AWS Elastic Load Balancing
AWS Elastic Load Balancing (ELB) is a managed load balancing service that automatically distributes incoming application traffic across multiple targets, such as Amazon EC2 instances, containers, and IP addresses, within one or more Availability Zones. It monitors the health of its registered targets and routes traffic only to healthy targets, ensuring high availability and fault tolerance for applications. ELB supports three types of load balancers: Application Load Balancer (ALB), Network Load Balancer (NLB), and Classic Load Balancer (CLB), each optimized for different use cases.
Developers should use AWS Elastic Load Balancing when building scalable, highly available applications on AWS to handle varying traffic loads and improve reliability by distributing requests across multiple resources. It is essential for web applications, microservices architectures, and real-time streaming workloads, as it helps prevent downtime and performance bottlenecks by automatically scaling and rerouting traffic based on health checks. For example, an e-commerce site during a flash sale can use ELB to manage sudden traffic spikes without manual intervention.