This is the new CloudFormation Template Reference Guide. Please update your bookmarks and links. For help getting started with CloudFormation, see the AWS CloudFormation User Guide.
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 CloudFormation template, use the following syntax:
JSON
{ "SlidingWindow" :Json, "WallClockWindow" :WallClockWindow}
YAML
SlidingWindow:JsonWallClockWindow:WallClockWindow
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
