by shigemk2

当面は技術的なことしか書かない

RegisterScalableTargetInputのRoleArn

サービスリンクロールに対応してるサービスならRoleArnは不要だが、EMRみたいにサービスリンクロール未対応ならRoleArnが必要。

   // This parameter is required for services that do not support service-linked
    // roles (such as Amazon EMR), and it must specify the ARN of an IAM role that
    // allows Application Auto Scaling to modify the scalable target on your behalf. If
    // the service supports service-linked roles, Application Auto Scaling uses a
    // service-linked role, which it creates if it does not yet exist. For more
    // information, see Application Auto Scaling IAM roles (https://docs.aws.amazon.com/autoscaling/application/userguide/security_iam_service-with-iam.html#security_iam_service-with-iam-roles)
    // .

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