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System Design Quiz Practice
Active Recall Drill Session
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Question 1 of 1
medium
System Design
A production real-time chat feature only works reliably in local development (single process) but intermittently fails to deliver messages in production (multiple instances). What's the most likely root cause?
A
A bug in the WebSocket protocol itself
B
The delivery logic checks only the local server's connection table with no cross-server pub/sub mechanism, so delivery only works when sender and recipient happen to land on the same instance
C
The load balancer is fundamentally incompatible with WebSockets
D
The client's browser is outdated
Check Answer