About
A cloudformation stack is a collection of AWS resources that you can manage as a single unit.
You manage related resources as a single unit called a stack.
Management
All the resources in a stack are defined by the Aws - Cloudformation (CFN).
You create, update, and delete a collection of resources by creating, updating, and deleting stacks.
- Create: You create a stack by submitting a template. If a resource cannot be created, AWS CloudFormation rolls the stack back and automatically deletes any resources that were created.
- Delete: If a resource cannot be deleted, any remaining resources are retained until the stack can be successfully deleted.
- Update: If you need to make changes to the running resources in a stack, you update the stack. Before making changes to your resources, you can generate a change set, which is a summary of your proposed changes. If you change the name of an Amazon RDS database instance, AWS CloudFormation will create a new database and delete the old one. You will lose the data in the old database unless you've already backed it up. Updating doc
Example
- A stack, for instance, can include all the resources required to run a web application, such as a web server, a database, and networking rules. If you no longer require that web application, you can simply delete the stack, and all of its related resources are deleted.