ExpressCluster X 3.1 for Linux Getting Started Guide - Nec

Failover mechanismDifferent Application – Multi Directional Standby Cluster SystemIn the different application multi-directional standby cluster system, different applications areactivated on multiple servers and these servers also operate as standby servers. The applications donot have to support multi-directional standby operation. A load distribution system can be built perapplication unit basis.ApplicationApplicationApplicationFailoverApplication- Operation 1 and operation 2 use different applications.Figure 2-7 Different application multi directional standby cluster systemNode to Node ConfigurationThe configuration can be expanded with more nodes by applying the configurations introducedthus far. In a node to node configuration described below, three different applications are run onthree servers and one standby server takes over the application if any problem occurs. In auni-directional standby cluster system, one of the two servers functions as a standby server.However, in a node to node configuration, only one of the four server functions as a standby serverand performance deterioration is not anticipated if an error occurs only on one server.Active Active Active StandbyAP A AP B AP CError!Active Active Active StandbyAP AAP CAP BFigure 2-8 Node to Node configurationSection I Introducing ExpressCluster39