What happens when a data node fails? › Category: Hadoop › What happens when a data node fails? 0 Vote Up Vote Down Editor">Editor Staff asked 2 years ago What happens when a data node fails? 1 Answers 0 Vote Up Vote Down Editor">Editor Staff answered 2 years ago If a data node fails the job tracker and name node will detect the failure. After that, all tasks are re-scheduled on the failed node and then name node will replicate the user data to another node.