Load Balancer Realistic Use Cases — Distributed System Design

A load balancer is a network device or software that facilitates load balancing — methodically and efficiently distributing network traffic over multiple backend servers in a server pool.

“Use Case” represents a vital feature of load balancers

𝟭. 𝗙𝗮𝗶𝗹𝘂𝗿𝗲 𝗛𝗮𝗻𝗱𝗹𝗶𝗻𝗴
Auto-rerouting away from failed components for high availability and minimal downtime

Fig — Failure Handling

𝟮. 𝗜𝗻𝘀𝘁𝗮𝗻𝗰𝗲 𝗛𝗲𝗮𝗹𝘁𝗵 𝗖𝗵𝗲𝗰𝗸𝘀
Regularly monitors and verifies the instance's health, ensuring incoming traffic solely to operational, healthy instances

Fig — Instance Health Checks

𝟯. 𝗣𝗹𝗮𝘁𝗳𝗼𝗿𝗺 𝗦𝗽𝗲𝗰𝗶𝗳𝗶𝗰 𝗥𝗼𝘂𝘁𝗶𝗻𝗴
Directs platform-specific (mobile, desktop, etc.) requests to separate backend servers for tailored responses

Fig — Platform specific routing