CreateTaskSet - Amazon Elastic Container Service


Create a task set in the specified cluster and service. This is used when a service uses the EXTERNAL deployment controller type. For more information, see Amazon ECS deployment types in the Amazon Elastic Container Service Developer Guide.


On March 21, 2024, a change was made to resolve the task definition revision before authorization. When a task definition revision is not specified, authorization will occur using the latest revision of a task definition.

For information about the maximum number of task sets and otther quotas, see Amazon ECS service quotas in the Amazon Elastic Container Service Developer Guide.

Request Syntax

{ "capacityProviderStrategy": [ { "base": number, "capacityProvider": "string", "weight": number } ], "clientToken": "string", "cluster": "string", "externalId": "string", "launchType": "string", "loadBalancers": [ { "containerName": "string", "containerPort": number, "loadBalancerName": "string", "targetGroupArn": "string" } ], "networkConfiguration": { "awsvpcConfiguration": { "assignPublicIp": "string", "securityGroups": [ "string" ], "subnets": [ "string" ] } }, "platformVersion": "string", "scale": { "unit": "string", "value": number }, "service": "string", "serviceRegistries": [ { "containerName": "string", "containerPort": number, "port": number, "registryArn": "string" } ], "tags": [ { "key": "string", "value": "string" } ], "taskDefinition": "string" }

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.


The capacity provider strategy to use for the task set.

A capacity provider strategy consists of one or more capacity providers along with the base and weight to assign to them. A capacity provider must be associated with the cluster to be used in a capacity provider strategy. The PutClusterCapacityProviders API is used to associate a capacity provider with a cluster. Only capacity providers with an ACTIVE or UPDATING status can be used.

If a capacityProviderStrategy is specified, the launchType parameter must be omitted. If no capacityProviderStrategy or launchType is specified, the defaultCapacityProviderStrategy for the cluster is used.

If specifying a capacity provider that uses an Auto Scaling group, the capacity provider must already be created. New capacity providers can be created with the CreateCapacityProvider API operation.

To use a AWS Fargate capacity provider, specify either the FARGATE or FARGATE_SPOT capacity providers. The AWS Fargate capacity providers are available to all accounts and only need to be associated with a cluster to be used.

The PutClusterCapacityProviders API operation is used to update the list of available capacity providers for a cluster after the cluster is created.

Type: Array of CapacityProviderStrategyItem objects

Required: No


An identifier that you provide to ensure the idempotency of the request. It must be unique and is case sensitive. Up to 36 ASCII characters in the range of 33-126 (inclusive) are allowed.

Type: String

Required: No


The short name or full Amazon Resource Name (ARN) of the cluster that hosts the service to create the task set in.

Type: String

Required: Yes


An optional non-unique tag that identifies this task set in external systems. If the task set is associated with a service discovery registry, the tasks in this task set will have the ECS_TASK_SET_EXTERNAL_ID AWS Cloud Map attribute set to the provided value.

Type: String

Required: No


The launch type that new tasks in the task set uses. For more information, see Amazon ECS launch types in the Amazon Elastic Container Service Developer Guide.

If a launchType is specified, the capacityProviderStrategy parameter must be omitted.

Type: String

Valid Values: EC2 | FARGATE | EXTERNAL

Required: No


A load balancer object representing the load balancer to use with the task set. The supported load balancer types are either an Application Load Balancer or a Network Load Balancer.

Type: Array of LoadBalancer objects

Required: No


An object representing the network configuration for a task set.

Type: NetworkConfiguration object

Required: No


The platform version that the tasks in the task set uses. A platform version is specified only for tasks using the Fargate launch type. If one isn't specified, the LATEST platform version is used.

Type: String

Required: No


A floating-point percentage of the desired number of tasks to place and keep running in the task set.

Type: Scale object

Required: No


The short name or full Amazon Resource Name (ARN) of the service to create the task set in.

