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Components of a load balancer

  1 min read

At it’s most basic, load balancing is made up of three components:

  • Origin pools: Which contain one or more servers.
  • Origin servers: Which respond to individual requests.
  • A load balancer: Which decides which traffic goes to each origin pool.

​​ How it works

Normally, requests to your application would go to individual servers directly.

With a load balancer, requests first go through the load balancer. Your load balancer then routes requests to specific pools.

Load balancing flowLoad balancing involves a load balancer, pools, origins, monitors, and health monitors.
Request 1
Request 2
Request 3
Pool 3
Origin 5
Origin 6
Pool 2
Origin 3
Origin 4
Pool 1
Origin 1
Origin 2
Request 1
Load balancer
Request 2
Request 3

Within each pool, requests then go to individual servers. And that server is what responds to the request.

Pool traffic flowWhen an incoming request reaches a pool, it then goes to a server within the pool.
Origin pool
Routed by pool
Origin 1
Origin 2
Request 1

This progression of load balancer –> pool –> server is the core part of how a load balancer works.