在redhat enterpriser linux6上用eclipse运行hadoop 自带的WordCount程序，报错如下，小弟初学，求大神指教

[l_shua]

15/03/16 18:56:59 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
15/03/16 18:56:59 WARN mapred.JobClient: No job jar file set. User classes may not be found. See JobConf(Class) or JobConf#setJar(String).
15/03/16 18:56:59 INFO mapred.JobClient: Cleaning up the staging area file:/tmp/hadoop-root/mapred/staging/root760300295/.staging/job_local760300295_0001
15/03/16 18:56:59 ERROR security.UserGroupInformation: PriviledgedActionException as:root cause:org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory /root/hadoop/output already exists
Exception in thread "main" org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory /root/hadoop/output already exists
at org.apache.hadoop.mapreduce.lib.output.FileOutputFormat.checkOutputSpecs(FileOutputFormat.java:137)
at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:973)
at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:936)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1190)
at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:936)
at org.apache.hadoop.mapreduce.Job.submit(Job.java:550)
at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:580)
at com.lshua.WordCount.main(WordCount.java:67)

[zccao_gong]

代码贴上来看看？

[zccao_gong]

Output directory /root/hadoop/output already exists 加强下英文能力问题就解决了！ hdfs的文件删除应该就OK。

[l_shua]

这个我知道。删了还是不行。报的错除了那一行剩下都是

[tchqiq]

这mapreduce是往hdfs上写 咋感觉你是写到了本地的目录上呢？你先看看你能访问你的hdfs上不~

[l_shua]

就是往hdfs上写的。hdfs也可以访问上

[tchqiq]

我估计你是这样~mr只会输出到最后一级目录下，你把output 改成output2 前提是你先新建了output2目录 然后输出到这个目录下就可以了

[搜索与推荐Wiki]

是不是目录问题亚，你好好检查一下你的目录