Type: String

Required: Yes


The details of the service discovery registries to assign to this task set. For more information, see Service discovery.

Type: Array of ServiceRegistry objects

Required: No


The metadata that you apply to the task set to help you categorize and organize them. Each tag consists of a key and an optional value. You define both. When a service is deleted, the tags are deleted.

The following basic restrictions apply to tags:

  • Maximum number of tags per resource - 50

  • For each resource, each tag key must be unique, and each tag key can have only one value.

  • Maximum key length - 128 Unicode characters in UTF-8

  • Maximum value length - 256 Unicode characters in UTF-8

  • If your tagging schema is used across multiple services and resources, remember that other services may have restrictions on allowed characters. Generally allowed characters are: letters, numbers, and spaces representable in UTF-8, and the following characters: + - = . _ : / @.

  • Tag keys and values are case-sensitive.

  • Do not use aws:, AWS:, or any upper or lowercase combination of such as a prefix for either keys or values as it is reserved for AWS use. You cannot edit or delete tag keys or values with this prefix. Tags with this prefix do not count against your tags per resource limit.

Type: Array of Tag objects

Array Members: Minimum number of 0 items. Maximum number of 50 items.

Required: No


The task definition for the tasks in the task set to use. If a revision isn't specified, the latest ACTIVE revision is used.

Type: String

Required: Yes

Response Syntax

{ "taskSet": { "capacityProviderStrategy": [ { "base": number, "capacityProvider": "string", "weight": number } ], "clusterArn": "string", "computedDesiredCount": number, "createdAt": number, "externalId": "string", "id": "string", "launchType": "string", "loadBalancers": [ { "containerName": "string", "containerPort": number, "loadBalancerName": "string", "targetGroupArn": "string" } ], "networkConfiguration": { "awsvpcConfiguration": { "assignPublicIp": "string", "securityGroups": [ "string" ], "subnets": [ "string" ] } }, "pendingCount": number, "platformFamily": "string", "platformVersion": "string", "runningCount": number, "scale": { "unit": "string", "value": number }, "serviceArn": "string", "serviceRegistries": [ { "containerName": "string", "containerPort": number, "port": number, "registryArn": "string" } ], "stabilityStatus": "string", "stabilityStatusAt": number, "startedBy": "string", "status": "string", "tags": [ { "key": "string", "value": "string" } ], "taskDefinition": "string", "taskSetArn": "string", "updatedAt": number } }

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.


Information about a set of Amazon ECS tasks in either an AWS CodeDeploy or an EXTERNAL deployment. A task set includes details such as the desired number of tasks, how many tasks are running, and whether the task set serves production traffic.

Type: TaskSet object


For information about the errors that are common to all actions, see Common Errors.


You don't have authorization to perform the requested action.

HTTP Status Code: 400


These errors are usually caused by a client action. This client action might be using an action or resource on behalf of a user that doesn't have permissions to use the action or resource. Or, it might be specifying an identifier that isn't valid.

HTTP Status Code: 400


The specified cluster wasn't found. You can view your available clusters with ListClusters. Amazon ECS clusters are Region specific.

HTTP Status Code: 400


The specified parameter isn't valid. Review the available parameters for the API request.

HTTP Status Code: 400


The specified namespace wasn't found.

HTTP Status Code: 400


The specified platform version doesn't satisfy the required capabilities of the task definition.

HTTP Status Code: 400


The specified platform version doesn't exist.

HTTP Status Code: 400


These errors are usually caused by a server issue.

HTTP Status Code: 500


The specified service isn't active. You can't update a service that's inactive. If you have previously deleted a service, you can re-create it with CreateService.

HTTP Status Code: 400


The specified service wasn't found. You can view your available services with ListServices. Amazon ECS services are cluster specific and Region specific.

HTTP Status Code: 400


The specified task isn't supported in this Region.

HTTP Status Code: 400

See Also

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