Sun GlassFish Enterprise Server 2.1 Deployment Planning Guide

Variation of Separate Tier Topology

A variation of the separate tier topology is to increase the number of Enterprise Server instances by adding more machines horizontally to the configuration. For example, add another machine to the example configuration by creating a new Enterprise Server instance. Similarly, increase the number of HADB nodes by adding more machines to host HADB nodes. Recall you must add the HADB nodes in pairs with one node for each DRU.

Variation of Separate Tier Topology illustrates this configuration.

Figure 3–4 Variation of Separate Tier Topology

Variation of Separate Tier Topology

In this configuration, each machine hosting Enterprise Server instances has two instances. There are thus a total of six Enterprise Server instances in the cluster.

HADB nodes are on machines SYS3, SYS4, SYS5, and SYS6.

DRU0 comprises two machines:

DRU1 comprises two machines:

Each machine hosting HADB nodes hosts two nodes. Thus, there are a total of eight HADB nodes: four active nodes and four spare nodes.