At the top of the job tracker in Hadoop, it reports blacklisted, greylisted, and excluded nodes.
Hadoop docs say nodes can be blacklisted by a monitoring script. It does not say if there is a default monitoring script, or what it might do. mapr says a task tracker is blacklisted if a node is blacklisted by mapred.max.tracker.blacklists jobs. (It says a task tracker is blacklisted from a job if it is blacklisted mapred.max.tracker.failures times in a job.)
So which is it: monitoring script; this blacklist-per-job, then across jobs; both; some other mechanism? Is there a definitive source of this information?
What about greylisting? What about excluded?
Please rigorously define blacklisting, greylisting, excluded nodes, preferably with a ref. Thanks!