Add a policy statement to the role's policy.

addToRolePolicy

Scale out or in, in response to a metric.

scaleOnMetric

scaleOnSchedule

Scale out or in in order to keep a metric around a target value.

scaleToTrackMetric

ScalableTarget

The maximum value that Application Auto Scaling can use to scale a target during a scaling activity.

maxCapacity

The minimum value that Application Auto Scaling can use to scale a target during a scaling activity.

minCapacity

The resource identifier to associate with this scalable target.

This string consists of the resource type and unique identifier.

Example value: `service/ecsStack-MyECSCluster-AB12CDE3F4GH/ecsStack-MyECSService-AB12CDE3F4GH`

resourceId

The scalable dimension that's associated with the scalable target.

Specify the service namespace, resource type, and scaling property.

Example value: `ecs:service:DesiredCount`

scalableDimension

The namespace of the AWS service that provides the resource or custom-resource for a resource provided by your own application or service.

For valid AWS service namespace values, see the RegisterScalableTarget
action in the Application Auto Scaling API Reference.

serviceNamespace

Role that allows Application Auto Scaling to modify your scalable target.

role

Define a step scaling action.

This kind of scaling policy adjusts the target capacity in configurable
steps. The size of the step is configurable based on the metric's distance
to its alarm threshold.

This Action must be used as the target of a CloudWatch alarm to take effect.

Add an adjustment interval to the ScalingAction.

addAdjustment

StepScalingAction

scalingTarget

How the adjustment numbers are interpreted.

adjustmentType

Grace period after scaling activity.

For scale out policies, multiple scale outs during the cooldown period are
squashed so that only the biggest scale out happens.

For scale in policies, subsequent scale ins during the cooldown period are
ignored.

cooldown

The aggregation type for the CloudWatch metrics.

metricAggregationType

Minimum absolute number to adjust capacity with as result of percentage scaling.

Only when using AdjustmentType = PercentChangeInCapacity, this number controls
the minimum absolute effect size.

minAdjustmentMagnitude

policyName

Define a scaling strategy which scales depending on absolute values of some metric.

You can specify the scaling behavior for various values of the metric.

Implemented using one or more CloudWatch alarms and Step Scaling Policies.

StepScalingPolicy

metric

The intervals for scaling.

Maps a range of metric values to a particular scaling behavior.

Must be between 2 and 40 steps.

scalingSteps

How the adjustment numbers inside 'intervals' are interpreted.

Grace period after scaling activity.

Subsequent scale outs during the cooldown period are squashed so that only
the biggest scale out happens.

Subsequent scale ins during the cooldown period are ignored.

The number of data points out of the evaluation periods that must be breaching to trigger a scaling action.

Creates an "M out of N" alarm, where this property is the M and the value set for
`evaluationPeriods` is the N value.

Only has meaning if `evaluationPeriods != 1`.

datapointsToAlarm

How many evaluation periods of the metric to wait before triggering a scaling action.

Raising this value can be used to smooth out the metric, at the expense
of slower response times.

If `datapointsToAlarm` is not set, then all data points in the evaluation period
must meet the criteria to trigger a scaling action.

evaluationPeriods

Aggregation to apply to all data points over the evaluation periods.

Only has meaning if `evaluationPeriods != 1`.

TargetTrackingScalingPolicy

targetValue

A custom metric for application autoscaling.

The metric must track utilization. Scaling out will happen if the metric is higher than
the target value, scaling in will happen in the metric is lower than the target value.

Exactly one of customMetric or predefinedMetric must be specified.

customMetric

A predefined metric for application autoscaling.

The metric must track utilization. Scaling out will happen if the metric is higher than
the target value, scaling in will happen in the metric is lower than the target value.

Exactly one of customMetric or predefinedMetric must be specified.

predefinedMetric

Identify the resource associated with the metric type.

Only used for predefined metric ALBRequestCountPerTarget.

Example value: `app/<load-balancer-name>/<load-balancer-id>/targetgroup/<target-group-name>/<target-group-id>`

resourceLabel

Indicates whether scale in by the target tracking policy is disabled.

If the value is true, scale in is disabled and the target tracking policy
won't remove capacity from the scalable resource. Otherwise, scale in is
enabled and the target tracking policy can remove capacity from the
scalable resource.

disableScaleIn

Period after a scale in activity completes before another scale in activity can start.

scaleInCooldown

Period after a scale out activity completes before another scale out activity can start.

scaleOutCooldown

The `AWS::ApplicationAutoScaling::ScalableTarget` resource specifies a resource that Application Auto Scaling can scale, such as an AWS::DynamoDB::Table or AWS::ECS::Service resource.

