Scaling Reads easy
You have 5 Read Replicas. How does the application know which one to ask for data?
- A A Load Balancer sits in front of the replicas and distributes the traffic (e.g., Round Robin).
- B The application randomly guesses IPs.
- C The Primary database routes the traffic.
- D The user manually selects a server.
Answer: A. A Load Balancer sits in front of the replicas and distributes the traffic (e.g., Round Robin).
A Load Balancer provides a single entry point (Virtual IP). The app talks to the LB, and the LB picks one of the healthy replicas to handle the request.
One system design question a day, with spaced repetition so the ones you miss come back.
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