Architecture and Services Flashcards

What does the OpenStack Heat service use to describe infrastructure as code?

Answer: HOT (Heat Orchestration Templates)

Heat uses its own Heat Orchestration Template (HOT) format in YAML to describe cloud infrastructure as code.

Which component handles the OpenStack Identity service's token validation in a Fernet token setup?

Answer: Symmetric keys distributed across Keystone nodes

Fernet tokens are validated using symmetric cryptographic keys that are distributed and rotated across all Keystone nodes without requiring a token database.

In OpenStack Neutron, what is an 'external network' used for?

Answer: Providing floating IPs and routing to the internet

External networks in Neutron represent the upstream network (internet-facing) from which floating IPs are allocated for external connectivity.

What is the function of the Glance registry service?

Answer: Provides a metadata catalog for images (deprecated in newer releases)

The Glance registry was a separate service for storing image metadata, though it was deprecated and its functionality merged into glance-api in newer releases.

Which OpenStack service provides key management and secrets storage?

Answer: Barbican

Barbican is the OpenStack Key Manager service that securely stores and manages secrets, keys, and certificates.

What is the primary purpose of the OpenStack Placement service?

Answer: Tracking resource provider inventories and allocations for scheduling

The Placement service tracks resource provider inventories (CPU, RAM, disk) and allocations to support Nova's scheduling decisions.

In OpenStack, which protocol does Cinder typically use to attach volumes to instances over a network?

Answer: iSCSI

Cinder commonly uses iSCSI to attach block storage volumes from the storage backend to Nova compute nodes.