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AWS::CloudWatch::Alarm EvaluationWindow - Amazon CloudFormation
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AWS::CloudWatch::Alarm EvaluationWindow

The evaluation window that an alarm uses to select the range of metric data that it evaluates each time it runs. This is a union type. Set exactly one of its members, SlidingWindow or WallClockWindow. If you don't set EvaluationWindow, the alarm uses a SlidingWindow by default.

For more information, see Alarm evaluation windows in the CloudWatch User Guide.

Syntax

To declare this entity in your Amazon CloudFormation template, use the following syntax:

Properties

SlidingWindow

A sliding window, which advances each time the alarm is evaluated, forming a rolling time window. This is the default evaluation window.

Required: No

Type: Json

Update requires: No interruption

WallClockWindow

A wall clock window, which aligns the evaluated range to fixed clock boundaries that match the alarm's period, such as the top of the hour, midnight, or the start of the calendar week.

Required: No

Type: WallClockWindow

Update requires: No interruption