Sun GlassFish Enterprise Server 2.1 High Availability Administration Guide

Auto-clustering for non-HA Clusters

Till now, the administrator had to set up 'non-Highly Available' MQ clusters (MQ clusters with a master broker) separately as explained in the procedure following this section. In this release, in addition to the manual process (of type REMOTE) of setting up an MQ cluster, Enterprise Server provides 'auto-clustering,' which means that a co-located non-HA cluster (of type LOCAL) will be created automatically when a user creates an Application Server cluster. This will be the default mode of creating MQ clusters. For example, when the administrator creates an Application Server cluster with three Application Server instances, each Application Server instance will be configured to work with a co-located broker, and as a result the three MQ broker instances will be made to form an MQ cluster transparently. The first Application Server instance's MQ broker will be set to be the master broker. Auto-clustering, however, has a disadvantage too. If the administrator adds an instance to the cluster, the MQ broker instance created automatically will not be able to take part in the cluster. This behavior also applies if an instance is removed from the cluster.