There are two types of Advisor:
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
%VariableName%is the monitored value. The variables correspond to elements of the data collected by the Agent.
operatoris a mathematical operator such as <, > !, =, and so on.
THRESHOLDis 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 19, Expression-Based Advisor Reference.
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:
GUI-based advisors are described in Chapter 20, GUI-Based Advisor Reference.