Book Image

Oracle Database 11g : Underground Advice for Database Administrators

By : April Sims
Book Image

Oracle Database 11g : Underground Advice for Database Administrators

By: April Sims

Overview of this book

Today DBAs are expected to deploy and manage large databases with quality service and little to no downtime. The DBA's main focus is on increasing productivity and eliminating idle redundancy throughout the enterprise. However, there is no magic set of best practices or hard and fast rules that DBAs need to follow, and this can make life difficult. But if DBAs follow some basic approaches and best practices, tasks can be performed more efficiently and effectively.This survival guide offers previously unwritten underground advice for DBAs. The author provides extensive information to illuminate where you fit in, and runs through many of the tasks that you need to be watchful of, extensively covering solutions to the most common problems encountered by newcomers to the world of Oracle databases.The book will quickly introduce you to your job responsibilities, as well as the skills, and abilities needed to be successful as a DBA. It will show you how to overcome common problems and proactively prevent disasters by implementing distributed grid computing—scalable and robust—with the ability to redeploy or rearchitect when business needs change. Reduce downtime across your enterprise by standardizing hardware, software, tools, utilities, commands, and architectural components.This book will also help you in situations where you need to install Oracle Database 11g or migrate to new hardware making it compliant with a Maximum Availability Architecture. By the end of this book you will have learned a lot and gained confidence in your abilities. You will be armed with knowledge as to which tools are best used to accomplish tasks while proactively moving towards an automated environment.
Table of Contents (14 chapters)
Oracle Database 11g—Underground Advice for Database Administrators
Credits
About the author
About the reviewers
Preface
Index

Oracle net services


As a DBA, controlling the environment is key to preventing disruptive events during migrations. Using the database parameter, LOCAL_LISTENER for each ORACLE_SID on a separate port allows the DBA to turn off or on access to that database without affecting other ports and/or ORACLE_SID(s). If you use port 1521, dynamic registration will happen for each instance on that node, and hence that port is avoided to maintain control.

Oracle recommends having multiple listeners running in multiple Oracle Homes (see Note: 429074.1), but experience has taught me that the highest version listener executable will work for any single-version, down-level database installed on a single node while preventing conflicts. You can use any combination of multiple ports and multiple listeners, but the executable comes out of only a single ORACLE_HOME location, as shown in the following listing of Unix processes:

The key to using a higher level listener is the variable TNS_ADMIN, which overrides...