For more information, see [Getting started](https://docs.aws.amazon.com/autoscaling/application/userguide/getting-started.html) in the *Application Auto Scaling User Guide* .

> If the resource that you want Application Auto Scaling to scale is not yet created in your account, add a dependency on the resource when registering it as a scalable target using the [DependsOn](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-attribute-dependson.html) attribute.

CfnScalableTarget

The maximum value that you plan to scale out to.

When a scaling policy is in effect, Application Auto Scaling can scale out (expand) as needed to the maximum capacity limit in response to changing demand.

The minimum value that you plan to scale in to.

When a scaling policy is in effect, Application Auto Scaling can scale in (contract) as needed to the minimum capacity limit in response to changing demand.

The identifier of the resource associated with the scalable target.

This string consists of the resource type and unique identifier.

- ECS service - The resource type is `service` and the unique identifier is the cluster name and service name. Example: `service/my-cluster/my-service` .
- Spot Fleet - The resource type is `spot-fleet-request` and the unique identifier is the Spot Fleet request ID. Example: `spot-fleet-request/sfr-73fbd2ce-aa30-494c-8788-1cee4EXAMPLE` .
- EMR cluster - The resource type is `instancegroup` and the unique identifier is the cluster ID and instance group ID. Example: `instancegroup/j-2EEZNYKUA1NTV/ig-1791Y4E1L8YI0` .
- AppStream 2.0 fleet - The resource type is `fleet` and the unique identifier is the fleet name. Example: `fleet/sample-fleet` .
- DynamoDB table - The resource type is `table` and the unique identifier is the table name. Example: `table/my-table` .
- DynamoDB global secondary index - The resource type is `index` and the unique identifier is the index name. Example: `table/my-table/index/my-table-index` .
- Aurora DB cluster - The resource type is `cluster` and the unique identifier is the cluster name. Example: `cluster:my-db-cluster` .
- SageMaker endpoint variant - The resource type is `variant` and the unique identifier is the resource ID. Example: `endpoint/my-end-point/variant/KMeansClustering` .
- Custom resources are not supported with a resource type. This parameter must specify the `OutputValue` from the CloudFormation template stack used to access the resources. The unique identifier is defined by the service provider. More information is available in our [GitHub repository](https://docs.aws.amazon.com/https://github.com/aws/aws-auto-scaling-custom-resource) .
- Amazon Comprehend document classification endpoint - The resource type and unique identifier are specified using the endpoint ARN. Example: `arn:aws:comprehend:us-west-2:123456789012:document-classifier-endpoint/EXAMPLE` .
- Amazon Comprehend entity recognizer endpoint - The resource type and unique identifier are specified using the endpoint ARN. Example: `arn:aws:comprehend:us-west-2:123456789012:entity-recognizer-endpoint/EXAMPLE` .
- Lambda provisioned concurrency - The resource type is `function` and the unique identifier is the function name with a function version or alias name suffix that is not `$LATEST` . Example: `function:my-function:prod` or `function:my-function:1` .
- Amazon Keyspaces table - The resource type is `table` and the unique identifier is the table name. Example: `keyspace/mykeyspace/table/mytable` .
- Amazon MSK cluster - The resource type and unique identifier are specified using the cluster ARN. Example: `arn:aws:kafka:us-east-1:123456789012:cluster/demo-cluster-1/6357e0b2-0e6a-4b86-a0b4-70df934c2e31-5` .
- Amazon ElastiCache replication group - The resource type is `replication-group` and the unique identifier is the replication group name. Example: `replication-group/mycluster` .
- Amazon ElastiCache cache cluster - The resource type is `cache-cluster` and the unique identifier is the cache cluster name. Example: `cache-cluster/mycluster` .
- Neptune cluster - The resource type is `cluster` and the unique identifier is the cluster name. Example: `cluster:mycluster` .
- SageMaker serverless endpoint - The resource type is `variant` and the unique identifier is the resource ID. Example: `endpoint/my-end-point/variant/KMeansClustering` .
- SageMaker inference component - The resource type is `inference-component` and the unique identifier is the resource ID. Example: `inference-component/my-inference-component` .
- Pool of WorkSpaces - The resource type is `workspacespool` and the unique identifier is the pool ID. Example: `workspacespool/wspool-123456` .

