19.2 Advisor Types

There are two types of Advisor:

• Expression-based

• GUI-based

Expression-based Advisors

The majority of Advisors use a simple expression to evaluate the data collected by the monitoring Agent. These expressions use the following syntax:

%VariableName% operator THRESHOLD

where:

• %VariableName% is the monitored value. The variables correspond to elements of the data collected by the Agent.

• operator is a mathematical operator such as <, > !, =, and so on.

• THRESHOLD is the Advisor-defined limit for the monitored value.

These expression-based Advisors evaluate the monitored values against the defined thresholds. Expression-based Advisors can evaluate percentage values, time/duration values, or check for the existence of specific configuration values.

More complex expressions are also used by concatenating a variety of different variables. It is also possible to perform calculations on the results returned by these variables within the expressions.

Expression-based advisors are described in Chapter 20, Expression-Based Advisor Reference.

GUI-based Advisors

The GUI-based Advisors contain more configuration options than the expression-based Advisors. These Advisors evaluate many more values than the expression-based Advisors and do not use the same expression-based evaluation system.

The following example shows the General section of the Agent Health Advisor:

Figure 19.5 Agent Health - General

GUI-based advisors are described in Chapter 21, GUI-Based Advisor Reference.