AWS Resource Access Manager (RAM)
- What it is
- Share AWS resources across accounts (or across an Organization) without duplicating them and without cross-account roles.
- What can be shared
- VPC subnets, Transit Gateways, Route 53 Resolver rules, AWS License Manager configurations, AWS Certificate Manager (ACM) Private CA, Aurora DB clusters.
- Why it saves money
- One central VPC and one Transit Gateway serve many accounts instead of one per account. Fewer NAT gateways, fewer peering connections.
- Not to be confused with
- IAM cross-account roles — grant API permissions to act in another account. RAM shares the resource itself so it appears natively in the consumer account.
- AWS Organizations — the account structure; RAM shares resources within it.