Amazon ECS is integrated with, and makes use of, several other AWS services, including Elastic Load Balancing and EC2. ECS makes use of service-linked roles, which are special types of roles associated with a service to provide access to the required AWS services without additional configuration. ECS makes use of the AWSServiceRoleForECS role to access other AWS services for managing EC2 network interfaces, registering/deregistering instances from a load balancer, and registering targets. A root user does not require any additional configuration to be able to use ECS with Fargate.
Problem: An IAM user does not have permission to create or modify ECS resources or invoke the ECS API by default. An IAM user also does not have permissions to use the ECS Console or the AWS CLI.
Solution: An IAM user must be granted permission to create the AWSServiceRoleForECS role...