Membership

A load balancer group generally contains two or more members. Members can be defined through static or dynamic membership.

Static membership

A load balancer group that uses a static membership configuration contains the configuration settings that a DataPower® administrator explicitly defined. These settings do not change except under the following conditions.
  • The processing of a stylesheet changes configuration settings for group members.
  • An administrator enables and configures the workload management feature.

Dynamic configuration

A load balancer group that uses a dynamic membership configuration retrieves membership data through the workload management feature. To create a dynamic membership configuration, you need to enable and configure the workload management feature.

Even after workload management is enabled and configured, a firmware reload uses the persisted configuration. Only after retrieval of the workload management information and updating group membership can the group use dynamic weight and membership information in any decision.

When enabled, the load balancer group retrieves runtime information from the WebSphere® On Demand Configuration (ODCInfo) application. This information overrides the membership information in the running configuration of the load balancer group. The retrieved workload management information alters the membership and weight of members in the group so that the group can route traffic to the application server that can best handle the load.

As new servers are brought online or as existing servers are taken offline, the membership information in the load balancer group adapts to these changes.