# Service-linked roles for AWS PCS
<a name="service-linked-roles"></a>

AWS Parallel Computing Service uses AWS Identity and Access Management (IAM) [service-linked roles](https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles.html#iam-term-service-linked-role). A service-linked role is a unique type of IAM role that is linked directly to AWS PCS. Service-linked roles are predefined by AWS PCS and include all the permissions that the service requires to call other AWS services on your behalf.

A service-linked role makes setting up AWS PCS easier because you don’t have to manually add the necessary permissions. AWS PCS defines the permissions of its service-linked roles, and unless defined otherwise, only AWS PCS can assume its roles. The defined permissions include the trust policy and the permissions policy, and that permissions policy cannot be attached to any other IAM entity.

You can delete a service-linked role only after first deleting its related resources. This protects your AWS PCS resources because you can't accidentally remove permission to access the resources.

For information about other services that support service-linked roles, see [AWS services that work with IAM](https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_aws-services-that-work-with-iam.html) and look for the services that have **Yes** in the **Service-linked roles** column. Choose a **Yes** with a link to view the service-linked role documentation for that service.

## Service-linked role permissions for AWS PCS
<a name="slr-permissions"></a>

AWS PCS uses the service-linked role named **AWSServiceRoleForPCS** – Grants permission to AWS PCS to manage Amazon EC2 resources.

The AWSServiceRoleForPCS service-linked role trusts the following services to assume the role:
+ `pcs.amazonaws.com`

The role permissions policy named [AWSPCSServiceRolePolicy](security-iam-awsmanpol.md#security-iam-awsmanpol-service-role-policy) allows AWS PCS to complete actions on specific resources.

You must configure permissions to allow your users, groups, or roles to create, edit, or delete a service-linked role. For more information, see [Service-linked role permissions](https://docs.aws.amazon.com/IAM/latest/UserGuide/using-service-linked-roles.html#service-linked-role-permissions) in the *IAM User Guide*.

## Creating a service-linked role for AWS PCS
<a name="create-slr"></a>

You don't need to manually create a service-linked role. AWS PCS creates a service-linked role for you when you create a cluster.

## Editing a service-linked role for AWS PCS
<a name="edit-slr"></a>

AWS PCS does not allow you to edit the AWSServiceRoleForPCS service-linked role. After you create a service-linked role, you cannot change the name of the role because various entities might reference the role. However, you can edit the description of the role using IAM. For more information, see [Editing a service-linked role](https://docs.aws.amazon.com/IAM/latest/UserGuide/using-service-linked-roles.html#edit-service-linked-role) in the *IAM User Guide*.

## Deleting a service-linked role for AWS PCS
<a name="delete-slr"></a>

If you no longer need to use a feature or service that requires a service-linked role, we recommend that you delete that role. That way you don’t have an unused entity that is not actively monitored or maintained. However, you must clean up the resources for your service-linked role before you can manually delete it.

**Note**  
If the AWS PCS service is using the role when you try to delete the resources, then the deletion might fail. If that happens, wait for a few minutes and try the operation again.

**To remove AWS PCS resources used by the AWSServiceRoleForPCS**

You must delete all your clusters to delete the AWSServiceRoleForPCS service-linked role. For more information, see [Delete a cluster](what-is-service.md).

**To manually delete the service-linked role using IAM**

Use the IAM console, the AWS CLI, or the AWS API to delete the AWSServiceRoleForPCS service-linked role. For more information, see [Deleting a service-linked role](https://docs.aws.amazon.com/IAM/latest/UserGuide/using-service-linked-roles.html#delete-service-linked-role) in the *IAM User Guide*.

## Supported Regions for AWS PCS service-linked roles
<a name="slr-regions"></a>

AWS PCS supports using service-linked roles in all of the Regions where the service is available. For more information, see [AWS Regions and endpoints](https://docs.aws.amazon.com/general/latest/gr/rande.html).