Introduction
Ever since I have started looking at the Oracle database engine a little more than a decade ago, I have been fascinated by its features and the way it integrates with the underlying platforms it runs on. Before studying Oracle at the university as part of my degree I was exposed to MySQL (still independent then, and version 3.23) and thought that Oracle couldn’t be so different. After all, it’s about insert, delete, update, and commit, right? It is almost ironic how wrong I was! Over the years there was only one thing that became clearer and clearer: the more I learned about the product, the less I thought I understood. Although that isn’t really the case, one can’t help escaping that feeling sometimes. Add in the constant change of the software to meet Oracle’s customer needs then you get the picture. What makes it difficult to keep up to date is the fact that you can find a lot of information—sometimes conflicting—on the Internet about our favorite database engine.
I personally think that all DBAs have to keep an open mind and try to do the best we can to keep up with new releases to provide an ultimately great service to our end users who should be happy to be able to use a well-maintained database estate. I hope the book you are about to read helps you on this mission: instead of having to dissect the available information “out there” I went through it and analyzed it to the best of my abilities so you don’t have to spend the same time and effort.
Note Oracle as a company has acquired an enormous number of smaller and not-so-small companies during the last few years. When speaking of “Oracle” in this book you can safely assume the database engine is being referred to, unless otherwise stated.
In this introduction the general structure of the book is presented, my motivation for writing it and a guide on how to approach the material. Don’t be intimidated by the page count, the chapters follow what I think is a logical structure.
How This Book Is Structured
This book has been written with one goal in mind: to help technical and managerial staff alike to make best use of the most current Oracle database release in order to build a consolidated database environment. The book follows what could be a potential path to adopting a consolidation strategy for your company or a project. Although the focus clearly is with Linux and the x86-64 platforms, I have no intention of making this the platform of your choice for your consolidation project. Even though I think that you would be a very good value for the money out of this platform, it is by far not ideal to introduce an unknown platform to the already complex equation dealing with database consolidation. Many companies have a preferred hardware platform for which trained and experienced staff is available. Consolidation projects can be challenging, and do not need additional challenges by the introduction of an unfamiliar platform to the hardware estate.
If a new hardware platform is well maintained by the vendor though, who provides a balanced, well-engineered system right from the start then there is great value in such a product. Rather than going over a certification and validation cycle yourself you rely on the vendor to ensure that the components of the system are compatible, and that drivers as well as firmware combinations have been tried and tested. Oracle’s own Engineered Systems are a great example for this hardware category.
The book you are about to read tries to help you along the various stages of the consolidation project, from planning to implementation. In my opinion consolidation projects using Oracle 12c will need to provide answers to the following key questions:
- Which Operating System should be chosen?
- How should the database instance be protected from failure?
- How can I increase availability for the solution?
- How much automation can be put into the provisioning of the stack?
- How can I make use of the new Pluggable Databases Feature?
- How should I monitor the environment?
- How do I protect the database from site failure, and how can it be backed up and recovered?
It begins with background material about some of the current challenges in IT and ways users have already started coping with them. First of all it’s important to understand the importance of consolidation in the IT industry, and which technical evolutions in the x86-world made them possible. Another section in the same chapter describes the Cloud Computing hype, which every reader probably has heard about.
The next chapter introduces Oracle 12c: which features are new with the obvious focus on database consolidation but some other interesting ones as well. Other additional and noteworthy features making the DBA’s life easier will be introduced as well. Since there is a lot of uncertainty about Oracle Automatic Storage Management (ASM) in the field, a section has been dedicated to it.
The next chapters are dedicated to supporting infrastructure. Chapters 3 and 4 introduce different infrastructure options followed by various methods for protecting the consolidated database and offers other suggestions to the deployment of the database. The last thing anyone wants to see is a database containing a lot of critical information from multiple applications that crashes and creates an unnecessary and avoidable outage. Depending on how you want to play it and how much budget is available different ways for protecting the database instance are available. The chapters assume that you are building your own system rather than using one available.
