Instance variables

Instance variables represent the input values for a formula.

They are declared as a capital I, followed by a number (single digit) between 1 and 9. For example:

I1, I2, I3, and so on.

You can use the following two methods to set values for the instance variables:

  • Setting values in the Instance field of the Formula Editor
  • Assigning a subelement to a request using the Request Editor
The instance field is an ASCII string, which must be constructed as the following sequence:
[name]<values>

The name is only used as a comment, for clarification of the formula syntax, expectations of the values. Values are exact strings that will be used for replacement of

To use the value of the instance variable in a formula, add %:

%I1, %I2, %I3, and so on.

Only values whose responses do not return errors are retained for interpreting the remaining lines of the formula.

The valid types for an instance variable correspond to SNMP types. They are:
  • Integer
  • IP address
  • Gauge
  • Counter
  • MacAddress
  • OctetString
  • DisplayString
  • Timeticks

These names are not case-sensitive when used in a formula.

Default instances can include a list of values or * to indicate that all instances must be used. Spaces are not allowed within a list of values for an instance variable. These are valid:
  • integer, for example: 3
  • list of integers, for example: 1,3,6,9,8,109
  • interval, for example: 4-59
  • list of integers and intervals, for example: 1,3,6,9,8-96,109,200-250
  • character string, enclosed in double quotation marks, for example: "this is a STRING"
  • pointer to a string, for example: 128.3.56.7
  • wildcard: *