Enterprise Java Services workload management
Enterprise Java Services workload management (EJS WLM) is when the Web container and EJB container are on different appservers. The application server hosting the EJB container is clustered.
Configuring the Web container in a separate appserver from the Enterprise JavaBean container (an EJB container handles requests for both session and entity beans) enables distribution of EJB requests between the EJB container clusters, as seen in Figure 1-9.
Figure 1-9 EJB workload management
In this configuration, EJB client requests are routed to available EJB containers based on the workload management EJB selection policy (Server-weighted round robin routing or Prefer local).
Although it is possible to split the Web container and EJB container, it is not recommended because of the negative performance impact.
The EJB clients can be servlets operating within a Web container, stand-alone Java programs using RMI/IIOP, or other EJBs.