Before one can install the Oracle software you have to install the underlying operating system. Although Oracle still exists for a large number of platforms I decided to present the installation of Linux. The probability that Linux will be used for your consolidation project is quite high and I am hoping to provide you with some benefit about the installation of the operating system.
Installing the Oracle software is the next logical step after the operating system has been configured properly. This again is demonstrated on the Linux platform. Following the Oracle installation you can read a chapter about Pluggable Databases, the exciting new consolidation features of Oracle 12c.
The following chapter is dedicated to monitoring Oracle 12c. A great number of monitoring tools are available for the Oracle database, but since Oracle themselves own their Enterprise Manager which has undergone substantial redevelopment for version 12 this tool has been chosen as the monitoring solution of choice.
No important production database deployment is complete without a disaster recovery solution. Chapters 9 and 10 cover Data Guard—one way of protecting the database from environment hazards and other catastrophes, small and large.
Similarly, deployments are not complete without a backup and recovery strategy. A dedicated chapter explores which tools are available for backup and recovery, and how to integrate them into the enterprise-wide solution.
The final chapter explains possible ways to upgrade to Oracle 12.1.
A word about print screens
One of the comments I read about the previous book project I was involved in is related to print screens. An advanced Oracle user complained about the print screens, essentially saying that the use of print screens artificially inflated the contents of the book. Although I sympathize with the writer of the comment there are a few points I would like to add.
First of all, not everyone will have firsthand knowledge of Oracle 12c. DBAs who are about to install the new release for the first time might enjoy seeing the various screens in print when reading the book. I certainly would have! The same goes for screen output. You will find a lot of output from running commands in the book for the same reason: if you are about to perform a certain task you might find it comforting to see a little more output than just the command with the supplied command line arguments. In addition to providing more detail for the reader who can compare his to the book’s output I hope to also demonstrate that the contents of this book are based on true research. But please bear in mind that patches can alter the output of commands.
Please be careful with Licenses
This book is not a license guide. Please bear this in mind when reading about features and check with the Oracle website or your sales representative if a feature mentioned in the book is licensable separately. Notice that Oracle can change the license model over the time this book is available. You should double-check if a particular feature you would like to use requires a separate license or database pack.
Conventions
Throughout the book, I have tried to keep a consistent style for presenting commands and their results. Where a piece of code is presented in the text, it is presented in fixed-width font, such as this example. Where it made sense to display it you should see the context in which a command has been executed in the SQL*Plus SQLPROMPT variable.
SYS@CDB$ROOT> select name, cdb from v$database;
The syntax of the command is most often provided for reference, the preceding paragraphs should already have provided background information about the command.
A similar approach has been chosen for operating system commands. Normally you should see commands shown as in this example:
[oracle@server1 ∼]> df –h /u01
The shell’s PS1 variable follows the conventions set on Oracle Linux 6.x and many other popular Linux distributions using the Bourne Again Shell (BASH) as their default command line interpreter. It shows the account name followed by the @-sign and the server name on which the command has been executed. The standard accounts you will see throughout the book are root, oracle, and grid.
You will notice that most of the shell-scripts are written for BASH as found on Oracle Linux 6.x. Shell scripts are not necessarily compatible between interpreters, and care should be used to evaluate and test scripts first before using them on actual systems.
Critical thinking welcome!
The book is written from my point of view, and opinions are my own. To loosely quote Jonathan Lewis: “just because it is written does not mean it is right.” If you disagree with passages of the book, I would like to know. Email me your questions and constructive remarks and I will be happy to reply. Since a book is a static object once in print I intend to provide errata and updates on my own and Apress’s website.
Downloading the code
The code for the examples shown in this book is available on the Apress web site, www.apress.com. A link can be found on the book’s information page under the Source Code/Downloads tab. This tab is located underneath the Related Titles section of the page.