COA OpenStack Heat & Orchestration 1 — Questions and Answers
Question 1: What is the primary purpose of OpenStack Heat?
- To monitor OpenStack resource usage and generate alerts
- To orchestrate composite cloud applications using templates (Correct answer)
- To manage virtual machine snapshots and backups
- To provide DNS resolution for OpenStack instances
Correct answer: To orchestrate composite cloud applications using templates
Heat is OpenStack's orchestration service that allows users to describe and automate the deployment of composite cloud applications using templates.
Question 2: Which template format is the native format for OpenStack Heat templates?
- AWS CloudFormation Template (CFN)
- Heat Orchestration Template (HOT) (Correct answer)
- YAML Ain't Markup Language (YAML-only)
- JavaScript Object Notation (JSON-only)
Correct answer: Heat Orchestration Template (HOT)
HOT (Heat Orchestration Template) is the native format for Heat, designed specifically for OpenStack and supporting all Heat features.
Question 3: What is a 'stack' in the context of OpenStack Heat?
- A group of compute hosts sharing the same hardware
- A collection of resources instantiated from a Heat template (Correct answer)
- A network topology connecting multiple tenants
- A queue of pending resource provisioning jobs
Correct answer: A collection of resources instantiated from a Heat template
A Heat stack is the collection of resources (instances, networks, volumes, etc.) that are created and managed together based on a template.
Question 4: Which top-level section of a HOT template defines the version of the template format?
- format_version
- heat_template_version (Correct answer)
- template_version
- openstack_version
Correct answer: heat_template_version
The 'heat_template_version' field is mandatory and specifies which version of the HOT format the template conforms to (e.g., 2021-04-16).
Question 5: In a HOT template, what section is used to declare inputs that can be customized at stack creation time?
- inputs
- parameters (Correct answer)
- variables
- arguments
Correct answer: parameters
The 'parameters' section defines user-customizable values that are passed into the template when creating or updating a stack.
Question 6: Which Heat CLI command is used to create a new stack from a template file?
- heat stack-create
- openstack stack create (Correct answer)
- openstack heat deploy
- heat template-apply
Correct answer: openstack stack create
The modern OpenStack CLI uses 'openstack stack create' to instantiate a new Heat stack from a template.
Question 7: What does the 'outputs' section of a HOT template provide?
- Logging destinations for resource events
- Values returned to the user after stack creation, such as IP addresses (Correct answer)
- Error messages generated during template validation
- Metric data exported to Ceilometer
Correct answer: Values returned to the user after stack creation, such as IP addresses
The 'outputs' section defines key-value pairs that are returned to the user after the stack is created, commonly used to expose resource attributes like IP addresses or URLs.
COA OpenStack Heat & Orchestration 1
What is the primary purpose of OpenStack Heat?