Apple Mac OS X Server Java Application Server Administration For Version 10.3 or Later Bedienungsanleitung PDF herunterladen (Seite 42)

HTTP load balancing provides a way to distribute user load among a group of application servers. The application

servers can be standalone or configured as a cluster, in which case they are know as nodes. Load balancing is

better used with sticky sessions . This means that once the load balancer (a web server) forwards a client request

to a particular application server, it sends all further requests from the client to the same application server.

Using load balancing across standalone application servers allows you to scale your deployment with little

increase in request-processing overhead. However, when an application server fails, other application servers

cannot pick up the failed-server’s load, which may provide an undesirable user experience: Users may have to

Load balancing across clustered application servers (or nodes) provides session replication among the nodes,

so that when a node fails, another node can take over its duties with little or no user impact. However, as you

add nodes to the cluster, each request may take longer to process.

This chapter explains how to enable an application to be distributable among cluster nodes and walks you

through configuring HTTP load balancing for Sun’s Pet Store using three computers: One serving only as the

web server and load balancer, and the other two serving as application-server nodes.

Distributable Applications

Before deploying an application in a cluster of nodes using the deploy-cluster configuration, make sure

that the application is distributable.

Balancing User Load and Replicating Sessions

1 2 ... 37 38 39 40 41 42 43 44 45 46 47 48 49 50

Keine Kommentare

Apple Mac OS X Server Java Application Server Administration For Version 10.3 or Later Bedienungsanleitung Seite 42