Share Amazon Route 53 Application Recovery Controller clusters across multiple AWS accounts

You can now use [AWS Resource Access Manager](https://aws.amazon.com/ram/) (AWS RAM) to share cluster resources across accounts in [Amazon Route 53 Application Recovery Controller](https://aws.amazon.com/route53/application-recovery-controller/) (Route 53 ARC). A cluster in Route 53 ARC is a set of five redundant endpoints in separate AWS Regions that you can use with API calls to manage failover for your multi-Region applications. When you opt to share a cluster across AWS accounts in your organization, teams can set up and operate failover controls using the same cluster independently. AWS RAM is a service that helps AWS customers to securely share resources across AWS accounts. With AWS RAM, you can share resources within an organization or organizational units (OUs) in AWS Organizations. Sharing clusters in Route 53 ARC can help you to reduce the number of total clusters that your organization requires, and AWS RAM is a centralized and controlled way to share a cluster. By sharing one or more clusters across different teams, you can maximize the benefits of Route 53 ARC with fewer clusters and lower cost overall. Sharing clusters across accounts can also ease the process of onboarding multiple applications to Route 53 ARC, especially if you have a large number of applications distributed across several accounts and operations teams. There is no additional charge for sharing clusters in Route 53 ARC using AWS RAM. To get started setting up shared clusters, read the [documentation](https://docs.aws.amazon.com/r53recovery/latest/dg/routing-control.failover-different-accounts.html).