Can you please look at the jobtracker and tasktracker logs on nodes where the task has been launched ? Also see if the job logs are picking up anything. They'll probably give you clues on what is happening.
Also, is HDFS ok ? i.e. are you able to read files already loaded etc. Thanks hemanth On 9/19/12, Li Shengmei <lisheng...@ict.ac.cn> wrote: > Hi,all > > I revise the source codes of hadoop-1.0.3 and use ant to recompile > hadoop. It compiles successfully. Then I "jar cvf hadoop-core-1.0.3.jar *" > and copy the new hadoop-core-1.0.3.jar to overwirite the $HADOOP_HOME/ > hadoop-core-1.0.3.jar in every node machine. Then I use hadoop to test the > wordcount application. But the application halts at map 0% reduce 0%. > > Does anyone give suggestions? > > Thanks a lot. > > > > May > > > > > > > >