Editing the inventory_subelement.txt file

When you create a Discovery formula, you need to edit the Inventory_sublement.txt file to include the formula so it can be used by the Inventory tool. The Inventory_sublement.txt file lists the rules that Discovery uses and you need to create rules for any Discovery formulas you create.

1. Click the Metric > Formula Editor.
   The Formula Editor window appears.
2. Select the following formula type from the Options menu:
   • SNMP (Simple Network Management Protocol) - a network management protocol that is used to monitor routers and attached networks. SNMP is an application layer protocol. Information about devices managed is defined and stored in the application's Management Information Base (MIB). Operates on several OIDs.
3. Click a function button in the calculator. Your choices are as follows:

   Function	Description
   ABS	Takes the absolute value of an expression or an object.
   MOD	Takes the modulus of an expression (remainder from the full division) or of an object. This function is typically used with the INT function.
   LN	Takes the Naperian logarithm of an expression or an object.
   LOG	Takes the decimal logarithm of an expression or an object.
   e*	Takes the exponential of an expression or an object.
   10*	Takes 10 to the power of an expression or an object.
   INT	Converts the value of an expression or an object into an integer value.
   LAST	Displays the previous measurement value.
   Δ (delta)	Displays the difference between the last measurement and the previous one (x - last(x)). Results are always positive. This function is used for data whose value increases after reaching a maximum peak. This function is typically used for "counter" type MIB data.
   DIFF	Displays the difference between the last measurement and the previous one (x - last (x)). Results can be negative. This function is typically run on gauge type objects.
   Ô	Deletes the last operation.
   C	Clears the Data of Formula box.
   (	Open parenthesis.
   )	Closed parenthesis.

4. Alternatively, you can drag a function from the Functions listbox into the Data of Formula box to create a formula. Many of these functions are also available as buttons in the calculator.
   
   Or
5. Select a data type from the Type listbox. Your choices are:
   • float - a numerical value (floating point).
   • string - a character string.

     Enter a comment in the Comment box. The maximum character length is 4000.

6. Select File > Save to save your formula in the database.