# Clustering Guide

## Introduction

JOnAS provides a full solution for clustering that ensures high availability and scalability of J2EE applications.

- At the web level through
  - Apache/mod_jk for equilibrating the HTTP flow between multiple JOnAS/Tomcat instances
  - Tomcat for providing a TCP-based solution and replicating the HTTP session, thus ensuring their high availability
- At the JNDI level through CMI and its replicated registry
- At the EJB level (RMI requests) through CMI and its cluster stub
- At the JMS level through JORAM server and JORAM HA
- At the JDBC level through C_JDBC/Sequoia

The Howto document JOnAS clustering is a guide for configuring the clustering features of JOnAS.

Cluster management is described in Domain and Cluster Management in JOnAS chapter.