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JBoss 4.0 The Official Guide
JBoss® 4.0 The Official Guide
Table of Contents
Copyright
About the Authors
We Want to Hear from You!
Introduction
What This Book Covers
About JBoss
About Open Source
About Professional Open Source
What's New in JBoss 4.0
Chapter 1.  Installing and Building the JBoss Server
Getting the Binary Files
Installing the Binary Package
Basic Installation Testing
Booting from a Network Server
Building the Server from Source Code
Chapter 2.  The JBoss JMX Microkernel
JMX
The JBoss JMX Implementation Architecture
Connecting to the JMX Server
Using JMX as a Microkernel
The JBoss Deployer Architecture
Exposing MBean Events via SNMP
Remote Access to Services, Detached Invokers
Chapter 3.  Naming on JBoss
An Overview of JNDI
The JBossNS Architecture
Chapter 4.  Transactions on JBoss
Transaction and JTA Overview
JBoss Transaction Internals
Chapter 5.  EJBs on JBoss
The EJB Client-Side View
The EJB Server-Side View
The EJB Container
Entity Bean Locking and Deadlock Detection
Chapter 6.  Messaging on JBoss
JMS Examples
JBossMQ Overview
JBossMQ Configuration and MBeans
Specifying the MDB JMS Provider
Chapter 7.  Connectors on JBoss
JCA Overview
An Overview of the JBossCX Architecture
Configuring JDBC Datasources
Configuring Generic JCA Adaptors
Chapter 8.  Security on JBoss
J2EE Declarative Security Overview
An Introduction to JAAS
The JBoss Security Model
The JBossSX Architecture
The Secure Remote Password (SRP) Protocol
Running JBoss with a Java 2 Security Manager
Using SSL with JBoss and JSSE
Configuring JBoss for Use Behind a Firewall
Securing the JBoss Server
Chapter 9.  Web Applications
The Tomcat Service
The Tomcat server.xml File
The Engine Element
The Host Element
Using SSL with the JBoss/Tomcat Bundle
Setting the Context Root of a Web Application
Setting Up Virtual Hosts
Serving Static Content
Using Apache with Tomcat
Using Clustering
Integrating Third-Party Servlet Containers
Chapter 10.  MBean Services Miscellany
System Properties Management
Property Editor Management
Services Binding Management
Scheduling Tasks
The Log4j Service MBean
RMI Dynamic Class Loading
Chapter 11.  The CMP Engine
Example Code
The jbosscmp-jdbc Structure
Entity Beans
CMP Fields
Container-Managed Relationships
Declaring Queries
Optimized Loading
The Loading Process
Transactions
Optimistic Locking
Entity Commands and Primary Key Generation
JBoss Global Defaults
Datasource Customization
Chapter 12.  Web Services
JAX-RPC Service Endpoints
Enterprise JavaBean Endpoints
Web Services ClientsA JAX-RPC Client
Service References
Chapter 13.  Hibernate
The Hibernate MBean
Hibernate Archives
Using Hibernate Objects
Using a HAR File Inside an EAR File
The HAR Deployer
Chapter 14.  Aspect-Oriented Programming (AOP) Support
JBoss AOP: EJB-Style Services for Plain Java Objects
Why AOP?
Basic Concepts of AOP
Building JBoss AOP Applications
The JBoss AOP Deployer
Packaging and Deploying AOP Applications to JBoss
Appendix A.  The GNU Lesser General Public License (LGPL)
GNU General Public License
Appendix B.  Example Installation
Index
SYMBOL
A
B
C
D
E
F
G
H
I
J
K
L
M
N
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P
Q
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W
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Using Clustering

JBoss supports clustering in the embedded Tomcat service. The steps to set up clustering of Tomcat embedded containers are as follows:

1.
If you are using a load balancer, make sure that your setup uses sticky sessions. This means that if a user starts a session on node A, all subsequent requests are forwarded to node A, as long node A is up and running. For details on configuration of Apache sticky sessions, see www.ubeans.com/tomcat.

2.
If you aren't using the all configuration, make sure that cluster-service.xml is in your deploy directory. If it isn't there, copy cluster-service.xml from server/all/deploy into your deploy directory. You also need the jgroups.jar in your lib directory. You can find it in the server/all/lib directory.

3.
Start JBoss to check whether your setup works. Look at the JMX management console (http://localhost:8080/jmx-console/). Find the jboss.cache:service=TomcatClusteringCache MBean. StateString must be Started. If it is Stopped, look in the server's log file.

4.
To enable clustering of web applications, you must mark them as distributable in the web.xml descriptor. Here's an example:

<?xml version="1.0"?>
<!DOCTYPE web-app PUBLIC
    "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd ">
<web-app>
    <distributable/>
    <!-- ... -->
</web-app>

5.
Deploy your WAR as usual, and it should now be clustered.

If you have deployed and accessed your application, go back to the jboss.cache:service=TomcatClusteringCache MBean and invoke the printDetails operation. You should see output resembling the following:

/JSESSION

/n6HywRwITbY-xvzaZ0LS5Q**
n6HywRwITbY-xvzaZ0LS5Q**: org.jboss.invocation.MarshalledValue@9c1dddab

/R1T4Dapn7c8T-+Ynd9v9MA**
R1T4Dapn7c8T-+Ynd9v9MA**: org.jboss.invocation.MarshalledValue@8c0f60b6

This output shows two separate web sessions that are being shared via JBossCache. If you don't see any output, either the application was not correctly marked as distributable or you haven't accessed the part of application that places values in the HTTP session.