SYSTEM-DESIGN
    intermediate

    Load Balancer

    Software Engineer path · lesson 69 of 99
    Total Requests: 1
    Active: 1
    Load Distribution: 0-0-0
    Next: Server B
    Incoming Requests
    1 total
    Load Balancer
    round robin
    REQ
    R1
    Server A
    Active: 1Total: 0
    Server B
    Active: 0Total: 0
    Server C
    Active: 0Total: 0
    Live Algorithm Analysis

    Round Robin: Request 1 routed to Server A (next in sequence)

    Round Robin: Requests distributed sequentially across servers. Simple but ignores server load and capacity.

    Pick the strategy

    Sort

    Sort each description into the load-balancing strategy it describes.

    Tap a piece, then tap where it goes — or drag it. Tap the tray to take one back.

    Round robin

    Drop items here

    Least connections

    Drop items here

    Weighted

    Drop items here
    6 pieces left to place

    Test your knowledge

    21 questions
    Question 1 of 21
    Score: 0

    Which load balancing algorithm routes traffic to the server with the fewest active connections?

    The short version

    Think of a load balancer like a restaurant host who seats guests at different tables to ensure no single waiter is overwhelmed.

    In more depth

    Load Balancing

    A load balancer distributes network traffic across multiple servers to ensure no single server bears too much demand.

    Algorithms

    Round Robin: Requests are distributed sequentially
    Least Connections: Routes to the server with fewest active connections
    Weighted: Servers with higher capacity get more traffic

    Key Concepts

    Health checks ensure failed servers are removed from the pool
    Session persistence (sticky sessions) for stateful applications
    Layer 4 vs Layer 7 load balancing

    Interview Questions

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