# CfnInstanceFleetConfig Use `InstanceFleetConfig` to define instance fleets for an EMR cluster. A cluster can not use both instance fleets and instance groups. For more information, see [Configure Instance Fleets](https://docs.aws.amazon.com//emr/latest/ManagementGuide/emr-instance-group-configuration.html) in the *Amazon EMR Management Guide* . > The instance fleet configuration is available only in Amazon EMR versions 4.8.0 and later, excluding 5.0.x versions. > You can currently only add a task instance fleet to a cluster with this resource. If you use this resource, CloudFormation waits for the cluster launch to complete before adding the task instance fleet to the cluster. In order to add a task instance fleet to the cluster as part of the cluster launch and minimize delays in provisioning task nodes, use the `TaskInstanceFleets` subproperty for the [AWS::EMR::Cluster JobFlowInstancesConfig](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-elasticmapreduce-cluster-jobflowinstancesconfig.html) property instead. To use this subproperty, see [AWS::EMR::Cluster](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-elasticmapreduce-cluster.html) for examples. Extends: Construct › CfnElement › CfnRefElement › CfnResource › CfnInstanceFleetConfig Implements: IInspectable, IEnvironmentAware, IInstanceFleetConfigRef, IConstruct, IDependable - CloudFormation: [`AWS::EMR::InstanceFleetConfig`](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-resource-emr-instancefleetconfig.html) - Source: Generated code - Type last changed: v2.275.0 · 26 Oct 2026 ## Example ```ts // The code below shows an example of how to instantiate this type. // The values are placeholders you should change. import { aws_emr as emr } from 'aws-cdk-lib'; declare const configurationProperty_: emr.CfnInstanceFleetConfig.ConfigurationProperty; const cfnInstanceFleetConfig = new emr.CfnInstanceFleetConfig(this, 'MyCfnInstanceFleetConfig', { clusterId: 'clusterId', instanceFleetType: 'instanceFleetType', // the properties below are optional instanceTypeConfigs: [{ instanceType: 'instanceType', // the properties below are optional bidPrice: 'bidPrice', bidPriceAsPercentageOfOnDemandPrice: 123, configurations: [{ classification: 'classification', configurationProperties: { configurationPropertiesKey: 'configurationProperties', }, configurations: [configurationProperty_], }], customAmiId: 'customAmiId', ebsConfiguration: { ebsBlockDeviceConfigs: [{ volumeSpecification: { sizeInGb: 123, volumeType: 'volumeType', // the properties below are optional iops: 123, throughput: 123, }, // the properties below are optional volumesPerInstance: 123, }], ebsOptimized: false, }, priority: 123, weightedCapacity: 123, }], launchSpecifications: { onDemandSpecification: { allocationStrategy: 'allocationStrategy', // the properties below are optional capacityReservationOptions: { capacityReservationPreference: 'capacityReservationPreference', capacityReservationResourceGroupArn: 'capacityReservationResourceGroupArn', usageStrategy: 'usageStrategy', }, }, spotSpecification: { timeoutAction: 'timeoutAction', timeoutDurationMinutes: 123, // the properties below are optional allocationStrategy: 'allocationStrategy', blockDurationMinutes: 123, }, }, name: 'name', resizeSpecifications: { onDemandResizeSpecification: { allocationStrategy: 'allocationStrategy', capacityReservationOptions: { capacityReservationPreference: 'capacityReservationPreference', capacityReservationResourceGroupArn: 'capacityReservationResourceGroupArn', usageStrategy: 'usageStrategy', }, timeoutDurationMinutes: 123, }, spotResizeSpecification: { allocationStrategy: 'allocationStrategy', timeoutDurationMinutes: 123, }, }, targetOnDemandCapacity: 123, targetSpotCapacity: 123, }); ``` ## Initializer ```ts new CfnInstanceFleetConfig(scope: Construct, id: string, props: CfnInstanceFleetConfigProps) ``` ## Construct Props - `clusterId`: string (required) — The unique identifier of the EMR cluster. - `instanceFleetType`: string (required) — The node type that the instance fleet hosts. *Allowed Values* : TASK - `instanceTypeConfigs`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnInstanceFleetConfig.InstanceTypeConfigProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_emr.CfnInstanceFleetConfig.InstanceTypeConfigProperty.html)[] — `InstanceTypeConfigs` determine the EC2 instances that Amazon EMR attempts to provision to fulfill On-Demand and Spot target capacities. > The instance fleet configuration is available only in Amazon EMR versions 4.8.0 and later, excluding 5.0.x versions. - `launchSpecifications`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnInstanceFleetConfig.InstanceFleetProvisioningSpecificationsProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_emr.CfnInstanceFleetConfig.InstanceFleetProvisioningSpecificationsProperty.html) — The