Where does hadoop mapreduce framework send my System.out.print() statements ? (stdout)

jason picture jason · Jul 8, 2010 · Viewed 65.3k times · Source

I want to debug a mapreduce script, and without going into much trouble tried to put some print statements in my program. But I cant seem to find them in any of the logs.

Answer

rOrlig picture rOrlig · Apr 26, 2011

Actually stdout only shows the System.out.println() of the non-map reduce classes.

The System.out.println() for map and reduce phases can be seen in the logs. Easy way to access the logs is

http://localhost:50030/jobtracker.jsp->click on the completed job->click on map or reduce task->click on tasknumber->task logs->stdout logs.

Hope this helps