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The FileSystem (FS) shell is invoked by bin/hadoop fs <args>. All the FS shell commands take path URIs as arguments. The URI format is scheme://autority/path. For HDFS the scheme is hdfs, and for the local filesystem the scheme is file. The scheme and authority are optional. If not specified, the default scheme specified in the configuration is used. An HDFS file or directory such as /parent/child can be specified ashdfs://namenodehost/parent/child or simply as /parent/child (given that your configuration is set to point tohdfs://namenodehost). Most of the commands in FS shell behave like corresponding Unix commands. Differences are described with each of the commands. Error information is sent to stderr and the output is sent tostdout.
Usage: hadoop fs -cat URI [URI …]
Copies source paths to stdout.
Example:
Exit Code:
Returns 0 on success and -1 on error.Usage: hadoop fs -chgrp [-R] GROUP URI [URI …]
Change group association of files. With -R, make the change recursively through the directory structure. The user must be the owner of files, or else a super-user. Additional information is in the .
Usage: hadoop fs -chmod [-R] <MODE[,MODE]... | OCTALMODE> URI [URI …]
Change the permissions of files. With -R, make the change recursively through the directory structure. The user must be the owner of the file, or else a super-user. Additional information is in the .
Usage: hadoop fs -chown [-R] [OWNER][:[GROUP]] URI [URI ]
Change the owner of files. With -R, make the change recursively through the directory structure. The user must be a super-user. Additional information is in the .
Usage: hadoop fs -copyFromLocal <localsrc> URI
Similar to command, except that the source is restricted to a local file reference.
Usage: hadoop fs -copyToLocal [-ignorecrc] [-crc] URI <localdst>
Similar to command, except that the destination is restricted to a local file reference.
Usage: hadoop fs -cp URI [URI …] <dest>
Copy files from source to destination. This command allows multiple sources as well in which case the destination must be a directory.
Example:Exit Code:
Returns 0 on success and -1 on error.
Usage: hadoop fs -du URI [URI …]
Displays aggregate length of files contained in the directory or the length of a file in case its just a file.
Example: hadoop fs -du /user/hadoop/dir1 /user/hadoop/file1 hdfs://nn.example.com/user/hadoop/dir1 Exit Code: Returns 0 on success and -1 on error.Usage: hadoop fs -dus <args>
Displays a summary of file lengths.
Usage: hadoop fs -expunge
Empty the Trash. Refer to for more information on Trash feature.
Usage: hadoop fs -get [-ignorecrc] [-crc] <src> <localdst>
Copy files to the local file system. Files that fail the CRC check may be copied with the -ignorecrc option. Files and CRCs may be copied using the -crc option.
Example:
Exit Code:
Returns 0 on success and -1 on error.
Usage: hadoop fs -getmerge <src> <localdst> [addnl]
Takes a source directory and a destination file as input and concatenates files in src into the destination local file. Optionally addnl can be set to enable adding a newline character at the end of each file.
Usage: hadoop fs -ls <args>
For a file returns stat on the file with the following format:
filename <number of replicas> filesize modification_date modification_time permissions userid groupid For a directory it returns list of its direct children as in unix. A directory is listed as: dirname <dir> modification_time modification_time permissions userid groupid Example: hadoop fs -ls /user/hadoop/file1 /user/hadoop/file2 hdfs://nn.example.com/user/hadoop/dir1 /nonexistentfile Exit Code: Returns 0 on success and -1 on error.Usage: hadoop fs -lsr <args>
Recursive version of ls. Similar to Unix ls -R.Usage: hadoop fs -mkdir <paths>
Takes path uri's as argument and creates directories. The behavior is much like unix mkdir -p creating parent directories along the path.
Example:
Exit Code:
Returns 0 on success and -1 on error.
Usage: dfs -moveFromLocal <src> <dst>
Displays a "not implemented" message.
Usage: hadoop fs -mv URI [URI …] <dest>
Moves files from source to destination. This command allows multiple sources as well in which case the destination needs to be a directory. Moving files across filesystems is not permitted.
Example:Exit Code:
Returns 0 on success and -1 on error.
Usage: hadoop fs -put <localsrc> ... <dst>
Copy single src, or multiple srcs from local file system to the destination filesystem. Also reads input from stdin and writes to destination filesystem.
Exit Code:
Returns 0 on success and -1 on error.
Usage: hadoop fs -rm URI [URI …]
Delete files specified as args. Only deletes non empty directory and files. Refer to rmr for recursive deletes.
Example:Exit Code:
Returns 0 on success and -1 on error.
Usage: hadoop fs -rmr URI [URI …]
Recursive version of delete.
Example:Exit Code:
Returns 0 on success and -1 on error.
Usage: hadoop fs -setrep [-R] <path>
Changes the replication factor of a file. -R option is for recursively increasing the replication factor of files within a directory.
Example:
Exit Code:
Returns 0 on success and -1 on error.
Usage: hadoop fs -stat URI [URI …]
Returns the stat information on the path.
Example:
Exit Code:
Returns 0 on success and -1 on error.Usage: hadoop fs -tail [-f] URI
Displays last kilobyte of the file to stdout. -f option can be used as in Unix.
Example:
Exit Code:
Returns 0 on success and -1 on error.Usage: hadoop fs -test -[ezd] URI
Options:
-e check to see if the file exists. Return 0 if true. -z check to see if the file is zero length. Return 0 if true -d check return 1 if the path is directory else return 0.Example:
Usage: hadoop fs -text <src>
Takes a source file and outputs the file in text format. The allowed formats are zip and TextRecordInputStream.
Usage: hadoop fs -touchz URI [URI …]
Create a file of zero length.
Example:
Exit Code:
Returns 0 on success and -1 on error.
From http://blog.csdn.net/thundertide/article/details/7621493