Introducing Elasticity for Dynamic Clusters with Apache
This article updates an earlier blog by replacing Oracle Traffic Director (OTD) with Apache.
The WebLogic Server Elasticity Framework
The following diagram shows the different components of the elasticity framework for WebLogic Server:
Integration with Apache
The elasticity framework integrates with Apache through the WebLogic Apache Proxy Plug-In. By default, the plug-in parameter DynamicServerList is ON, so when a scaling event occurs, the plug-in recognizes the correct servers in the cluster and routes the requests accordingly. Also, the lifecycle management services for the domain need to be enabled, as described below.
To enable the Lifecycle Manager on the WebLogic Server domain:
In the meantime, you can download a demonstration of policy-based scaling with Apache integration from here. See the documentation on how to set it up and run it here.
Policy-Based Scaling demonstration files and documentation:
WebLogic Server 220.127.116.11.0 Documentation
Configuring Elasticity for Dynamic Clusters in Oracle WebLogic Server
Configuring WLDF Policies and Actions
Dynamic Clusters Documentation
Java EL 3.0 Specification