Horizontal Scaling

Horizontal scaling adds more server instances to share load, enabling near-linear capacity growth and built-in redundancy.

Diagram

  Before:  [Server 1] ── handles 1000 req/s (maxed out)
  
  After:   [Server 1] ──┐
           [Server 2] ──┼──▶ Load Balancer ──▶ 2000 req/s total
           [Server 3] ──┘

In Depth

Horizontal scaling (scaling out) means adding more machines or container instances to your system rather than upgrading a single machine. Each new instance shares the incoming traffic.

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