Attaches the specified managed policy to the specified IAM role. When you attach a managed policy to a role, the managed policy becomes part of the role's permission (access) policy.
You cannot use a managed policy as the role's trust policy. The role's trust policy is created at the same time as the role, using CreateRole. You can update a role's trust policy using UpdateAssumeRolePolicy.
Use this operation to attach a managed policy to a role. To embed an inline policy in a role, use PutRolePolicy. For more information about policies, see Managed policies and inline policies in the IAM User Guide.
As a best practice, you can validate your IAM policies. To learn more, see Validating IAM policies in the IAM User Guide.