launch specification for the instance fleet. - `name`: string — The friendly name of the instance fleet. - `resizeSpecifications`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnInstanceFleetConfig.InstanceFleetResizingSpecificationsProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_emr.CfnInstanceFleetConfig.InstanceFleetResizingSpecificationsProperty.html) — The resize specification for the instance fleet. - `targetOnDemandCapacity`: number — The target capacity of On-Demand units for the instance fleet, which determines how many On-Demand instances to provision. When the instance fleet launches, Amazon EMR tries to provision On-Demand instances as specified by `InstanceTypeConfig` . Each instance configuration has a specified `WeightedCapacity` . When an On-Demand instance is provisioned, the `WeightedCapacity` units count toward the target capacity. Amazon EMR provisions instances until the target capacity is totally fulfilled, even if this results in an overage. For example, if there are 2 units remaining to fulfill capacity, and Amazon EMR can only provision an instance with a `WeightedCapacity` of 5 units, the instance is provisioned, and the target capacity is exceeded by 3 units. > If not specified or set to 0, only Spot instances are provisioned for the instance fleet using `TargetSpotCapacity` . At least one of `TargetSpotCapacity` and `TargetOnDemandCapacity` should be greater than 0. For a master instance fleet, only one of `TargetSpotCapacity` and `TargetOnDemandCapacity` can be specified, and its value must be 1. - `targetSpotCapacity`: number — The target capacity of Spot units for the instance fleet, which determines how many Spot instances to provision. When the instance fleet launches, Amazon EMR tries to provision Spot instances as specified by `InstanceTypeConfig` . Each instance configuration has a specified `WeightedCapacity` . When a Spot instance is provisioned, the `WeightedCapacity` units count toward the target capacity. Amazon EMR provisions instances until the target capacity is totally fulfilled, even if this results in an overage. For example, if there are 2 units remaining to fulfill capacity, and Amazon EMR can only provision an instance with a `WeightedCapacity` of 5 units, the instance is provisioned, and the target capacity is exceeded by 3 units. > If not specified or set to 0, only On-Demand instances are provisioned for the instance fleet. At least one of `TargetSpotCapacity` and `TargetOnDemandCapacity` should be greater than 0. For a master instance fleet, only one of `TargetSpotCapacity` and `TargetOnDemandCapacity` can be specified, and its value must be 1. ## Properties - `attrInstanceFleetId`: string — The unique identifier for instance fleet for specific cluster. - `CFN_RESOURCE_TYPE_NAME`: string (static) — The CloudFormation resource type name for this resource class. - `cfnOptions`: [ICfnResourceOptions](/cdk/api/v2/docs/aws-cdk-lib.ICfnResourceOptions.html) — Options for this resource, such as condition, update policy etc. - `cfnResourceType`: string — AWS resource type. - `clusterId`: string — The unique identifier of the EMR cluster. - `creationStack`: string[] - `env`: [ResourceEnvironment](/cdk/api/v2/docs/aws-cdk-lib.interfaces.ResourceEnvironment.html) - `instanceFleetConfigRef`: [InstanceFleetConfigReference](/cdk/api/v2/docs/aws-cdk-lib.interfaces.aws_emr.InstanceFleetConfigReference.html) — A reference to a InstanceFleetConfig resource. - `instanceFleetType`: string — The node type that the instance fleet hosts. - `instanceTypeConfigs`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnInstanceFleetConfig.InstanceTypeConfigProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_emr.CfnInstanceFleetConfig.InstanceTypeConfigProperty.html)[] — `InstanceTypeConfigs` determine the EC2 instances that Amazon EMR attempts to provision to fulfill On-Demand and Spot target capacities. - `launchSpecifications`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnInstanceFleetConfig.InstanceFleetProvisioningSpecificationsProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_emr.CfnInstanceFleetConfig.InstanceFleetProvisioningSpecificationsProperty.html) — The launch specification for the instance fleet. - `logicalId`: string — The logical ID for this CloudFormation stack element. The logical ID of the element is calculated from the path of the resource node in the construct tree. To override this value, use `overrideLogicalId(newLogicalId)`. - `name`: string — The friendly name of the instance fleet. - `node`: [Node](/cdk/api/v2/docs/constructs.Node.html) — The tree node. - `ref`: string — Return a string that will