OpenStack Orchestration (Heat) Flashcards

What file format does OpenStack Heat use to define infrastructure templates?

Answer: YAML or JSON

Heat Orchestration Templates (HOT) support both YAML and JSON formats, with YAML being the most commonly used.

What is the top-level key required in every Heat Orchestration Template (HOT)?

Answer: heat_template_version

Every HOT file must begin with the 'heat_template_version' key, which indicates the HOT version being used.

In OpenStack Heat, what is a 'stack'?

Answer: A collection of OpenStack resources created and managed as a single unit

A Heat stack is a set of OpenStack resources (VMs, networks, volumes, etc.) that are created, updated, and deleted together as one deployable unit.

Which Heat resource type is used to create a Nova compute instance?

Answer: OS::Nova::Server

OS::Nova::Server is the Heat resource type used to provision a Nova compute instance within a template.

What is the purpose of the 'parameters' section in a Heat template?

Answer: To define user-supplied inputs that customize the stack at launch time

The 'parameters' section allows template authors to define inputs that users provide when creating a stack, making templates reusable.

Which Heat function is used to reference another resource within the same template?

Answer: get_resource

'get_resource' is the intrinsic function used to reference another resource defined within the same Heat template.

What does the Heat 'outputs' section provide?

Answer: Values returned to the user after a stack is created, such as IP addresses or URLs

The 'outputs' section defines values Heat exposes to the user after stack creation, such as instance IP addresses or endpoints.