[hadoop@hadoop001 bin]$ hadoop jar /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/share/hadoop/mapreduce/hadoop-mapreduce-examples-2.6.0-cdh5.7.0.jar wordcount /input/wc/hello.txt /output/wc/
/home/hadoop/app/hadoop-2.6.0-cdh5.7.0/etc/hadoop/hadoop-env.sh: line 2: or: command not found
19/03/19 23:35:04 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform… using builtin-java classes where applicable
19/03/19 23:35:05 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
19/03/19 23:35:05 WARN security.UserGroupInformation: PriviledgedActionException as:hadoop (auth:SIMPLE) cause:org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory hdfs://hadoop001:8020/output/wc already exists
org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory hdfs://hadoop001:8020/output/wc already exists
at org.apache.hadoop.mapreduce.lib.output.FileOutputFormat.checkOutputSpecs(FileOutputFormat.java:146)
at org.apache.hadoop.mapreduce.JobSubmitter.checkSpecs(JobSubmitter.java:270)
at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:143)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1307)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1304)