# Inheritance

Inheritance is a mechanism for applying common settings to nested configuration objects. Settings defined at the [configuration] level apply to all other sections whereas [widget] settings apply to the widget itself as well as nested [series] sections.

Inheritance hierarchy:

[configuration]
  [group]
    [widget]
      [series]

Inheritance makes syntax more compact and makes it easy to replace common settings.

# Overriding

To modify the inherited setting, the setting must be set to a new value in the lower-level object.

[configuration]
  entity = e-1

  [widget]
    # Override 'entity' for this particular widget
    entity = e-2

To reset an inherited setting to the default value, specify the name of the setting as an empty string:

statistic =

If a setting needs to be set to an empty string, use double quotes:

statistic = ""

# Example

If all widgets in a portal are created for the same entity, set the entity setting at the [configuration] level.

[widget]
  type = chart
  
  # The metric field is inherited by all series in the widget
  metric = nmon.cpu_total.busy%

  [series]
    entity = awsswgvml001
  [series]
    entity = nurswgvml006

  # Metric is overridden for this series
  [series]
    metric = mpstat.cpu_busy%
    entity = nurswgvml007

In this example, the same metric is inherited by all series in the widget because the metric is defined at the [widget] level however the second series overrides the inherited value with the metric = mpstat.cpu_busy% setting.

# Portal Example