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Explain what is JobTracker in Hadoop? What are the actions followed by Hadoop?

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Explain what is JobTracker in Hadoop? What are the actions followed by Hadoop?
posted Nov 18, 2014 by Amit Kumar Pandey

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In Hadoop for submitting and tracking MapReduce jobs, JobTracker is used. Job tracker run on its own JVM process

Hadoop performs following actions in Hadoop:

  1. Client application submit jobs to the job tracker
  2. JobTracker communicates to the Namemode to determine data location
  3. Near the data or with available slots JobTracker locates TaskTracker nodes
  4. On chosen TaskTracker Nodes, it submits the work
  5. When a task fails, Job tracker notify and decides what to do then.
  6. The TaskTracker nodes are monitored by JobTracker
answer Dec 2, 2014 by Kali Mishra
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