be resolved to a CloudFormation `{ Ref }` for this element. If, by any chance, the intrinsic reference of a resource is not a string, you could coerce it to an IResolvable through `Lazy.any({ produce: resource.ref })`. - `resizeSpecifications`: [IResolvable](/cdk/api/v2/docs/aws-cdk-lib.IResolvable.html) | [CfnInstanceFleetConfig.InstanceFleetResizingSpecificationsProperty](/cdk/api/v2/docs/aws-cdk-lib.aws_emr.CfnInstanceFleetConfig.InstanceFleetResizingSpecificationsProperty.html) — The resize specification for the instance fleet. - `stack`: [Stack](/cdk/api/v2/docs/aws-cdk-lib.Stack.html) — The stack in which this element is defined. CfnElements must be defined within a stack scope (directly or indirectly). - `targetOnDemandCapacity`: number — The target capacity of On-Demand units for the instance fleet, which determines how many On-Demand instances to provision. - `targetSpotCapacity`: number — The target capacity of Spot units for the instance fleet, which determines how many Spot instances to provision. ## Methods - `addDeletionOverride(path: string): void` — Syntactic sugar for `addOverride(path, undefined)`. **Parameters** - `path` — The path of the value to delete. - `addDependency(target: CfnResource): void` — Use `addResourceDependency` instead. This method has been renamed to `addResourceDependency` to more clearly set it apart from `construct.node.addDependency`. See the documentation of that function for more details. - `addDependsOn(target: CfnResource): void` — Use `addResourceDependency` instead. This can be used for resources across stacks (or nested stack) boundaries and the dependency will automatically be transferred to the relevant scope. This method has been renamed to `addResourceDependency`, which makes it more clear that this method operates at a different level from the construct-level `construct.node.addDependency()` mechanism. - `addMetadata(key: string, value: any): void` — Add a value to the CloudFormation Resource Metadata. - `addOverride(path: string, value: any): void` — Adds an override to the synthesized CloudFormation resource. To add a property override, either use `addPropertyOverride` or prefix `path` with "Properties." (i.e. `Properties.TopicName`). If the override is nested, separate each nested level using a dot (.) in the path parameter. If there is an array as part of the nesting, specify the index in the path. To include a literal `.` in the property name, prefix with a `\`. In most programming languages you will need to write this as `"\\."` because the `\` itself will need to be escaped. For example, ```typescript cfnResource.addOverride('Properties.GlobalSecondaryIndexes.0.Projection.NonKeyAttributes', ['myattribute']); cfnResource.addOverride('Properties.GlobalSecondaryIndexes.1.ProjectionType', 'INCLUDE'); ``` would add the overrides ```json "Properties": { "GlobalSecondaryIndexes": [ { "Projection": { "NonKeyAttributes": [ "myattribute" ] ... } ... }, { "ProjectionType": "INCLUDE" ... }, ] ... } ``` The `value` argument to `addOverride` will not be processed or translated in any way. Pass raw JSON values in here with the correct capitalization for CloudFormation. If you pass CDK classes or structs, they will be rendered with lowercased key names, and CloudFormation will reject the template. **Parameters** - `path` — - The path of the property, you can use dot notation to override values in complex types. - `value` — - The value. - `addPropertyDeletionOverride(propertyPath: string): void` — Adds an override that deletes the value of a property from the resource definition. **Parameters** - `propertyPath` — The path to the property. - `addPropertyOverride(propertyPath: string, value: any): void` — Adds an override to a resource property. Syntactic sugar for `addOverride("Properties.<...>", value)`. **Parameters** - `propertyPath` — The path of the property. - `value` — The value. - `addResourceDependency(target: CfnResource, reason?: string): void` — Indicates that this resource depends on another resource and cannot be provisioned unless the other resource has been successfully provisioned. This can be used for resources across stacks (or nested stack) boundaries and the dependency will automatically be transferred to the relevant scope. This method only adds dependencies between L1 resources. If you are looking for a generic construct-to-construct dependency mechanism that works for all constructs including L2s, use `construct.node.addDependency` instead. - `applyCrossStackReferenceStrength(strength: ReferenceStrength): void` — Sets the cross-stack reference strength for this resource. When set, any cross-stack reference to this resource will use the specified strength instead of the global default from the consuming stack's