Book Image

Oracle Data Guard 11gR2 Administration : Beginner's Guide

Book Image

Oracle Data Guard 11gR2 Administration : Beginner's Guide

Overview of this book

Data Guard is the high availability, disaster recovery and data replication solution for Oracle Databases. With the huge growth of Data Guard it's getting harder to encounter an Oracle DBA not dealing with Data Guard. Since it's a common DBA task to provide high availability of databases, Data Guard is a must-know topic for every Oracle Database Administrator."Oracle Data Guard 11g R2 Beginner's Administration Guide" is a practical guide that provides all the information you will need to configure and maintain Data Guard. This book will show you what Data Guard can really do.By following the practical examples in this book, you'll learn to set up your Data Guard Broker, the management framework for Data Guard configurations. Learn and implement different data protection modes, perform role transitions between databases (switchover and failover) and configure Active Data Guard. Next, we will dive into the features of Snapshot Standby. The book progresses into looking at Data Guard configuration with other Oracle products (such as EM, RAC, and RMAN) and patch databases in Data Guard. The final chapters will cover commonly encountered Data Guard issues and Data Guard best practices, which are very important to make a Data Guard configuration perfect and take maximum advantage of Data Guard properties.
Table of Contents (19 chapters)
Oracle Data Guard 11gR2 Administration Beginner's Guide
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Pop Quiz Answers
Index

Corruption detection, prevention, and automatic repair with Oracle Data Guard


Corruption in an Oracle database block means that a block doesn't contain the data that the database expects to find. This can be caused by various failures in the hardware environment, including disks, disk controllers, memory or network components or software errors in the operating system, firmware, the volume manager, and the Oracle database software itself.

Oracle offers some initialization parameters to control the level of corruption prevention and detection. Of course, a higher level brings performance issues with it. In a Data Guard configuration, using the standby database for corruption detection and prevention will bring higher data protection and availability with less performance effect on the primary database.

Let's first start with learning the three types of block corruption in Oracle databases.

  • Physical block corruption: In a physically corrupted database block, the block header may be corrupted...