The scalable dimension associated with the scalable target.

This string consists of the service namespace, resource type, and scaling property.

- `ecs:service:DesiredCount` - The task count of an ECS service.
- `elasticmapreduce:instancegroup:InstanceCount` - The instance count of an EMR Instance Group.
- `ec2:spot-fleet-request:TargetCapacity` - The target capacity of a Spot Fleet.
- `appstream:fleet:DesiredCapacity` - The capacity of an AppStream 2.0 fleet.
- `dynamodb:table:ReadCapacityUnits` - The provisioned read capacity for a DynamoDB table.
- `dynamodb:table:WriteCapacityUnits` - The provisioned write capacity for a DynamoDB table.
- `dynamodb:index:ReadCapacityUnits` - The provisioned read capacity for a DynamoDB global secondary index.
- `dynamodb:index:WriteCapacityUnits` - The provisioned write capacity for a DynamoDB global secondary index.
- `rds:cluster:ReadReplicaCount` - The count of Aurora Replicas in an Aurora DB cluster. Available for Aurora MySQL-compatible edition and Aurora PostgreSQL-compatible edition.
- `sagemaker:variant:DesiredInstanceCount` - The number of EC2 instances for a SageMaker model endpoint variant.
- `custom-resource:ResourceType:Property` - The scalable dimension for a custom resource provided by your own application or service.
- `comprehend:document-classifier-endpoint:DesiredInferenceUnits` - The number of inference units for an Amazon Comprehend document classification endpoint.
- `comprehend:entity-recognizer-endpoint:DesiredInferenceUnits` - The number of inference units for an Amazon Comprehend entity recognizer endpoint.
- `lambda:function:ProvisionedConcurrency` - The provisioned concurrency for a Lambda function.
- `cassandra:table:ReadCapacityUnits` - The provisioned read capacity for an Amazon Keyspaces table.
- `cassandra:table:WriteCapacityUnits` - The provisioned write capacity for an Amazon Keyspaces table.
- `kafka:broker-storage:VolumeSize` - The provisioned volume size (in GiB) for brokers in an Amazon MSK cluster.
- `elasticache:cache-cluster:Nodes` - The number of nodes for an Amazon ElastiCache cache cluster.
- `elasticache:replication-group:NodeGroups` - The number of node groups for an Amazon ElastiCache replication group.
- `elasticache:replication-group:Replicas` - The number of replicas per node group for an Amazon ElastiCache replication group.
- `neptune:cluster:ReadReplicaCount` - The count of read replicas in an Amazon Neptune DB cluster.
- `sagemaker:variant:DesiredProvisionedConcurrency` - The provisioned concurrency for a SageMaker serverless endpoint.
- `sagemaker:inference-component:DesiredCopyCount` - The number of copies across an endpoint for a SageMaker inference component.
- `workspaces:workspacespool:DesiredUserSessions` - The number of user sessions for the WorkSpaces in the pool.

The namespace of the AWS service that provides the resource, or a `custom-resource` .

Specify the Amazon Resource Name (ARN) of an Identity and Access Management (IAM) role that allows Application Auto Scaling to modify the scalable target on your behalf.

This can be either an IAM service role that Application Auto Scaling can assume to make calls to other AWS resources on your behalf, or a service-linked role for the specified service. For more information, see [How Application Auto Scaling works with IAM](https://docs.aws.amazon.com/autoscaling/application/userguide/security_iam_service-with-iam.html) in the *Application Auto Scaling User Guide* .

To automatically create a service-linked role (recommended), specify the full ARN of the service-linked role in your stack template. To find the exact ARN of the service-linked role for your AWS or custom resource, see the [Service-linked roles](https://docs.aws.amazon.com/autoscaling/application/userguide/application-auto-scaling-service-linked-roles.html) topic in the *Application Auto Scaling User Guide* . Look for the ARN in the table at the bottom of the page.

roleArn

The scheduled actions for the scalable target.

Duplicates aren't allowed.

scheduledActions

An embedded object that contains attributes and attribute values that are used to suspend and resume automatic scaling.

Setting the value of an attribute to `true` suspends the specified scaling activities. Setting it to `false` (default) resumes the specified scaling activities.

