Chapter 5. Overview

The JBoss HTTP Connector mod_cluster is a reduced-configuration, intelligent load-balancing solution for JBoss Enterprise Application Platform, based on technology originally developed by the JBoss mod_cluster community project.
The JBoss HTTP connector load-balances HTTP requests to JBoss Enterprise Application Platform and JBoss Enterprise Web Server worker nodes, using Apache HTTP Server as the proxy server.

5.1. Key features

Apache HTTP Server-based
The JBoss HTTP Connector mod-cluster uses Apache HTTP Server as the proxy server.
Real-time load-balancing calculation
The JBoss HTTP Connector mod_cluster creates a feedback network between the worker nodes and the proxy server. The mod_cluster service is deployed on each of the worker nodes. This service feeds real-time load information to the proxy server. The proxy server then makes intelligent decisions about where to allocate work, based on the current load on each worker node. This real-time adaptive load distribution results in increased optimization of resources.
The information that is reported by the worker nodes and the load-balancing policy used by the proxy are both customizable.
Routing based on real-time application life-cycle
The JBoss HTTP Connector mod_cluster service deployed on the worker nodes relays application life-cycle events to the proxy server. This allows the server to dynamically update its routing table. When an application is undeployed on a node, the proxy server no longer routes traffic for that application to that node.
Automatic Proxy Discovery
The proxy server can be configured to announce its presence via UDP multicast. New worker nodes discover the proxy server and add themselves to the load-balancing cluster automatically. This greatly reduces the configuration and maintenance needed. When UDP multicast is not available or is undesirable, worker nodes are configured with a static list of proxies.
Multiple Protocol Support
The JBoss HTTP Connector mod_cluster can use HTTP, HTTPS, or Apache JServ Protocol (AJP) for communication between the proxy and the worker nodes.