Command Line in HDFS and HDFS command line
Command Line in HDFS
This article describes the functions and usage of several common command lines when running HDFS with command lines ~
1. fs
Fs is the command line action to start. It is used to provide a series of sub-commands.
Format: hadoop fs-cmd <args>
Cmd is a sub-command, and args is a specific command operation.
For example, hadoop fs-help
Or fs is the father of other sub-commands, and the rest are in the "-cmd" mode!
2.-cat output
Hadoop fs-cat URI
Output the file specified by the path to the screen
3.-copyFromLocal: copy the local file to HDFS.
Hadoop fs-copyFromLocal <localsrc> URI
Hadoop fs-copyFromLocal/usr/localFile.txt sample.txt
Local files can be uploaded to HDFS, and the target path is simplified.
4.-cp Replication
Hadoop fs-cp/usr/file1/usr/files/user/dir
Copy the files in the Source Path to the target path. There can be multiple source paths, but only one target path can exist.
5.-du: displays the size of all files in the directory, or the size of a file.
Hadoop fs-du/usr/dir1
6.-dus: displays the file size.
7.-expunge clear the recycle bin
Hadoop fs-expunge
8.-get copy the local file to the local system
Usage: hadoop fs-get <locaodst>
Hadoop fs-get/usr/file localfile
9.-put copy the local file to the target file system
Usage: hadoop fs-put <localsrc> <dst>
Hadoop fs-put localfile hadfs: // host: port/usr/file
10.-ls browse local files
Usage: hadoop fs-ls <arg>
Returned information:
File name <Number of replicas> file size modification date permission user ID/group ID
11.-The lsr recursively queries the File Content
12.-create the corresponding file directory in mkdir
Hadoop fs-mkdir/usr/dir1/dir2/dir3/file
13.-mv mobile
Move the source file to the target path. The target path can contain multiple
Hadoop fs-mv/usr/file1/usr/file2
14.-rm Deletion
Hadoop fs-rm URI
15.-rmr recursive Deletion
16.-Setrep: change the number of copies
Hadoop fs-setrep-w 3-R/usr/file
17.-Test check the file
Use ezd to check the file
-E: Check whether the file exists. If yes, 0 is returned;
-Z: Check whether the file is 0 bytes. If yes, 0 is returned;
-D: Check whether the path is a directory. If yes, 1 is returned;
18.-text: output the source file to the text format
The format of hadoop fs-text <src> is zip and Text.