*Suspension Outcomes*

- For `DynamicScalingInSuspended` , while a suspension is in effect, all scale-in activities that are triggered by a scaling policy are suspended.
- For `DynamicScalingOutSuspended` , while a suspension is in effect, all scale-out activities that are triggered by a scaling policy are suspended.
- For `ScheduledScalingSuspended` , while a suspension is in effect, all scaling activities that involve scheduled actions are suspended.

suspendedState

The `AWS::ApplicationAutoScaling::ScalingPolicy` resource defines a scaling policy that Application Auto Scaling uses to adjust the capacity of a scalable target.

For more information, see [Target tracking scaling policies](https://docs.aws.amazon.com/autoscaling/application/userguide/application-auto-scaling-target-tracking.html) and [Step scaling policies](https://docs.aws.amazon.com/autoscaling/application/userguide/application-auto-scaling-step-scaling-policies.html) in the *Application Auto Scaling User Guide* .

CfnScalingPolicy

The name of the scaling policy.

Updates to the name of a target tracking scaling policy are not supported, unless you also update the metric used for scaling. To change only a target tracking scaling policy's name, first delete the policy by removing the existing `AWS::ApplicationAutoScaling::ScalingPolicy` resource from the template and updating the stack. Then, recreate the resource with the same settings and a different name.

The scaling policy type.

The following policy types are supported:

`TargetTrackingScaling` —Not supported for Amazon EMR

`StepScaling` —Not supported for DynamoDB, Amazon Comprehend, Lambda, Amazon Keyspaces, Amazon MSK, Amazon ElastiCache, or Neptune.

`PredictiveScaling` —Only supported for Amazon ECS

policyType

The predictive scaling policy configuration.

predictiveScalingPolicyConfiguration

The identifier of the resource associated with the scaling policy.

This string consists of the resource type and unique identifier.

- ECS service - The resource type is `service` and the unique identifier is the cluster name and service name. Example: `service/my-cluster/my-service` .
- Spot Fleet - The resource type is `spot-fleet-request` and the unique identifier is the Spot Fleet request ID. Example: `spot-fleet-request/sfr-73fbd2ce-aa30-494c-8788-1cee4EXAMPLE` .
- EMR cluster - The resource type is `instancegroup` and the unique identifier is the cluster ID and instance group ID. Example: `instancegroup/j-2EEZNYKUA1NTV/ig-1791Y4E1L8YI0` .
- AppStream 2.0 fleet - The resource type is `fleet` and the unique identifier is the fleet name. Example: `fleet/sample-fleet` .
- DynamoDB table - The resource type is `table` and the unique identifier is the table name. Example: `table/my-table` .
- DynamoDB global secondary index - The resource type is `index` and the unique identifier is the index name. Example: `table/my-table/index/my-table-index` .
- Aurora DB cluster - The resource type is `cluster` and the unique identifier is the cluster name. Example: `cluster:my-db-cluster` .
- SageMaker endpoint variant - The resource type is `variant` and the unique identifier is the resource ID. Example: `endpoint/my-end-point/variant/KMeansClustering` .
- Custom resources are not supported with a resource type. This parameter must specify the `OutputValue` from the CloudFormation template stack used to access the resources. The unique identifier is defined by the service provider. More information is available in our [GitHub repository](https://docs.aws.amazon.com/https://github.com/aws/aws-auto-scaling-custom-resource) .
- Amazon Comprehend document classification endpoint - The resource type and unique identifier are specified using the endpoint ARN. Example: `arn:aws:comprehend:us-west-2:123456789012:document-classifier-endpoint/EXAMPLE` .
- Amazon Comprehend entity recognizer endpoint - The resource type and unique identifier are specified using the endpoint ARN. Example: `arn:aws:comprehend:us-west-2:123456789012:entity-recognizer-endpoint/EXAMPLE` .
- Lambda provisioned concurrency - The resource type is `function` and the unique identifier is the function name with a function version or alias name suffix that is not `$LATEST` . Example: `function:my-function:prod` or `function:my-function:1` .
- Amazon Keyspaces table - The resource type is `table` and the unique identifier is the table name. Example: `keyspace/mykeyspace/table/mytable` .
- Amazon MSK cluster - The resource type and unique identifier are specified using the cluster ARN. Example: `arn:aws:kafka:us-east-1:123456789012:cluster/demo-cluster-1/6357e0b2-0e6a-4b86-a0b4-70df934c2e31-5` .
- Amazon ElastiCache replication group - The resource type is `replication-group` and the unique identifier is the replication group name. Example: `replication-group/mycluster` .
- Amazon ElastiCache cache cluster - The resource type is `cache-cluster` and the unique identifier is the cache cluster name. Example: `cache-cluster/mycluster` .
- Neptune cluster - The resource type is `cluster` and the unique identifier is the cluster name. Example: `cluster:mycluster` .
- SageMaker serverless endpoint - The resource type is `variant` and the unique identifier is the resource ID. Example: `endpoint/my-end-point/variant/KMeansClustering` .
- SageMaker inference component - The resource type is `inference-component` and the unique identifier is the resource ID. Example: `inference-component/my-inference-component` .
- Pool of WorkSpaces - The resource type is `workspacespool` and the unique identifier is the pool ID. Example: `workspacespool/wspool-123456` .

