Your question is High-Load Log System. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Multiple servers receive logs of which (ip, port) is calling with what packets; design data structures to answer queries such as which IP is highest and which server handles the most load.
Asked in the round 2 stage. Explain how records are ingested, aggregated across servers, and queried efficiently. Discuss how you would detect changing traffic patterns or anomalies without allowing approximate analytics to hide important network events.