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The groupby clause has the form of a list of node.X or event.Y property specifications (e.g. node.customer or node.group), which are used to group events into buckets for counting: only events that share the same values for all the listed grouping properties will be counted together. For example, the groupby clause [ 'node.customer', 'event.priority' ] would cause this suppression rule to be applied independently for all combinations of customer and event priority. The clause given in the example block above will create a Customer Outage event for any individual customer with 5 outages in 60 seconds; without the groupby any 5 outages would cause a synthetic event to be created.
The common node properties are listed here, and the standard event properties are documented on this page.
Synthetic events and Storm Control
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