AWS Certified Cloud Practitioner (CLF-C02)Cloud Technology and ServicesMedium
A company is hosting a web application on AWS and wants to ensure high availability and fault tolerance. They have deployed their application across multiple EC2 instances. To distribute incoming traffic evenly across these instances and automatically route around unhealthy ones, which service should they use?
- AElastic Load Balancing (ELB)
- BAWS Global Accelerator
- CAmazon CloudFront
- DAmazon Route 53
Show answer & explanationAnswer & explanation
Correct answer: A. Elastic Load Balancing (ELB)
Elastic Load Balancing (ELB) automatically distributes incoming application traffic across multiple targets, such as EC2 instances, in multiple Availability Zones. It also monitors the health of its registered targets and routes traffic only to healthy instances.
Why the other options are wrong
- B. AWS Global Accelerator improves availability and performance by directing traffic to optimal endpoints globally, but it operates at a higher level than distributing traffic across instances within a region.
- C. Amazon CloudFront is a Content Delivery Network (CDN) for caching and delivering static and dynamic web content, not for distributing application traffic across backend EC2 instances.
- D. Amazon Route 53 is a DNS service that can direct traffic at the DNS level, but it doesn't distribute traffic within a set of instances or perform health checks at the application level.
Elastic Load Balancing (ELB)
Automatically distributes incoming application traffic across multiple targets, such as EC2 instances, in multiple Availability Zones.
- Distributes traffic across multiple targets
- Performs health checks on targets
- Enhances fault tolerance and high availability
- Supports Application, Network, and Gateway Load Balancers
Memory trick: ELB: traffic flows, health it knows, faults it bypasses, as the workload grows.