The scalable dimension. This string consists of the service namespace, resource type, and scaling property.

- `ecs:service:DesiredCount` - The task count of an ECS service.
- `elasticmapreduce:instancegroup:InstanceCount` - The instance count of an EMR Instance Group.
- `ec2:spot-fleet-request:TargetCapacity` - The target capacity of a Spot Fleet.
- `appstream:fleet:DesiredCapacity` - The capacity of an AppStream 2.0 fleet.
- `dynamodb:table:ReadCapacityUnits` - The provisioned read capacity for a DynamoDB table.
- `dynamodb:table:WriteCapacityUnits` - The provisioned write capacity for a DynamoDB table.
- `dynamodb:index:ReadCapacityUnits` - The provisioned read capacity for a DynamoDB global secondary index.
- `dynamodb:index:WriteCapacityUnits` - The provisioned write capacity for a DynamoDB global secondary index.
- `rds:cluster:ReadReplicaCount` - The count of Aurora Replicas in an Aurora DB cluster. Available for Aurora MySQL-compatible edition and Aurora PostgreSQL-compatible edition.
- `sagemaker:variant:DesiredInstanceCount` - The number of EC2 instances for a SageMaker model endpoint variant.
- `custom-resource:ResourceType:Property` - The scalable dimension for a custom resource provided by your own application or service.
- `comprehend:document-classifier-endpoint:DesiredInferenceUnits` - The number of inference units for an Amazon Comprehend document classification endpoint.
- `comprehend:entity-recognizer-endpoint:DesiredInferenceUnits` - The number of inference units for an Amazon Comprehend entity recognizer endpoint.
- `lambda:function:ProvisionedConcurrency` - The provisioned concurrency for a Lambda function.
- `cassandra:table:ReadCapacityUnits` - The provisioned read capacity for an Amazon Keyspaces table.
- `cassandra:table:WriteCapacityUnits` - The provisioned write capacity for an Amazon Keyspaces table.
- `kafka:broker-storage:VolumeSize` - The provisioned volume size (in GiB) for brokers in an Amazon MSK cluster.
- `elasticache:cache-cluster:Nodes` - The number of nodes for an Amazon ElastiCache cache cluster.
- `elasticache:replication-group:NodeGroups` - The number of node groups for an Amazon ElastiCache replication group.
- `elasticache:replication-group:Replicas` - The number of replicas per node group for an Amazon ElastiCache replication group.
- `neptune:cluster:ReadReplicaCount` - The count of read replicas in an Amazon Neptune DB cluster.
- `sagemaker:variant:DesiredProvisionedConcurrency` - The provisioned concurrency for a SageMaker serverless endpoint.
- `sagemaker:inference-component:DesiredCopyCount` - The number of copies across an endpoint for a SageMaker inference component.
- `workspaces:workspacespool:DesiredUserSessions` - The number of user sessions for the WorkSpaces in the pool.

The CloudFormation-generated ID of an Application Auto Scaling scalable target.

For more information about the ID, see the Return Value section of the `AWS::ApplicationAutoScaling::ScalableTarget` resource.

> You must specify either the `ScalingTargetId` property, or the `ResourceId` , `ScalableDimension` , and `ServiceNamespace` properties, but not both.

AWS applicationautoscaling

L2 Constructs4

ScalableTarget

StepScalingAction

StepScalingPolicy

TargetTrackingScalingPolicy

L1 Constructs2

CfnScalableTarget

CfnScalingPolicy

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