Spot Instances for cost savings in AWS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an AWS Spot Instance?

An AWS Spot Instance is a type of virtual server that uses spare AWS capacity at a lower price. It can be interrupted by AWS when the capacity is needed elsewhere.

beginner

Why are Spot Instances cheaper than On-Demand Instances?

Spot Instances are cheaper because they use unused AWS capacity that can be taken back anytime. This makes them less reliable but much more cost-effective.

intermediate

What happens when AWS reclaims a Spot Instance?

AWS sends a two-minute warning before interrupting the Spot Instance. The instance is then terminated or stopped, so workloads must handle interruptions gracefully.

intermediate

Name one best practice when using Spot Instances for cost savings.

Use Spot Instances for flexible, fault-tolerant workloads like batch jobs or stateless applications that can handle interruptions.

advanced

How can you protect critical workloads when using Spot Instances?

Combine Spot Instances with On-Demand or Reserved Instances to ensure availability and use Spot for cost savings on flexible parts of your workload.

What is the main reason Spot Instances are cheaper than On-Demand Instances?

A They run slower

B They have better hardware

C They use spare AWS capacity that can be reclaimed

D They come with longer contracts

Spot Instances use spare AWS capacity that can be taken back, which lowers their price.

How much warning time does AWS provide before reclaiming a Spot Instance?

A 2 minutes

B 30 seconds

C 10 minutes

D No warning

AWS provides a two-minute warning before interrupting a Spot Instance.

Which workload is best suited for Spot Instances?

A Stateless batch processing jobs

B Critical database servers

C Real-time financial transactions

D Long-term storage

Stateless batch jobs can handle interruptions and are ideal for Spot Instances.

What should you do to ensure availability when using Spot Instances?

A Use only Spot Instances

B Avoid using Spot Instances

C Use Spot Instances for all workloads

D Mix Spot with On-Demand or Reserved Instances

Mixing Spot with On-Demand or Reserved Instances helps maintain availability.

What is a key risk of using Spot Instances?

A Higher cost

B Instances can be interrupted anytime

C Limited geographic regions

D No access to AWS support

Spot Instances can be interrupted by AWS when capacity is needed elsewhere.

Explain how Spot Instances help reduce cloud costs and what trade-offs they involve.

Think about why AWS offers these instances cheaper and what you must plan for.

Describe a strategy to use Spot Instances safely in a production environment.

Consider how to balance cost savings with reliability.