how to get system.out.println() work in hadoop

2014-07-11T05:14:13

I am trying to debug in hadoop. I want to print some variables out to terminal with System.out.println(), but nothing has been output to the terminal. I checked the jobhistory/logs under

http://serverurl:19888/jobhistory/app

but still only INFOs there, no println()s. Furthermore, I have modified log4j.properties, changed

hadoop.root.logger=INFO,console

to

hadoop.root.logger=ALL,console

but still not working.

Anyone has some ideas? Thank you very much.

Copyright License:
Author:「Robert」,Reproduced under the CC 4.0 BY-SA copyright license with link to original source & disclaimer.
Link to:https://stackoverflow.com/questions/24686414/how-to-get-system-out-println-work-in-hadoop

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Copyright License:Reproduced under the CC 4.0 BY-SA copyright license with link to original source & disclaimer.