...Rely on high-quality infrastructure templates: peer-reviewed by an expert (certified AWS solutions architect Professional) and verified with automated tests. You can apply updates to an existing stack with an updated template. CloudFormation will figure out what needs to be changed. Never make manual changes to infrastructure managed by CloudFormation! The bastion host has a optional dependency on the alert stack. So if you want to receive alerts if your bastion hosts is in trouble, supply an alert stack. Do you want to accelerate your start with AWS CloudFormation and our templates? ...