Programmatic Support

Application Center supports the use of programming to access various objects and interfaces in order to query, manage, and configure common administrative and reporting tasks.

For detailed information about this feature, see Chapter 11, "Cluster Administration Using the Command Line and Scripts."

Monitoring

Through the use of custom scripts, you can create tools for automatically monitoring the Application Center database in both the Monitors and Performance views. The samples provided on the installation CD, for example, can be used to

• Determine whether your database is connected and functioning.
• Run stored procedures against your database server.
• Validate a DSN.

Performance Counters

You can also use programming to install additional performance counters—either by modifying the samples that ship with the product or by creating your own definition in a MOF and compiling the source. Some examples of typical counters are provided in Table 2.10. This list is by no means exhaustive, and you can get information about the entire set of sample definitions in the Appendix or the online documentation (See: Application Center>Programmatic Information>Monitoring>Samples).

Table 2.10 Examples of Performance Counters

Category	Counter examples
Web Service	Request Execution Time, Request Wait Time, File Cache Hits %, Thread Count
System	Page reads/sec, Interrupts/sec, % DPC time, Processor Queue Length
SQL Server	Buffer Cache Hit Ratio, Number of Deadlocks/sec, Total Server Memory, % Disk Time
COM	Total Committed Transactions, Object Creations/sec, Timeout Shutdowns
Miscellaneous	NIC: Bytes Received/sec, Bytes Sent/sec, Process: Thread Count

Command-Line Administration

Application Center provides the commands summarized in Table 2.11 for command-line administration and automation through scripting. Each command has several parameters that can be used to control the behavior of the command-line tool.

Table 2.11 Command-Line Administration

Command	Description
HELP	Provides a description of the available Application Center commands, their syntax, and their usage.
LOADBALANCE	Allows the user to take a member offline, put a member online, or enable/disable load balancing. This command can also be used to set NLB weights for cluster members and obtain NLB status information.
DEPLOY	Enables the user to deploy applications (defined by Application Center) from the cluster controller.
CLUSTER	Provides the ability to change the cluster controller.
CLB	Allows the user to update the CLB routing list on the controller of an NLB (DCOM routing) cluster.

COM+ Provider

The COM+ provider enables the monitoring of COM+ data by using WMI to provide statistics about the status of COM+ applications that are running. If you are familiar with WMI and the COM+ programming framework and have access to their software development kits (SDKs), you can create your programs for interacting with the provider. This will let you build your own application monitoring and remote administration tools for a COM+ environment.