Monitoring Process

The Microsoft Application Center 2000 (Application Center) monitoring process includes four steps:

  • Data generation

  • Data logging

  • Data summarization

  • Data use

Each of these steps is described in the following sections.

Data Generation

Application Center, Microsoft Health Monitor 2.1, and Microsoft® Windows® 2000 generate events and performance counters and provide them to Windows Management Instrumentation (WMI). Application Center subscribes to, or listens for, a subset of WMI events and captures them to a log for use later by the Application Center user interface. Application Center also includes extended information about its events, called event details, and specific troubleshooting information.

Events are generated automatically in response to a specific occurrence on a cluster or cluster member. These events tell you about what is going on in your system. These events are crucial to understanding which actions to take to solve problems that are associated with events and errors.

Data Logging

The monitoring data that is gathered by Application Center is logged to and stored in a Microsoft SQL Server 2000 database, Application Center Events and Performance Logging, which is in the Application Center installation directory at %Program Files%\Microsoft SQL Server\MSSQL$MSAC. This database is exactly like SQL Server in its tables' infrastructure and function. You use the same queries, stored procedures, and other data access methods that you use for SQL Server. You can use the information in this database for a variety of operations, including query by the user interface for displaying purposes or query by scripts or stored procedures for archiving or summarizing data.

Logging the monitoring data rather than consuming it in real time allows the data to be displayed more flexibly and provides a simple and structured mechanism for other applications and services to access the data. Because this data is stored in tables, you can use Structured Query Language (SQL) queries to generate reports or archive the data before it is overwritten or summarized.

Application Center scans the 1-Minute, 15-Minute, and 2-Hour logs for data points that are older than the date specified in the Keep logged events for (days) box in the Events Properties dialog box. All data points that are older than this date are removed from the event log. Because data summarization provides several levels of granularity that correspond to the different time frames, Application Center can show data points for several different time frames. For example, the data points for the last 15 minutes are more granular than the data points for the current day.

You can choose to install Application Center without installing Application Center Events and Performance Logging. If you do this, you will no longer be able to view data in the Events view or the performance chart, nor will you be able to archive data or generate reports programmatically.

Bb687494.caution(en-us,TechNet.10).gif Caution   If you do not install Application Center Events and Performance Logging, all event and performance counter data will not be available unless you use some other method to capture and log the data. Only a subset of Application Center events logged by the Windows 2000 Event Log will be available.

Data Summarization

Application Center collects detailed information about cluster and member status. Because Application Center collects a large amount of data, the file sizes of the Application Center Events and Performance Logging tables can grow large. If all this information is stored for a long time, it quickly consumes too much disk space. Therefore, to conserve disk space and to keep these files small, Application Center periodically summarizes the stored data and relogs it to a summarization table.

Data summarization occurs for two data sets:

  • Event data, which is kept in the log for a set number of days before it is removed. You can set this time period in the Application Center snap-in. The default is 15 days. Events are removed from the database after the specified time period.

  • Performance counter data, which is collected every 10 seconds and is summarized, or rolled-up, in four intervals: 1 minute, 15 minutes, 2 hours, and daily. These times are synchronized across all members.

Performance view

Table Name

Collection Interval

Summarized every

Stored for

15 minutes


10 seconds

Every minute

1 day

2 hours


1 minute

Every 15 minutes

1 day

1 day


15 minutes

Every 2 hours (even hours)

1 day

1 week


2 hours

Every day (midnight)

10 days

3 months


1 day

Not summarized

30 days

Both of these processes involve broadening the data granularity. For example, the data from all the days of one week are summed up into a smaller table for the week. When data is summarized for display or re-storage, there are certain implications to consider:

  • As you view progressively longer time frames, you see less data details. The longer time frames are intended as a data summarization for representing trends over time.

  • To see more data detail, you must collect data more often, which results in greater consumption of disk space.

Bb687494.note(en-us,TechNet.10).gif Note   If detail is important in your monitoring and analysis, archive the detailed data before it is summarized or deleted.

Data Use

Application Center is the primary consumer of the event and monitoring information that it logs. The user interface, especially the Events view, performance chart, and cluster status, displays this information for the cluster or member. You can customize these views.

You can use SQL Server 2000 Data Transformation Services (DTS), SQL Server Agent, or some other similar application to archive data for later use in reports. You can export the information to various formats, including SQL Server 7.0 tables, Microsoft Excel spreadsheets, and Microsoft Access databases.

You can use Active Server Pages (ASP) applications, or similar scripts or applications, to perform queries on the event and monitoring data that Application Center Events and Performance Logging records, and then generate reports from the data. These applications can use SQL queries against the data tables, retrieve and filter the returned data, display the data, and create another table to store the reported data.

Bb687494.note(en-us,TechNet.10).gif Note   Application Center version 1.0 does not provide report generation, reporting features, or special queries.

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