in the Primary Database?

How Should You Connect to the Standby Database After Failover?

Setting Up a Standby Database: Basic Tasks

Preparing a Standby Database for Managed Recovery: Basic Tasks

Preparing a Standby Database for Manual Recovery: Basic Tasks

Creating the Standby Database Files

Creating the Standby Datafiles

Creating the Standby Control File

Transferring Files to the Standby Site

Configuring Network Files for Primary and Standby Databases

Configuring the tnsnames.ora File on the Primary Site

Configuring the listener.ora File on the Standby Site

Configuring the Primary Database Initialization Parameter File

Specifying Archive Destinations

Specifying Mandatory and Optional Archive Destinations

Enabling Archive Destination States

Configuring Oracle to Re-Archive to a Failed Destination

Configuring the Standby Database Initialization Parameter File

Configuring Standby Initialization Parameters: General Considerations

Renaming Primary Filenames in the Standby Control File

Specifying Filenames for the Standby Database Archived Redo Logs

Configuring the Standby Initialization Parameter File: Typical Settings

Configuring Parameter and Network Files: Scenario

Starting the Standby Instance in Preparation for Recovery

Starting the Standby Instance

Manually Renaming Standby Files Not Captured by Conversion Parameters

Enabling Changes to the Initialization Parameter Settings

Troubleshooting the Standby Database Configuration

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

You Cannot Mount the Standby Database

3 Managing a Standby Database

Choosing Standby Database Modes

Which Modes Are Typical in a Standby Environment?

When Is Manual Recovery Required?

Placing the Standby Database in Manual Recovery Mode

Resolving a Gap Sequence Before Initiating Managed Recovery

What Causes Gap Sequences?

Determining Whether a Gap Sequence Exists

Transmitting the Logs in the Gap Sequence to the Standby Site

Applying the Logs in the Gap Sequence to the Standby Database

Placing the Standby Database in Managed Recovery Mode

Initiating Managed Recovery Mode

Canceling Managed Recovery

Opening a Standby Database in Read-Only Mode

Considering Whether to Run in Read-Only Mode

Receiving Archived Redo Logs While in Read-Only Mode

Opening the Database in Read-Only Mode

Creating Temporary Tablespaces

Activating a Standby Database

Using a Standby Database in an Oracle Parallel Server Configuration

4 Performing Maintenance on a Standby Database

Monitoring Events That Affect the Standby Database

Monitoring the Primary and Standby Databases

Determining Which Archived Logs Have Been Received by the Standby Site

Determining Which Logs Have Been Applied to the Standby Database

Responding to Events That Affect the Standby Database

Adding Tablespaces or Datafiles to the Primary Database

Renaming Datafiles on the Primary Database

Adding or Dropping Redo Logs on the Primary Database

Resetting or Clearing Unarchived Redo Logs on the Primary Database

Altering the Primary Database Control File

Taking Datafiles in the Standby Database Offline

Performing Direct Path Operations

Refreshing the Standby Database Control File

Clearing Online Redo Logs

Backing Up the Standby Database

5 Standby Database Scenarios

Scenario 1: Creating a Standby Database on the Same Host

Step 1: Plan the Standby Database.

Step 2: Create the Standby Database.

Step 3: Configure the Network Files.

Step 4: Configure the Primary Database Parameter File.

Step 5: Configure the Standby Database Parameter File.

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

Step 7: Identify the Logs in the Gap Sequence.

Step 8: Copy the Logs in the Gap Sequence to the Standby File System.

Step 9: Apply the Logs in the Gap Sequence to the Standby Database.

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

Scenario 2: Creating a Standby Database on a Remote Host

Step 1: Back Up the Primary Database Datafiles.

Step 2: Create the Standby Database Control File.

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

Step 4: Configure the Network Files.

Step 5: Start the Listener on the Standby Site.

Step 6: Configure the Standby Initialization Parameter File.

Step 7: Copy the Standby Initialization Parameter File.

Step 8: Start the Standby Database.

Step 9: Configure the Primary Initialization Parameter File.

Step 10: Apply the Logs in the Gap Sequence.

Step 11: Place the Standby Database in Managed Recovery Mode.

Scenario 3: Accommodating Physical Changes in the Primary Database

Adding a Datafile to the Primary Database

Renaming a Datafile in the Primary Database

Deleting a Datafile or Tablespace in the Primary Database

Adding or Removing Online Redo Logs

Altering Control Files

Refreshing the Standby Database Control File

Physical Changes That Require You to Rebuild the Standby Database

Scenario 4: Recovering After the NOLOGGING Clause Was Specified

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

Scenario 6: Configuring Client Application Failover

Local TNS Configuration

Oracle Names Server Configuration

Transparent Application Failover (TAF) Configuration

Manual Network Configuration

Scenario 7: Recovering After a Network Failure

Scenario 8: Re-Creating a Standby Database

Scenario 9: Standby Database with No Ongoing Recovery

Managing a Standby Database with No Ongoing Recovery

Activating a Standby Database with No Ongoing Recovery

Scenario 10: Standby Database with a Time Lag

Creating a Standby Database with a Time Lag

Managing a Standby Database with a Time Lag

Rolling Back the Database to a Specified Time

Bypassing the Time Lag and Activating the Standby Database

Index