OpenStack Core Components 5

Question 1

What is the role of the 'neutron-l3-agent' in an OpenStack deployment?

Accepted Answer

Provides Layer 3 routing and floating IP NAT between networks

Answer

The neutron-l3-agent manages virtual routers on network nodes, performing routing between tenant subnets and NAT for floating IPs.

Question 2

In OpenStack, what does 'live migration' allow an operator to do?

Accepted Answer

Transfer a running VM from one compute host to another with minimal interruption

Answer

Live migration moves a running instance between compute hosts while it continues to serve traffic, useful for host maintenance.

Question 3

Which storage protocol is most commonly used when attaching a Cinder volume to a Nova instance in production?

Accepted Answer

iSCSI

Answer

iSCSI is the most widely used protocol for attaching Cinder block volumes to Nova instances, transporting SCSI commands over TCP/IP.

Question 4

What is the purpose of a Glance 'image property' (metadata)?

Accepted Answer

Storing key-value pairs that describe the image and influence scheduler behavior

Answer

Glance image properties are arbitrary key-value metadata attached to images that can influence Nova scheduling, driver behavior, and filtering.

Question 5

Which OpenStack service provides auto-scaling and orchestration of application stacks?

Accepted Answer

Heat

Answer

Heat provides stack orchestration and supports auto-scaling policies via integration with Ceilometer/Aodh to grow or shrink resource groups.

OpenStack Practice Test