Hadoop Basics Tutorial-3rd Chapter HDFS: Distributed File System (3.5 HDFS Basic command) (draft) __hadoop

3rd Chapter HDFS: Distributed File System 3.5 HDFs Basic Command

HDFs Order Official documents:
http://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-hdfs/HDFSCommands.html 3.5.1 Usage

[Root@node1 ~]# HDFs dfs usage:hadoop FS [generic options] [-appendtofile <localsrc> ... <dst>] [-cat
    [-IGNORECRC] <src> ...]
    [-checksum <src> ...]
    [-CHGRP [-R] GROUP PATH ...] [-chmod [-R] <mode[,mode] ... |
    Octalmode> PATH ...]
    [-chown [R] [Owner][:[group]] PATH ...]
    [-copyfromlocal [-f] [-P] [-l] <localsrc> <dst>]
    [-copytolocal [P] [-IGNORECRC] [-CRC] <src> ... <localdst>]
    [-count [-Q] [-h] [-v] [-X] <path> ...]
    [-CP [-f] [P |-p[topax]] <src> ... <dst>]
    [-createsnapshot <snapshotDir> [<snapshotname>]]
    [-deletesnapshot <snapshotDir> <snapshotname>]
    [-DF [-H] [<path>]]
    [-DU [-S] [-h] [-X] <path> ...]
    [-expunge]
    [-find <path> ... <expression> ...]
    [-get [P] [-IGNORECRC] [-CRC] <src> ... <localdst>]
    [-getfacl [R] <path>] [-getfattr [-R] {-N name |-d} [-E en] <paTH&GT] [-getmerge [-NL] <src> <localdst>] [-help [cmd ...]]
    [-ls [-C] [-d] [-h] [-Q] [-r] [-T] [-S] [-r] [-u] [<path>]]
    [-mkdir [P] <path> ...]
    [-movefromlocal <localsrc> ... <dst>]
    [-movetolocal <src> <localdst>]
    [-mv <src> ... <dst>]
    [-put [-f] [-P] [-l] <localsrc> <dst>]
    [-renamesnapshot <snapshotDir> <oldName> <newname>]
    [-RM [F] [-r|-r] [-skiptrash] <src> ...]
    [-rmdir [--ignore-fail-on-non-empty] <dir> ...] [-setfacl [-R] [{-b|-k} {-m|-x <acl_spec>} <path>]|
    [--set <acl_spec> <path>]]
    [-setfattr {-n name [-V value] |-x name} <path>]
    [-setrep [-R] [W] <rep> <path> ...]
    [-STAT [format] <path> ...]
    [-tail [F] <file>]
    [-test-[defsz] <path>]
    [-text [-IGNORECRC] <src> ...]
    [-touchz <path> ...]
[-usage [cmd ...]] Generic optIons supported are-conf <configuration file> Specify an application configuration file-d            ; Use value for given Property-fs <local|namenode:port> specify a NAMENODE-JT <local|resourcemanager:port&gt    ; Specify a resourcemanager-files <comma separated list of files> specify comma separated files to is copied to th E map reduce cluster-libjars <comma separated list of jars> specify Comma separated jar files to include
Classpath. -archives <comma separated list of archives> specify Comma separated archives to is unarchived on the compute mac
Hines. The General Command line syntax is Bin/hadoop command [genericoptions] [commandoptions]

3.5.2 HDFs Dfs-mkdir

THE-P option behavior is much like Unix mkdir-p, creating parent directories along the path.

[Root@node1 ~]# HDFs dfs-mkdir-p input [root@node1 ~]# HDFs dfs-mkdir-p-/ABC

The directory created by HDFs will be placed under the/user/{username}/directory by default, where {username} is the current user name. So the input directory should be under/user/root/.

Create an ABC directory under the HDFs root directory. 3.5.3 HDFs Dfs-ls

[Root@node1 ~]# HDFs dfs-ls/
Found 2 Items
drwxr-xr-x   -root supergroup          0 2017-05-14
09:40/abc drwx R-xr-x   -root supergroup          0 2017-05-14 09:37/user [root@node1 ~]# hdfs dfs-ls/user-
Found 1 Items
Drwxr-xr-x   -root supergroup          0 2017-05-14 09:37/user/root
[root@node1
~]# HDFs-Dfs-ls/user/root Found 1 Items
drwxr-xr-x   -root supergroup          0 2017-05-14 09:37/user/root/input

3.5.4 HDFs dfs-put

Usage:hdfs dfs-put ...
Copy Single-SRC, or multiple srcs from local file system to the destination file system. Also reads input from stdin and writes to destination file system.
HDFs dfs-put localfile/user/hadoop/hadoopfile
HDFs dfs-put localfile1 localfile2/user/hadoop/hadoopdir
HDFs dfs-put localfile hdfs://nn.example.com/hadoop/hadoopfile
HDFs dfs-put-hdfs://nn.example.com/hadoop/ Hadoopfile reads the input from stdin.
Exit Code:
Returns 0 on success and-1 on error.