Interview Q&A / System Design
System Design interview questions
Caching, scaling, databases and classic design problems for beginners.
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- What does a load balancer do, and what is the difference between L4 and L7 load balancing?
A load balancer sits in front of a group of servers and spreads incoming requests across the healthy ones, so no single server is overloaded and failures are hidden from users. An L4 balancer routes by IP address and port without reading the request. An L7 balancer reads HTTP details such as path, host and headers and can route on them.
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