What types of mathematical conversions can be performed on SNMP Values? (NETIQKB43557)

What types of mathematical conversions can be performed on SNMP Values?

The four generic scripts: SyncGet, SyncGetTable, SyncPoll and SyncPollTable, provide four types of mathematical conversions, any or all of which can be selected. These conversions can only be used on numeric SNMP Values:

• Delta Calculation: This conversion is used to track the rate of growth in SNMP Counter Values. At each job iteration the value of the SNMP Counter is saved. This saved value is then subtracted from the latest retrieved value to calculate the difference between the value at the last iteration and the current one. Delta Calculation is atime dependent conversion; it is important to know the time elapsed between retrievals so that the difference can be converted into the time unit of choice.
• Multiplication: The SNMP Value is multiplied by the given value.
• Division: The SNMP Value is divided by the given value.
• Percentage: The SNMP Value is converted into apercentage of the given value.

It is common to use these conversions in combination. (I.E. To calculate bandwidth utilization of a network interface, the ifInOctets and ifOutOctets can be retrieved from the interface Management Information Base (MIB). To convert these raw byte counter values into percent bandwidth utilization, select Delta Calculation and Percentage and set the Percent Maximum Value parameter to the speed of the interface in bytes per second. Alternatively, to collect Kilobytes/Second select the Divisor conversion and set it to the value 1024; do no select Percentage Conversion.)

Formerly known as NETIQKB43557

• If more than one SNMP Value is being retrieved, the Generic Toolkit treats them all as independent data points and the specified mathematical conversions are performed on each Value independently.
• For the SyncPoll/SyncPollTable Scripts, Delta Calculations are always converted to time units of seconds. For the SyncGet/SyncGetTable Scripts, the time units is equal to the job interval unless the Multiplication or Division conversions are used to convert to a different time unit.
• Trying to perform mathematical conversions on SNMP String values will result in a script error. The Generic SNMP Toolkit treats the SNMP Value Types of OCTET STRING, IPADDRESS and OBJECTID as strings.