AWS Elastic Load Balancing (ELB)
AWS Elastic Load Balancing automatically distributes incoming application traffic across multiple servers. Think of it as a traffic controller that ensures no single server gets overwhelmed by directing visitors to the least busy server.
Overview
Elastic Load Balancing is a service that acts as the front door to your applications, receiving all incoming traffic and intelligently distributing it across multiple servers (like EC2 instances). This distribution of traffic helps ensure that no single server becomes overloaded while others sit idle.
The service continuously monitors the health of all servers it sends traffic to. If it detects that a server is having problems, it automatically stops sending traffic to that server until it's healthy again. This helps maintain your application's availability even if some servers fail.
ELB can automatically add or remove servers from its distribution list as you scale your application up or down. This makes it work perfectly with services like amazon_ec2_auto_scaling:Amazon EC2 Auto Scaling, allowing your application to handle varying amounts of traffic efficiently.
AWS offers different types of load balancers optimized for different use cases, from simple web applications to complex microservices architectures. The service also handles encryption and decryption of traffic, helping secure your applications.
Example uses
Web Applications: Distribute visitor traffic across multiple web servers to handle high volumes of requests.
Mobile Apps: Balance API requests from mobile applications across backend servers.
Fault Tolerance: Keep applications available by automatically routing traffic away from failed servers.
SSL/TLS Termination: Handle HTTPS encryption/decryption at the load balancer level instead of on individual servers.
Integration with other AWS services
ELB works seamlessly with many AWS services:
- Amazon EC2: Distribute traffic across multiple EC2 instances
- Amazon EC2 Auto Scaling: Automatically adjust the number of servers based on traffic
- Amazon CloudWatch: Monitor traffic patterns and load balancer performance
- AWS Certificate Manager: Manage SSL/TLS certificates for secure connections
Think of Elastic Load Balancing as a smart traffic controller that ensures your application remains fast and available by efficiently directing user requests across your servers.