Question

Explain job scheduling through JobTracker.

Answer 1

JobTracker is responsible for communicating with NameNode in order to identify or detect the data location and submit the work to the TaskTracker node. The TaskTracker plays a significant role as it will be notifying the JobTracker if there is any job failure. Job scheduling is referred to as the heartbeat reporter which involves the reassuring of the JobTracker stating that it is still alive. Later, the JobTracker is responsible for the actions present in it and it also provides the flexibility to either resubmit the job or mark a specific record as unreliable or blacklist it.

Answer 2

JobTracker communicates with NameNode to identify data location and submits the work to TaskTracker node. The TaskTracker plays a major role as it notifies the JobTracker for any job failure. It actually is referred to the heartbeat reporter reassuring the JobTracker that it is still alive. Later, the JobTracker is responsible for the actions as in it may either resubmit the job or mark a specific record as unreliable or blacklist it.