Design for Failure and AWS Services | Exam Question Answer

Answer - A, B and C.

Each AZ is a set of one or more data centers.

By deploying your AWS resources to multiple Availability zones, you are designing with failure in mind.

So if one AZ were to go down, the other AZ's would still be up and running.

Hence your application would be more fault-tolerant.

For disaster recovery scenarios, one can move or make resources run in other regions.

And finally, one can use the Elastic Load Balancer to distribute load to multiple backend instances within a particular region.

For more information on AWS Regions and AZ's, please refer to the below URL:

http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.RegionsAndAvailabilityZones.html

The principle of "design for failure and nothing will fail" is based on the idea that system failures are inevitable and should be anticipated in the design phase, with the aim of minimizing their impact on the overall system. AWS provides a range of services and features that can support this design principle, including:

A. Availability Zones: Availability Zones are physically separate data centers within a region, designed to provide redundancy and high availability. By deploying resources across multiple Availability Zones, you can ensure that your system can continue to operate even if one zone becomes unavailable due to a natural disaster or other unexpected event.

B. Regions: Regions are separate geographic areas in which AWS provides services. Each region consists of multiple Availability Zones. By deploying resources across multiple regions, you can further increase the availability and resilience of your system, as a failure in one region will not affect resources in another region.

C. Elastic Load Balancer: Elastic Load Balancer is a service that automatically distributes incoming traffic across multiple instances or Availability Zones. By using Elastic Load Balancer, you can ensure that your system can handle increased traffic loads and that individual instances or zones do not become overloaded. This can help to prevent failures due to resource exhaustion or overload.

D. Pay as you go: While pay as you go is a pricing model rather than a service or feature, it can support the principle of designing for failure by enabling you to scale resources up or down as needed. By paying only for the resources you use, you can avoid over-provisioning and reduce the risk of failures due to insufficient resources.

In conclusion, the three AWS services/features that can assist in supporting the principle of "design for failure and nothing will fail" are Availability Zones, Regions, and Elastic Load Balancer.