HDFS Commands

* HDFS Commnads

  Running file system commands in HDFS:

  hdfs dfs -du  <hdfs_path>
  hdfs dfs -ls -R   <hdfs_path>  : To list all files in the HDFS path
      you can also use wildcard for pattenmatching. like
      hdfs dfs -ls  dir1/dir2*/file1

  hdfs dfs -rm -R   <hdfs_path> : To remove all files under the hdfs path
     hdfs dfs -rm -R -skipTrash  dir1/dir2*/file1  ( wildcard)

  hdfs dfs is same as now deprecated "hadoop dfs".  "hdfs dfs"  works only for HDFS , while "hadoop fs .." works all kinds of file systems.


* To temporarily enable Kerberos  authentication for a user
kinit -k -t  /home/username/username.keytab  username@doamin

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