CloudFormation

Question 1

What are main cloudformation templates components?

Answer 1

Resources
* Represent AWS components
Parameters
* provide inputs to the AWS templates
Mappings
* dict
Outputs
* declares optional outputs values that we can import into other stacks
Conditions
* controls the creation of resources based on conditions

Question 2

What are the cloudformation intrinsic functions?

Answer 2

Fn::Ref
* reference parameter - returns the value
Fn::GetAtt
* get attribute of a resource
Fn::FindInMap
* return a value from a specified key
Fn::Join
* join values with a delimiter
Fn::Sub
* substitutes value

Question 3

When cloudformation performs a rollback?

Answer 3

When stack creation fails - everything rolls back
When stack update fails - rolls back to previous known working state

Question 4

What is a cloudformation drift?

Answer 4

A drift happens when a resource defined in cloudformation is changed outside it. These changes are displayed on AWS console and can be undone.