Preface

High availability is a broad topic to discuss, and it concerns both project deployment and development. In this book, I'd like to explore the topics on clustering, load balancing, failover, and session replication.

High availability is also a very interesting topic, and the technologies provided by open source communities are especially fun. In this book we'll learn how to use JBoss EAP6 together with other JBoss and Apache community tools to build a high-availability system.

Here is a brief list of the projects we'll use in this book: JBoss EAP 6, Apache httpd, mod_jk, and mod_cluster. When I'm writing this book, JBoss EAP 6.1.0.Final is the newest product version based on JBoss AS 7.2.x and can be downloaded freely from the JBoss community. This version is very stable with its clustering features, so we'll use it in our book.

Since AS 8.x, the project name of JBoss AS has been renamed to WildFly. Though the project name changed, its design hasn't changed much, and you can reuse most of the knowledge in this book for future versions of WildFly.

JBoss EAP6 has provided a domain management feature that can help us to centralize the management of many servers. This feature is very helpful in a clustering environment, because we don't have to manage each server separately. We'll check this feature in the book.

Transportation security is usually considered critical in business applications. In this book, I'll introduce the methods of applying SSL into a clustering environment.