What does Auto Scaling do?

Auto Scaling is a feature that automatically adjusts the number of EC2 instances in a given environment based on the current demand. This process enables applications to maintain performance and availability by scaling out (adding instances) during periods of high demand and scaling in (removing instances) when demand decreases. By doing so, Auto Scaling helps optimize costs, as you are only using the resources necessary to handle the workload at any given time.

The benefit of this capability is particularly significant for applications with variable workloads, ensuring that they remain resilient and responsive without incurring unnecessary expenses. As traffic increases and workloads surge, Auto Scaling can launch new instances based on predefined scaling policies or metrics, such as CPU utilization or network traffic. Conversely, as workloads decrease, it can terminate instances, thereby right-sizing your infrastructure.

This automatic adjustment is crucial for maintaining the performance of applications while also managing costs effectively, making it a vital component of an elastic cloud architecture.