This is official Amazon Web Services (AWS) Prescriptive Guidance documentation that describes an automated patching solution that uses AWS Systems Manager. You can use this solution to patch both your non-immutable (long-running) Amazon Elastic Compute Cloud (Amazon EC2) instances that span multiple AWS accounts and AWS Regions, and your on-premises instances. The content is offered here as a free Kindle book, or you can read it online or in PDF format; see