Infrastructure as Code with AWS CloudFormation Flashcards

What does CloudFormation StackSets allow you to do?

Answer: Deploy stacks across multiple AWS accounts and regions simultaneously

StackSets extend CloudFormation by enabling you to create, update, or delete stacks across multiple accounts and regions with a single operation.

Which CloudFormation behavior occurs by default when a stack update fails?

Answer: Automatic rollback to the previous state

By default, CloudFormation automatically rolls back a stack to its last known stable state when an update fails.

What is the purpose of the `Fn::ImportValue` intrinsic function in CloudFormation?

Answer: To import an output value exported by another stack

Fn::ImportValue retrieves the value of an output exported by another CloudFormation stack, enabling cross-stack resource sharing.

What does CloudFormation Drift Detection identify?

Answer: Resources whose configuration has diverged from the stack template

Drift Detection compares the current configuration of stack resources with the expected configuration defined in the template, flagging any differences.

Which CloudFormation section maps keys to values, often used for environment-specific configuration like AMI IDs?

Answer: Mappings

The Mappings section defines static lookup tables keyed by region, environment, or other variables, commonly used to select region-specific AMI IDs.

What is the function of `AWS::CloudFormation::WaitCondition`?

Answer: To pause stack creation until a signal is received from an EC2 instance

WaitCondition pauses CloudFormation stack creation until it receives a specified number of success signals, typically from EC2 user data scripts.