NonStop Systems Introduction for H-Series RVUs

The Application Server Environment
NonStop Systems Introduction for H-Series RVUs—540083-001
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Server Handling
two or more server classes for requests of different lengths. By separating the shorter
requests from the longer requests, response time stays fast and consistent at all times.
Online Reconfiguration
It is sometimes necessary to reconfigure an application. If the system administrator has
to shut down the whole system in order to add or redistribute servers or add clients, the
application and the system both fail to meet the fundamental real-time solution
requirement of continuous availability. From the business user’s point of view, the worst
time to bring down the application is when users need it most. Figure 3-8 shows how
the application server permits online reconfiguration.
As shown in Figure 3-8 the application server permits online reconfiguration of
applications. The application continues to run while the administrator reconfigures the
application, using tools and programs provided by the application server. For example,
in the WebLogic Server environment, the administrator uses the Web-based
Administration Console to reconfigure the servers of an application. The Administration
Console provides a graphical user interface that simplifies the server management
tasks.
Using the capabilities of the application server, the administrator can reconfigure
clients and servers without stopping online service to users. (Depending on the
Figure 3-8. Online Reconfiguration
Application server environment
VST023.vsd
Servers
Servers
Clients
s
Dynamic reconfiguration of online environment:
! Add or redistribute servers
! Manage communications links between clients and servers
Process and link
management
services
Administrative interface