What is the MOST secure solution?
Create a new IAM role with the same user name as the Amazon Redshift developer user ID. Provide the IAM role with read-only access to Amazon S3 with the assume role action.
Create a new IAM role with read-only access to the Amazon S3 bucket and include the assume role action. Modify the Amazon Redshift cluster to add the IAM role.
Create a new IAM role with read-only access to the Amazon S3 bucket with the assume role action. Add this role to the developer IAM user ID used for the copy job that ended with an error message.
Create a new IAM user with access keys and a new role with read-only access to the Amazon S3 bucket. Add this role to the Amazon Redshift cluster. Change the copy job to use the access keys created.
Explanations:
Creating an IAM role with the same username as the Redshift user does not address the required permissions for Redshift to access the S3 bucket. The Redshift cluster itself needs to be assigned a role with permissions.
This solution provides the necessary read-only access to the S3 bucket via an IAM role, and attaches this role to the Redshift cluster. This ensures that Redshift can assume the role to access S3.
Attaching the IAM role directly to the developer IAM user will not allow Redshift to access S3. Redshift requires a role assigned at the cluster level, not on individual users.
Creating a new IAM user and access keys is not necessary and adds complexity. IAM roles for Redshift are the preferred method to handle permissions for accessing S3.
I calculate that the answer is:
Create a new IAM role with read-only access to the Amazon S3 bucket and include the assume role action. Modify the Amazon Redshift cluster to add the IAM role.