Shulou(Shulou.com)06/03 Report--

1. Show the current directory structure

# display the current directory structure hadoop fs-ls # Recursively display the current directory structure hadoop fs-ls-R # display the contents of the root directory hadoop fs-ls /

two。 Create a directory

# create directory hadoop fs-mkdir # Recursive create directory hadoop fs-mkdir-p

3. Delete operation

# delete file hadoop fs-rm # Recursive delete directory and file hadoop fs-rm-R

4. Load files locally to HDFS

# choose one of the two to execute hadoop fs-put [localsrc] [dst] hadoop fs-copyFromLocal [localsrc] [dst]

5. Export files from HDFS to local

# choose one of the two to execute hadoop fs-get [dst] [localsrc] hadoop fs-copyToLocal [dst] [localsrc]

6. View the contents of the file

# just choose one of the two to execute hadoop fs-text hadoop fs-cat

7. Show the last thousand bytes of the file

Hadoop fs-tail #, as under Linux, continuously listens for changes in the contents of the file and displays the last kilobyte of the file hadoop fs-tail-f

8. Copy a file

Hadoop fs-cp [src] [dst]

9. Move Fil

Hadoop fs-mv [src] [dst]

10. Count the file size under the current directory

Default unit byte-s: displays the sum of all file sizes,-h: will display the file size in a more friendly way (for example, 64.0m instead of 67108864) hadoop fs-du

11. Merge and download multiple files

-nl adds a newline character (LF) at the end of each file-skip-empty-file skips the empty file hadoop fs-getmerge# example the hbase-policy.xml and hbase-site.xml files on HDFS are merged and downloaded to the local / usr/test.xmlhadoop fs-getmerge-nl / test/hbase-policy.xml / test/hbase-site.xml / usr/test.xml

twelve。 Statistics of the free space information of the file system

Hadoop fs-df-h /

13. Change the file replication factor

Hadoop fs-setrep [- R] [- w] changes the replication factor of the file. If path is a directory, change the replication factor of all files under it-w: request command whether to wait for replication to complete # example hadoop fs-setrep-w 3 / user/hadoop/dir1

14. Authority control

# permission control is the same as on Linux. # change the group to which the file or directory belongs. The user must be the owner or superuser of the file. Hadoop fs-chgrp [- R] GROUP URI [URI.] # the access user to modify a file or directory must be the owner or superuser of the file. Hadoop fs-chmod [- R] URI [URI.] # the owner of the modification file must be a superuser. Hadoop fs-chown [- R] [OWNER] [: [GROUP]] URI [URI]

15. File detection

Hadoop fs-test-[defsz] URI

Optional options:

-d: returns 0 if the path is a directory. -e: returns 0 if the path exists. -f: returns 0 if the path is a file. -s: returns 0 if the path is not empty. -r: returns 0 if the path exists and read permission is granted. -w: returns 0 if the path exists and write permission is granted. -z: returns 0 if the file length is zero. # example hadoop fs-test-e filename

For more articles in big data's series, please see the GitHub Open Source Project: big data's getting started Guide.

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