COA Identity, Image, and Compute Management 1 — Questions and Answers
Question 1: What is the primary function of Keystone in OpenStack?
- Image storage
- Block storage
- Identity and access management (Correct answer)
- Network provisioning
Correct answer: Identity and access management
Keystone is the central identity service for OpenStack, handling authentication and authorization for all components. It manages users, projects (tenants), and roles, ensuring secure access control and single sign-on capabilities across the entire OpenStack deployment.
Question 2: Which OpenStack service is responsible for managing virtual machine images?
- Neutron
- Glance (Correct answer)
- Cinder
- Keystone
Correct answer: Glance
Glance is the image service in OpenStack, specifically designed to manage virtual machine images. It provides a catalog where users can store, discover, and retrieve various operating system images, which are then used by Nova to launch new instances.
Question 3: Which component manages the lifecycle of compute instances in OpenStack?
- Glance
- Horizon
- Nova (Correct answer)
- Swift
Correct answer: Nova
Nova is the core compute service in OpenStack, responsible for the entire lifecycle management of virtual machine instances. This includes provisioning, scheduling, launching, monitoring, and terminating instances, making it central to the compute capabilities of OpenStack.
Question 4: What is required before launching a new instance in OpenStack?
- An SSH key only
- A block storage volume
- Image, flavor, and network settings (Correct answer)
- Floating IPs and snapshots
Correct answer: Image, flavor, and network settings
To launch an OpenStack instance, you need an image (the operating system template), a flavor (defining compute resources like CPU, RAM, and disk size), and network settings (to connect the instance to a virtual network). These three elements are fundamental for defining and deploying a functional virtual machine.
Question 5: How are users authenticated in OpenStack?
- Via direct access to the database
- By floating IPs
- Using Keystone-issued tokens (Correct answer)
- Through volume creation
Correct answer: Using Keystone-issued tokens
OpenStack uses Keystone as its identity service, which authenticates users and issues temporary tokens upon successful login. These tokens are then used to authorize subsequent API requests to other OpenStack services, ensuring secure and consistent access control across the cloud.
Question 6: Which OpenStack component defines the compute flavors?
- Cinder
- Glance
- Nova (Correct answer)
- Swift
Correct answer: Nova
Nova, the compute service, is responsible for defining and managing flavors, which are pre-defined templates for virtual machine resource allocation. Flavors specify the amount of vCPUs, RAM, and root disk size an instance will receive, allowing users to choose appropriate compute capacities.
COA Identity, Image, and Compute Management 1
What is the primary function of Keystone in OpenStack?