hi, Nachiket, * I think if you output something to stderr, you should be able to find it in the .out log. * *Just make sure you are checking the right .out log file, * *you can do that by checking which tasktrackers are running you job from the web UI.* * * * * On Tue, Apr 6, 2010 at 6:56 PM, Nachiket Vaidya <nachik...@gmail.com> wrote:
> I have the following doubts: > 1. How to print log information in Hadoop. In the documentation, I have > read > that hadoop-<username>-<processname>-<machinename>.log contains logs. I > have > used > Log log = LogFactory.getLog(FBEMMapper.class); > and > log.info(....); > > for printing into log, but I do not see any log information in log file. I > have also used System.out.println() but these are also not getting printed > in .log or .out file. > Do we need to change some log level in hadoop? > Do we need to enable logging for some class? > which log4j.properties file we need to change? > > Firstly, am I doing right things for logging? > > Actually the problem is I have written my custom FileInputFormat > and WritableComparable for my purpose. My program runs fine, but I do not > see any output. That is why I need to print some log statement to debug the > problem. > > Thank you. > > > - Nachiket >
