Spot VMs for cost savings in Azure - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Spot VM eviction behavior

You deploy an Azure Spot VM to save costs. What happens when Azure needs the capacity back?

A The Spot VM is immediately deallocated without warning.

B The Spot VM continues running until you manually stop it.

C The Spot VM automatically converts to a standard VM without interruption.

D The Spot VM receives a notification and is evicted after a short time.

💡 Hint

Think about how Azure informs you before stopping a Spot VM.

Azure Spot VMs receive a notification before eviction, allowing a short time to save state or gracefully shut down.

❓ Architecture

intermediate

Designing a resilient app with Spot VMs

You want to use Spot VMs for batch processing but avoid job failures when VMs are evicted. Which architecture best supports this?

A Combine Spot VMs with standard VMs in a scale set and use a queue to track jobs.

B Deploy Spot VMs without any monitoring or retry logic.

C Use only standard VMs to avoid eviction interruptions.

D Use Spot VMs with no backup and restart jobs manually if evicted.

💡 Hint

Think about how to handle interruptions automatically.

Combining Spot and standard VMs with a queue allows jobs to be retried if Spot VMs are evicted, improving resilience.

❓ Configuration

advanced

Configuring eviction policy for Spot VMs

Which eviction policy setting allows a Spot VM to be stopped and deallocated instead of deleted upon eviction?

A Set eviction policy to 'Deallocate'.

B Set eviction policy to 'Stop'.

C Set eviction policy to 'Delete'.

D Set eviction policy to 'Retain'.

💡 Hint

Consider how to keep the VM's disk after eviction.

The 'Deallocate' eviction policy stops the VM and keeps the disk, allowing restart later.

❓ security

advanced

Security considerations for Spot VMs

What is a key security best practice when using Spot VMs in Azure?

A Disable all network security groups to improve performance.

B Allow unrestricted inbound traffic to Spot VMs for easy access.

C Use managed identities and restrict access with network security groups.

D Store all secrets directly on the Spot VM's local disk.

💡 Hint

Think about secure access and identity management.

Using managed identities and network security groups helps secure Spot VMs despite their transient nature.

❓ service_behavior

expert

Spot VM pricing and availability behavior

Which statement correctly describes how Azure Spot VM pricing and availability behave?

A Spot VM prices are fixed and availability is guaranteed 24/7.

B Spot VM prices vary based on supply and demand, and availability can be interrupted anytime.

C Spot VMs automatically switch to standard VMs when prices rise.

D Spot VMs have a monthly quota limiting usage, but prices never change.

💡 Hint

Consider how cloud providers manage excess capacity.

Spot VM prices fluctuate with supply and demand, and VMs can be evicted when capacity is needed.