Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 424 discussion

Has to be A, It can scale down if required and you will be charged for what you use with fargate. Secondly they have not said the backend can have timeouts or can be down for a little period of time or something. So it has to rule out any spot instances even though they are cheaper.

Reserved+ spot . Fargate for serverless

I think in A it should be Fargat spot, B means standard spot. The former uses auto scaling and the later does not

The requirement is to have an autoscaling , and fargate can do that. Spot instance only works when the work load is fault tolerant. Furthermore it is told to use on-demand instance.

I will go with A. Where does the question mentions that the workload interruptions are accepted.

B) because firegate is containser

so what ive make up from this scenario is: the key word right here is "backend nodes" you cant use a serverless compute service with nodes and you need to use EC2s so if we had ECS EC2 lunch type or on-demand EC2s as an options for the backend, they would be true?

24-7 usage for fe -> reserved instance irregular workload for be -> spot instance

Not A because Fargate runs containers, not EC2 instances. But we have no indication that the workload would be containerized; it runs "on EC2 instances". Not C and D because frontend must run 24/7, can't use Spot. Thus B, yes, Spot instances are risky, but as they need to run "only for a short time" it seems acceptable. Technically ideal option would be Reserved Instances for frontend nodes and On-demand instances for backend nodes, but that is not an option here.

Not sure the application can be containerized

it is safe

Reserved Instances (RIs) for Frontend Nodes: Since the frontend nodes need to run continuously (24/7), using Reserved Instances for them makes sense. RIs provide significant cost savings compared to On-Demand Instances for steady-state workloads. Spot Instances for Backend Nodes: Spot Instances are suitable for short-duration workloads and can be significantly cheaper than On-Demand Instances. Since the number of backend nodes varies during the day, Spot Instances can help you take advantage of spare capacity at a lower cost. Keep in mind that Spot Instances may be interrupted if the capacity is needed elsewhere, so they are best suited for stateless and fault-tolerant workloads.

AWS Fargate is a serverless compute engine for containers that allows you to run containers without having to manage the underlying infrastructure. It simplifies the process of deploying and managing containerized applications by abstracting away the complexities of server management, scaling, and cluster orchestration. No containerized application requirements are mentioned in the question. Plain EC2 instances. So Fargate is not actually an option

A is fargate, which is none sense. B seems more OK (though none-sense)

Fargate for backend node

(B) would take chance, though unlikely (A) is server-less auto-scaling. In case backend is idle, it might scale down, save money but no need to worry for interruption by Spot instance.

If you will use spot instances you must assumme lost any job in course. This scenary has not explicit mentions about aaplication can tolerate this situations, then, on my opinion, option A is the most suitable.