Using service-linked roles for VPC

Amazon VPC uses AWS Identity and Access Management (IAM) service-linked roles. A service-linked role is a unique type of IAM role that is linked directly to VPC. Service-linked roles are predefined by VPC and include all the permissions that the service requires to call other AWS services on your behalf.

A service-linked role makes setting up VPC easier because you don't have to manually add the necessary permissions. VPC defines the permissions of its service-linked roles, and unless defined otherwise, only VPC 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 their related resources. This protects your VPC resources because you can't inadvertently remove permission to access the resources.

For information about other services that support service-linked roles, see AWS services that work with IAM 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 VPC

VPC uses the service-linked role named AWSServiceRoleForNATGateway – This service-linked role enables Amazon VPC to allocate Elastic IP addresses on your behalf to automatically scale regional NAT Gateways, to associate and disassociate your existing Elastic IPs to regional NAT Gateways at your request, and to describe Network Interfaces to identify your existing infrastructure to automatically expand into new Availability Zones.

The AWSServiceRoleForNATGateway service-linked role trusts the following services to assume the role:

The role permissions policy named AWSNATGatewayServiceRolePolicy allows VPC to complete the following actions on the specified 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 in the IAM User Guide.

Creating a service-linked role for VPC

You don't need to manually create a service-linked role. When you create a NAT Gateway with a "regional" Availability Mode in the AWS Management Console, the AWS CLI, or the AWS API, VPC creates the service-linked role for you.

If you delete this service-linked role, and then need to create it again, you can use the same process to recreate the role in your account. When you create a NAT Gateway with a "regional" Availability Mode, VPC creates the service-linked role for you again.

You can also use the IAM console to create a service-linked role with the AWSServiceRoleForNATGateway use case. In the AWS CLI or the AWS API, create a service-linked role with the ec2-nat-gateway.amazonaws.com service name. For more information, see Creating a service-linked role in the IAM User Guide. If you delete this service-linked role, you can use this same process to create the role again.

Editing a service-linked role for VPC

VPC does not allow you to edit the AWSServiceRoleForNATGateway 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 in the IAM User Guide.

Deleting a service-linked role for VPC

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.

To manually delete the service-linked role using IAM

Use the IAM console, the AWS CLI, or the AWS API to delete the AWSServiceRoleForNATGateway service-linked role. For more information, see Deleting a service-linked role in the IAM User Guide.

Supported Regions for VPC service-linked roles

VPC supports using service-linked roles in all of the Regions where the service is available. For more information, see AWS Regions and endpoints.

VPC does not support using service-linked roles in every Region where the service is available. You can use the AWSServiceRoleForNATGateway role in the following Regions.