context. **Parameters** - `strength` — - The reference strength to use for this resource. - `applyRemovalPolicy(policy?: RemovalPolicy, options?: RemovalPolicyOptions): void` — Sets the deletion policy of the resource based on the removal policy specified. The Removal Policy controls what happens to this resource when it stops being managed by CloudFormation, either because you've removed it from the CDK application or because you've made a change that requires the resource to be replaced. The resource can be deleted (`RemovalPolicy.DESTROY`), or left in your AWS account for data recovery and cleanup later (`RemovalPolicy.RETAIN`). In some cases, a snapshot can be taken of the resource prior to deletion (`RemovalPolicy.SNAPSHOT`). A list of resources that support this policy can be found in the following link: - `cfnPropertyName(cdkPropertyName: string): string` - `getAtt(attributeName: string, typeHint?: ResolutionTypeHint): Reference` — Returns a token for an runtime attribute of this resource. Ideally, use generated attribute accessors (e.g. `resource.arn`), but this can be used for future compatibility in case there is no generated attribute. **Parameters** - `attributeName` — The name of the attribute. - `getMetadata(key: string): any` — Retrieve a value value from the CloudFormation Resource Metadata. - `inspect(inspector: TreeInspector): void` — Examines the CloudFormation resource and discloses attributes. **Parameters** - `inspector` — tree inspector to collect and process attributes. - `isCfnElement(x: any): boolean` (static) — Returns `true` if a construct is a stack element (i.e. part of the synthesized cloudformation template). Uses duck-typing instead of `instanceof` to allow stack elements from different versions of this library to be included in the same stack. **Returns:** The construct as a stack element or undefined if it is not a stack element. - `isCfnInstanceFleetConfig(x: any): boolean` (static) — Checks whether the given object is a CfnInstanceFleetConfig. - `isCfnResource(x: any): boolean` (static) — Check whether the given object is a CfnResource. - `isConstruct(x: any): boolean` (static) — Checks if `x` is a construct. Use this method instead of `instanceof` to properly detect `Construct` instances, even when the construct library is symlinked. Explanation: in JavaScript, multiple copies of the `constructs` library on disk are seen as independent, completely different libraries. As a consequence, the class `Construct` in each copy of the `constructs` library is seen as a different class, and an instance of one class will not test as `instanceof` the other class. `npm install` will not create installations like this, but users may manually symlink construct libraries together or use a monorepo tool: in those cases, multiple copies of the `constructs` library can be accidentally installed, and `instanceof` will behave unpredictably. It is safest to avoid using `instanceof`, and using this type-testing method instead. **Parameters** - `x` — Any object. **Returns:** true if `x` is an object created from a class which extends `Construct`. - `obtainDependencies(): Stack | CfnResource[]` — Retrieves an array of resources and stacks this resource depends on. For resources depended on directly, returns the `CfnResource` object. For dependencies on other stacks, returns the `Stack` object. The order of the array is not guaranteed. - `overrideLogicalId(newLogicalId: string): void` — Overrides the auto-generated logical ID with a specific ID. **Parameters** - `newLogicalId` — The new logical ID to use for this stack element. - `removeDependency(target: CfnResource): void` — Use `removeResourceDependency` instead This can be used for resources across stacks (including nested stacks) and the dependency will automatically be removed from the relevant scope. - `removeResourceDependency(target: CfnResource): void` — Indicates that this resource no longer depends on another resource. This can be used for resources across stacks (including nested stacks) and the dependency will automatically be removed from the relevant scope. - `replaceDependency(target: CfnResource, newTarget: CfnResource): void` — Replaces one dependency with another. **Parameters** - `target` — The dependency to replace. - `newTarget` — The new dependency to add. - `toString(): string` — Returns a string representation of this construct. **Returns:** a string representation of this resource - `with(...mixins: IMixin[]): IConstruct` — Applies one or more mixins to this construct. Mixins are applied in order. The list of constructs is captured at the start of the call, so constructs added by a mixin will not be visited. Use multiple `with()` calls if subsequent mixins should apply to added constructs.