Question

You manage a Ruby on Rails application that lives on a cluster of EC2 instances. Your website occasionally experiences brief, strong, and entirely unpredictable spikes in traffic that overwhelm your EC2 instances' resources and freeze the application. As a result, you're losing recently submitted requests from end users. You use Auto Scaling to deploy additional resources to handle the load during spikes, but the new instances don't spin-up fast enough to prevent the existing application servers from freezing. Which of the following will provide the most cost-effective solution in preventing the loss of recently submitted requests?
A. Keep a large EC2 instance on standby.
B. Increase the size of your existing EC2 instances.
C. Ask AWS support to pre-warm the Elastic Load Balancer.
D. Use Amazon SQS to decouple the application components and keep the requests in queue until the extra Auto-Scaling instances are available."

Answer 1

Answer:

Option D Use Amazon SQS to decouple the application components and keep the requests in queue until the extra Auto-Scaling instances are available.

Explanation:

Amazon SQS is a service that user to decouple the application components and keep the request in queue. This is useful to ensure the distribution of message can be done more reliably and without losing the message. Amazon SQS increase the system fault tolerance. Multiple duplicated copies of the message will be stored across several availability zones to ensure the message are always available whenever it is needed.