OpenStack Core Components 4 — Questions and Answers
Question 1: Which OpenStack component provides container orchestration using Kubernetes clusters?
- Zun
- Magnum (Correct answer)
- Murano
- Kolla
Correct answer: Magnum
Magnum is the OpenStack Container Infrastructure Management service that provisions and manages Kubernetes clusters as a first-class resource.
Question 2: What is the default token format used by Keystone in modern OpenStack deployments?
- UUID
- PKI
- Fernet (Correct answer)
- SAML
Correct answer: Fernet
Fernet tokens are the default in modern Keystone because they are lightweight, stateless, and don't require token persistence in the database.
Question 3: In OpenStack Neutron, what is the purpose of the ML2 (Modular Layer 2) plugin?
- Managing Layer 3 routing between tenant networks
- Providing a framework to support multiple network technologies via type and mechanism drivers (Correct answer)
- Allocating IP addresses via DHCP
- Enforcing QoS bandwidth limits on ports
Correct answer: Providing a framework to support multiple network technologies via type and mechanism drivers
The ML2 plugin uses a driver framework that separates network type drivers (VLAN, VXLAN) from mechanism drivers (OVS, LinuxBridge), enabling flexible backend support.
Question 4: Which OpenStack service is used for DNS-as-a-Service?
- Barbican
- Designate (Correct answer)
- Aodh
- Panko
Correct answer: Designate
Designate is the OpenStack DNS service that manages DNS zones and records, integrating with backends like BIND and PowerDNS.
Question 5: What is a Nova 'flavor' in OpenStack?
- A pre-built VM image with a specific OS
- A hardware profile defining vCPUs, RAM, and disk for an instance (Correct answer)
- A network configuration template
- A security group policy set
Correct answer: A hardware profile defining vCPUs, RAM, and disk for an instance
Flavors define the compute resource profile (vCPUs, memory, disk) available for instantiating VMs, similar to AWS instance types.
Question 6: What mechanism does OpenStack use to provide metadata to running instances?
- A shared NFS mount at /etc/openstack
- The nova-metadata API accessible at 169.254.169.254 (Correct answer)
- Environment variables injected at boot via cloud-init only
- Direct Keystone token passed via serial console
Correct answer: The nova-metadata API accessible at 169.254.169.254
The nova-metadata service exposes instance metadata at the link-local IP 169.254.169.254, mirroring the AWS EC2 metadata endpoint convention.
Question 7: Which OpenStack project provides Key Management as a Service for storing secrets?
- Castellan
- Barbican (Correct answer)
- Vault
- Keystone
Correct answer: Barbican
Barbican is the OpenStack Key Manager service that securely stores and manages secrets like API keys, passwords, and certificates.
OpenStack Core Components 4
Which OpenStack component provides container orchestration using Kubernetes clusters?