Formula Composite (Bandwidth) Monitor

The SiteScope Formula Composite Monitor is designed to simplify the monitoring of complex network environments by checking the status readings of two SNMP monitors, two Script monitors, or two Database monitors and performing an arithmetic calculation on their results.

Each time the Formula Composite Monitor runs, it returns a status based upon the result of a calculation from the specified monitors currently reporting an error, warning, or OK status. It writes the percentages reported in the monitoring log file.

Usage Guidelines

One reason you should use this monitor is if you have devices or systems in your network that return values which you want to combine in some way to produce a composite value.

If you need alert logic that is more complex than SiteScope's standard alerts will allow, you may be able to use the Formula Composite Monitor to a create custom alert behavior. For example, you have two parallel network devices that record network traffic but the values need to be combined to produce an overall figure of network traffic. This monitor may also be used to combine the results returned by scripts run on two different machines.

Note: You must create at least two individual Script, SNMP, or Database monitor instances before you can set up the Formula Composite Monitor for those monitors.

Note: Moving any of the monitors being used by the Formula Composite Monitor will cause the composite monitor to report an error. If it is necessary to move either of the underlying monitors, recreate or edit the Formula Composite Monitor to select the monitor from its new location.

Completing the Formula Composite Monitor Form

To display the Formula Composite Monitor Form, either click the Edit link for an existing Formula Composite Monitor in a monitor table, or click the Add a new Monitor to this Group link on a group's detail page and click the Add Formula Composite Monitor link.

Complete the items on the Formula Composite Monitor form as follows. When the required items are complete, click the Add Monitor button.

Items: Choose two SNMP monitors, two Script monitors, or two Database monitors (using control-click) from the selection menu that the Formula Composite Monitor should operate on.
Note: The Formula Composite Monitor currently only operates on SNMP, Script, or Database monitor types. You must configure at least two of these types of monitors before you can use this Formula Composite monitor.
Operation: Select the arithmetic operation to be performed on the results of the two monitors selected above. For example: Add the results, Multiply the results of the two monitors, Subtract the results of the first from the second, Divide the second by the first, and so forth.
Update every: Select how often the monitor should check the status readings of the selected monitors and/or groups. The default interval is to run or update the monitor once every 10 minutes. Use the drop-down list to the right of the text box to specify another update interval in increments of seconds, minutes, hours, or days. The update interval must be 15 seconds or longer.
Title: Enter a title text for this monitor. This text is displayed in the group detail page, in report titles, and other places in the SiteScope interface. If you do not enter a title text, SiteScope will create a title based on the host, server, or URL being monitored.

Advanced Options

The Advanced Options section presents a number of ways to customize monitor behavior and display. Use this section to customize error and warning thresholds, disable the monitor, set monitor-to-monitor dependencies, customize display options, and enter other monitor specific settings required for special infrastructure environments. The options for this monitor type are described below. Complete the entries as needed and click the Add or Update button to save the settings.

Disable

Check this box to temporarily disable this monitor and any associated alerts. To enable the monitor again, clear the box.

Run Monitors

Check this box if you want the Formula Composite Monitor to control the scheduling of the selected monitors, as opposed to just checking their status readings. Any monitors that are to be run this way should not also be run separately, so edit the individual monitors, blank out the Update Every box for that monitor, and save the changes. Those monitors will then only run when scheduled by the Formula Composite Monitor. This is useful if you want to make sure that the monitors run one after another or run at approximately the same time.

Monitor Delay

If Run Monitors is checked, this is the number of seconds to wait between running each monitor.

Constant

Enter an operator and a constant to operate on the result of the calculation specified in the Operation item above. For example, if an Operation of Add is selected above, entering the characters *8 in the Constant box will multiply the result of the Add operation by 8. The syntax of for this box should be <operator> <number>. Valid operators are + (addition),- (subtraction), * (multiplication), and / (division). Numbers may be integers or decimals.

Verify Error

Check this box if you want SiteScope to automatically run this monitor again if it detects an error. When an error is detected, the monitor will immediately be scheduled to run again once.

Note: In order to change the run frequency of this monitor when an error is detected, use the Update every (on errors) option below.

Note: The status returned by the Verify Error run of the monitor will replace the status of the originally scheduled run that detected an error. This may cause the loss of important performance data if the data from the verify run is different than the initial error status.

Warning: Use of this option across many monitor instances may result in significant monitoring delays in the case that multiple monitors are rescheduled to verify errors at the same time.

Update Every (on error)

You use this option to set a new monitoring interval for monitors that have registered an error condition. For example, you may want SiteScope to monitor this item every 10 minutes normally, but as often as every 2 minutes if an error has been detected. Note that this increased scheduling will also affect the number of alerts generated by this monitor.

Schedule

By default, SiteScope monitors are enabled every day of the week. You may, however, schedule your monitors to run only on certain days or on a fixed schedule. Click the Edit schedule link to create or edit a monitor schedule. For more information about working with monitor schedules, see the section on Schedule Preferences for Monitoring.

Monitor Description

Enter additional information about this monitor. The Monitor Description can include HTML tags such as the <BR> <HR>, and <B> tags to control display format and style. The description will appear on the Monitor Detail page.

Report Description

Enter an optional description for this monitor that will make it easier to understand what the monitor does. For example, network traffic or main server response time. This description will be displayed on with each bar chart and graph in Management Reports and appended to the tool-tip displayed when you pass the mouse cursor over the status icon for this monitor on the monitor detail page.

Depends On

To make the running of this monitor dependent on the status of another monitor or monitor group, use the drop-down list to select the monitor on which this monitor is dependent. Select None to remove any dependency.

Depends Condition

If you choose to make the running of this monitor dependent on the status of another monitor, select the status condition that the other monitor or monitor group should have in order for the current monitor to run normally. The current monitor will be run normally as long as the monitor on which it depends reports the condition selected in this option.

List Order

By default, new monitors are listed last on the Monitor Detail page. You may use this drop-down list to choose a different placement for this monitor.

Error if

Set the conditions under which the Formula Composite Monitor should report an error status. Use the drop-down list to select a criteria based on the Result of the calculations selected for the monitor. Next select the logic operator(s) for the error criteria. Then enter the value to be used as the threshold or error trigger for this condition.

Warning if

Set the conditions under which the Formula Composite Monitor should report a warning status. Use the steps outlined in the Error if section above.

Good if

Set the conditions under which the Formula Composite Monitor should report a good status. Use the steps outlined in the Error if section above.