High Availability, Fault Tolerance, and Auto Scaling Flashcards

Which AWS Auto Scaling policy adjusts capacity based on a target value for a specific metric, such as 70% CPU utilization?

Answer: Target Tracking Scaling

Target Tracking Scaling automatically adjusts the number of instances to keep a chosen metric, like CPU utilization, at or near a specified target value.

What is the purpose of an EC2 Auto Scaling lifecycle hook?

Answer: To pause instance launch or termination so custom actions can be performed

Lifecycle hooks put instances in a wait state during launch or termination, allowing time to run scripts, drain connections, or register/deregister from services.

Which AWS service provides managed service discovery for microservices running on ECS or EC2?

Answer: AWS Cloud Map

AWS Cloud Map allows you to register application resources and define custom names, enabling services to discover each other dynamically.

Which ELB type is optimized for handling millions of requests per second with ultra-low latency at the TCP layer?

Answer: Network Load Balancer

Network Load Balancer operates at Layer 4 and is designed for extreme performance, handling millions of requests per second with very low latency.

What does an EC2 Auto Scaling warm pool enable?

Answer: Pre-initialized instances that can be quickly launched to handle demand spikes

A warm pool maintains a pool of pre-initialized EC2 instances that have completed their bootstrap process, enabling faster scale-out response times.

Which Route 53 routing policy distributes traffic based on the geographic location of DNS queries?

Answer: Geolocation routing

Geolocation routing in Route 53 routes traffic to resources based on the geographic location of the user, enabling region-specific content serving.