Load Balancers

Networking

Load balancers refers to efficiently distributing incoming network traffic across a group of backend servers.This is used basically to increase capacity and reliability of applications. It improves the overall performance of the applications by reducing the burden on servers which are mainly associated with managing and maintaining network sessions,as well as by performing application-specific tasks.

Load Balancing Algorithms

Different load balancing algorithms

• Round Robin — Requests are distributed across the group of servers sequentially.
• Least Connections — A new request is sent to the server with the fewest current connections to clients. The relative computing capacity of each server is factored into determining which one has the least connections.
• Least Time — Sends requests to the server selected by a formula that combines the
  fastest response time and fewest active connections. Exclusive to NGINX Plus.
• Hash — Distributes requests based on a key you define, such as the client IP address or
  the request URL. NGINX Plus can optionally apply a consistent hash to minimize redistribution
  of loads if the set of upstream servers changes.
• IP Hash — The IP address of the client is used to determine which server receives the request.
• Random with Two Choices — Picks two servers at random and sends the request to the server.

Benefits of Load Balancing

1. Performance and Speed : Slow loading websites are red flags to a customer. Everyone wants no delay in the website.
2. Monitoring Application health : It provides detailed performance metrics ,error alerts and reporting ,adjust and optimize its infrastructure.
3. Managing Failures: A load balancer will detect a server failure early and route traffic to healthy servers still in operation.The result is that failures cause minimal to no disruption in operation.

The type of load balancer that’s right for you will depend on your systems and your objectives. Correct selection is important to ensure that you get the right optimization without going beyond what you need.