7.7. Clustered Enterprise JavaBeans

7.7.1. About Clustered Enterprise JavaBeans (EJBs)

EJB components can be clustered for high-availability scenarios. They use different protocols than HTTP components, so they are clustered in different ways. EJB 2 and 3 stateful and stateless beans can be clustered.
For information on singletons, refer here: Section 8.4, “Implement an HA Singleton”.


EJB 2 entity beans cannot be clustered. This limitation is not expected to be changed.