hadoop学习之HDFS命令行操作

[root@hadoop000 ~]# hadoop fs
Usage: hadoop fs [generic options]
        [-appendToFile  ... ]
        [-cat [-ignoreCrc]  ...]
        [-checksum  ...]
        [-chgrp [-R] GROUP PATH...]
        [-chmod [-R] [,MODE]... | OCTALMODE> PATH...]
        [-chown [-R] [OWNER][:[GROUP]] PATH...]
        [-copyFromLocal [-f] [-p] [-l]  ... ]
        [-copyToLocal [-p] [-ignoreCrc] [-crc]  ... ]
        [-count [-q] [-h] [-v] [-x]  ...]
        [-cp [-f] [-p | -p[topax]]  ... ]
        [-createSnapshot  []]
        [-deleteSnapshot  ]
        [-df [-h] [ ...]]
        [-du [-s] [-h] [-x]  ...]
        [-expunge]
        [-find  ...  ...]
        [-get [-p] [-ignoreCrc] [-crc]  ... ]
        [-getfacl [-R] ]
        [-getfattr [-R] {-n name | -d} [-e en] ]
        [-getmerge [-nl]  ]
        [-help [cmd ...]]
        [-ls [-C] [-d] [-h] [-q] [-R] [-t] [-S] [-r] [-u] [ ...]]
        [-mkdir [-p]  ...]
        [-moveFromLocal  ... ]
        [-moveToLocal  ]
        [-mv  ... ]
        [-put [-f] [-p] [-l]  ... ]
        [-renameSnapshot   ]
        [-rm [-f] [-r|-R] [-skipTrash]  ...]
        [-rmdir [--ignore-fail-on-non-empty] <dir> ...]
        [-setfacl [-R] [{-b|-k} {-m|-x } ]|[--set  ]]
        [-setfattr {-n name [-v value] | -x name} ]
        [-setrep [-R] [-w]   ...]
        [-stat [format]  ...]
        [-tail [-f] ]
        [-test -[defsz] ]
        [-text [-ignoreCrc]  ...]
        [-touchz  ...]
        [-usage [cmd ...]]

Generic options supported are
-conf      specify an application configuration file
-D             use value for given property
-fs |namenode:port>      specify a namenode
-jt |resourcemanager:port>    specify a ResourceManager
-files     specify comma separated files to be copied to the map reduce cluster
-libjars     specify comma separated jar files to include in the classpath.
-archives     specify comma separated archives to be unarchived on the compute machines.

The general command line syntax is
bin/hadoop command [genericOptions] [commandOptions]

使用练习：
（1）hadoop fs -ls /
出现错误：
原因：没有打开hdfs
解决：
(2)hadoop fs -put README.txt /

测试：

（3）hadoop fs -cat /README.txt
== hadoop fs -text /README.txt

(4) hadoop fs -copyFromLocal cdh_version.properties /
此时：
（5）hadoop fs -get /README.txt .
此时：

（6）hadoop fs -mkdir /hdfs-test
此时：
（7）hadoop fs -mv /README.txt /hdfs-test/
此时：

（8）hadoop fs -cp /hdfs-test/README.txt /hdfs-test/README.txt-bak
此时：
（9）hadoop fs -getmerge /hdfs-test ./t.txt
此时：

（10）hadoop fs -rm /cdh_version.properties
此时：