Operating Systems: AIX, HP-UX, Linux, Solaris, Windows, z/OS
Components of dynamic operations
WebSphere Virtual Enterprise is built on features of autonomic computing in the dynamic operations environment. With these features the application server environment can expand and contract as the business demands. Using the autonomic managers in WebSphere XD environment, dynamic operations can make logical decisions based on business goals.
The features of WebSphere Virtual Enterprise also apply to the management of the WebSphere Extended Deployment Compute Grid environment and its associated background workload when the two features are deployed together. Therefore, if you are a customer of WebSphere Extended Deployment Compute Grid, have both products.
WebSphere Virtual Enterprise does not support Session Initiation Protocol (SIP) features on the z/OS operating system.
The dynamic operations environment has the following components:
- Operational policy
- An operational policy is a business, or performance objective that supports specific goals for specific requests. Operational policies include service and health policies. A service policy defines a business goal and an importance and contains one or more transaction classes. For a given work class, a rule condition maps to a transaction class which belongs to a service policy. The service policy contains the business goal requirements and the work class contains the work description upon which the service policy is applicable. The combination of these policies is read by the dynamic operations environment to make decisions on HTTP, SOAP, JMS, SIP, and IIOP work requests.
- Dynamic clusters
- A dynamic cluster is an application deployment target that is expandable and contractible, as needed by the dynamic operations environment. Dynamic cluster instances are created on nodes that meet the criteria of a membership policy that you specify when you create the dynamic cluster.
- Autonomic request flow manager
- The autonomic request flow manager (ARFM) has numerous functions:
- Uses queuing of incoming messages in edge-based gateways to provide computing power overload protection and differentiated service. The computing resource protected from overload is typically CPU power. The differentiated service aims to provide the best balanced performance results among various flows of traffic, relative to the given operational policy and current offered load.
- Can optionally exert dialog/session-oriented admission control for the sake of computing power overload protection.
- Sends information to the placement controller about each cluster to enable the placement controller to optimize the placement for the operational policy and currently offered load. The information about a given cluster is the relationship between computing power and service utility for that cluster.
- On demand router
- On demand router (ODRs) are intelligent HTTP proxies and/or a SIP SLSP (StateLess Sip Proxy) proxy. SIP proxy servers in WebSphere Virtual Enterprise, and perform part of the ARFM functions. ODRs are the point of entry into a product environment and are gateways through which HTTP requests and SIP messages flow to back-end application servers. It can momentarily queue requests for less important applications in order to allow request from more important applications to be handled more quickly or to protect back-end application servers from being overloaded. The ODR is aware of the current location of a dynamic cluster's server's instances, so that requests can be routed to the correct endpoint. The ODR can also dynamically adjust the amount of traffic sent to each individual server instance based on process utilization and response times. Note that for an inbound SIP/UDP message, the ODR might route the message to another ODR in order to properly check for and handle UDP retransmission.
- Dynamic workload manager
- The autonomic request flow manager classifies and prioritizes requests to application servers based on the demand and policies. The dynamic workload manager then distributes the requests among the nodes in a dynamic cluster to balance the work.
- Application placement controller
- The application placement controller is an autonomic manager in the dynamic operations infrastructure that supports the fluid mobility of applications within a dynamic cluster. The application placement controller adds application server instances when the work is more than can be handled by the current application, and stops application servers when there are too few requests for the number of started applications.
- Health controller
- The health controller constantly monitors the defined health policies. When a condition specified by a health policy is not met in the environment, the health controller assures that the configured actions are taken to correct the problem.
- EWLM
- The enterprise workload manager (EWLM) manages sub-goals and resource allocations for the larger environment which contains WebSphere Virtual Enterprise.
Related concepts
Overview of dynamic operations
Operational policies
Related tasks
Configure health management
Enabling the on demand router to work with IBM Enterprise Workload Manager
Configure dynamic application placement
Creating ODRs
Configure the autonomic request flow manager
Creating dynamic clusters
Deploying applications with defined service levels