WebSphere Application Server Network Deployment provides the Intelligent Management feature that extends the quality of services provided by your middleware infrastructure. It provides the environment with application server virtualization capabilities and a host of advanced operational facilities, such as performance virtualization. This allows WebSphere to enhance operational efficiency by providing continuously available application server environments that can service high-volume transactional workloads with linear scalability and high availability.
The main features in Intelligent Management are:
Intelligent routing: Provides the ability to prioritize the routing of requests to business critical applications, following administrator-defined rules.
Health management: Provides the ability to specify conditions to be monitored and the corresponding corrective actions to be taken when the conditions are observed.
Performance management: Provides a self-optimizing middleware infrastructure based on dynamic clusters, that can automatically scale up and down the number of application server instances to meet optimum response times and business needs.
Intelligent Management introduces autonomic capabilities into your infrastructure. These capabilities are delivered through a set of components known as autonomic managers. Autonomic managers monitor performance and health statistics through a series of sensors and turn various internal control knobs to optimize system performance and perform traffic shaping.
The Intelligent Management component includes the following autonomic managers:
Autonomic request flow manager (ARFM) to perform traffic shaping of incoming requests
Dynamic workload controller to dynamically adjust server weights to even out and minimize response times across the cluster
Application placement controller to manage an application’s location within a node group in the WebSphere cell
On demand configuration manager to maintain cell topology information, track updates applied into the cell topology, and keep the ARFM and other controllers aware of its environment
The on demand router
The on demand router (ODR) server is an intelligent Java-based HTTP proxy server and SIP proxy server built on the WebSphere run time. In your environment’s architecture, it is a component that sits in front of your application servers and is responsible for managing the flow of requests into the WebSphere environment. The ODR supports health, application edition, and performance management features.
The ODR is completely asynchronous, high performing, and scalable. It can be clustered for high availability, and it handles the queuing and dispatching of requests according to operational policies. As well as functioning similarly to the web server plug-in for WebSphere Application Server, it uses session affinity for routing work requests to application servers. This allows the ODR to queue requests for less important applications so that requests from more important applications are handled quickly. Another important aspect is that it can protect systems from becoming overloaded by limiting the rate at which traffic is forwarded to application servers.