Data points

Data sources can return data for one or more performance metrics. Each metric that a data source retrieves is represented by a data point.

You can define data points for data sources with all source types except SNMP and VMware. Because these data source types each rely on a single data point for performance metrics, additional data point definition is unnecessary.

  1. From the navigation menu, choose Advanced > Monitoring Templates.
  2. In the Data Sources area, highlight the row that contains the data source.
  3. From the action menu, choose Add Data Point.
  4. In the Add Data Point dialog box, enter a name for the data point, and then click Submit.
  5. Double-click the new data point and enter information or make selections to define it:
    • Name- Displays the name that you entered in the Add a New DataPoint dialog box.
    • RRD Type - Review the following considerations, and then specify the data source type to use for storing data for this data point.
      • COUNTER - Saves the rate of value change over a step period (interval). COUNTER assumes that the value is always increasing (the difference between the current and the previous value is greater than 0). Example use: Traffic counters on a router.
      • DERIVE - Same as COUNTER, but allows negative values. Example use: To see the rate of change in free disk space on a server.
      • GAUGE - Does not save the rate of change, but saves the actual value. There are no divisions or calculations. Example use: To see memory consumption in a server.
      • ABSOLUTE - Saves the rate of change, but assumes that the previous value is set to 0. The difference between the current and the previous value always equals the current value. Thus, ABSOLUTE stores the current value, divided by the step interval.
    • Create Command - Enter an RRD expression that is used to create the database for this data point. If you do not enter a value, then the system uses a default that is applicable to most situations.
    • RRD Minimum - Enter a value. This system ignores values less than this number.
    • RRD Maximum - Enter a value. This system ignores values greater than this number.
  6. Click Save.