Active Script Performance Monitor

This custom performance monitor lets you write VBScript and JScript to easily poll one or more more SNMP or WMI values, perform math or other operations on those values, and graph a single output value. You should only use the Active Script Performance Monitor when you need to perform calculations on the polled values. Keep in mind that although you can poll multiple values using the feature, only one value will be stored to the database: the outcome of your scripted calculation.

Reference Variables

Reference variables simplify your scripting code and enable you to write scripts efficiently, without having to grab a list of device properties, as with the Script Action and Script Active Monitor. They take care of the underlying SNMP or WMI mechanisms that you would normally have to deal with to access SNMP or WMI counters on a remote device.

By using the Context.GetReferenceVariable (variable name), you only need to specify the name of a pre-defined variable. WhatsUp Gold will use a device's credentials and connect to the target device using SNMP or WMI to retrieve the requested information. This information is stored in a variable that you can use later in your script.

Important: The use of reference variables in the Active Script Performance Monitor is optional. If you do use them, you must use Context.GetReferenceVariable,for reference variables to be polled and their data graphed.

The Dialog

• Name. The name of the monitor as it appears in the Performance Monitor Library.
• Description. The description of the monitor as it appears in the Performance Monitor Library.
• Timeout. The amount of time (in minutes) WhatsUp Gold should wait for a response to the poll.

  Note: Though the maximum timeout allowed is 60 seconds, you are highly discouraged from using a timeout longer than the default of 10 seconds. You are encouraged to use the shortest timeout possible.

• Collection interval. (For the device-specific Active Script Performance Monitor only.) The amount of time in seconds for the monitor's polling interval.
• Script type. VBScript or JScript.
• Reference variable. Add, Edit, or Remove SNMP and WMI reference variables using the respective buttons on the right of the dialog.
• Script text. Write or paste your monitor code here.

Keep In Mind

• You need to include error handling in your monitor script. Your script either needs a value to graph by using Context.SetValue, or you must use Context.SetResult to tell WhatsUp Gold that the script failed.
• Context.GetReferenceVariable will return 'null' if the poll fails for any reason.
• If you do not have a call to SetValue or SetResult, you will not see any errors, you also will not get any data graphed.
• If SetValue is used, it is not necessary to use SetResult, as SetValue implicitly sets SetResult to 0, or "good."
• Results from this performance monitor will display on Custom Performance Monitors Full and Workspace reports.
• Errors from this performance monitor will display in the Performance Monitor Error log as well as EventViewer.exe.

This script monitor has a context object that you can use to poll for specific information about the device in context.

We have provided several code samples to help you in creating useful Active Script Performance Monitors for your devices.

Troubleshooting

Having problems with your WMI monitor returning false negatives?