ScalingRule - Amazon EMR
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A scale-in or scale-out rule that defines scaling activity, including the CloudWatch metric alarm that triggers activity, how EC2 instances are added or removed, and the periodicity of adjustments. The automatic scaling policy for an instance group can comprise one or more automatic scaling rules.



The conditions that trigger an automatic scaling activity.

Type: ScalingAction object

Required: Yes


A friendly, more verbose description of the automatic scaling rule.

Type: String

Required: No


The name used to identify an automatic scaling rule. Rule names must be unique within a scaling policy.

Type: String

Required: Yes


The CloudWatch alarm definition that determines when automatic scaling activity is triggered.

Type: ScalingTrigger object

Required: Yes

See Also

For more information about using this API in one of the language-specific Amazon SDKs, see the following: