hdfs客户端的常用操作命令
0、查看hdfs中的目录信息

hadoop fs -ls /hdfs路径

1、上传文件到hdfs中

hadoop fs -put /本地文件  /aaa
hadoop fs -copyFromLocal /本地文件  /hdfs路径   ##  copyFromLocal等价于 put
hadoop fs -moveFromLocal /本地文件  /hdfs路径  ## 跟copyFromLocal的区别是：从本地移动到hdfs中

2、下载文件到客户端本地磁盘

hadoop fs -get /hdfs中的路径   /本地磁盘目录
hadoop fs -copyToLocal /hdfs中的路径 /本地磁盘路径   ## 跟get等价
hadoop fs -moveToLocal /hdfs路径  /本地路径  ## 从hdfs中移动到本地

3、在hdfs中创建文件夹

hadoop fs -mkdir  -p /aaa/xxx

4、移动hdfs中的文件（更名）

hadoop fs -mv /hdfs的路径  /hdfs的另一个路径

5、删除hdfs中的文件或文件夹

hadoop fs -rm -r /aaa

6、修改文件的权限

hadoop fs -chown user:group /aaa
hadoop fs -chmod 700 /aaa

7、追加内容到已存在的文件

hadoop fs -appendToFile /本地文件   /hdfs中的文件

8、显示文本文件的内容

hadoop fs -cat /hdfs中的文件
hadoop fs -tail /hdfs中的文件

hdfs命令行客户端的所有命令列表

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] [-d] <localsrc> ... <dst>]
        [-copyToLocal [-f] [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
        [-count [-q] [-h] [-v] [-t [<storage type>]] [-u] [-x] <path> ...]
        [-cp [-f] [-p | -p[topax]] [-d] <src> ... <dst>]
        [-createSnapshot <snapshotDir> [<snapshotName>]]
        [-deleteSnapshot <snapshotDir> <snapshotName>]
        [-df [-h] [<path> ...]]
        [-du [-s] [-h] [-x] <path> ...]
        [-expunge]
        [-find <path> ... <expression> ...]
        [-get [-f] [-p] [-ignoreCrc] [-crc] <src> ... <localdst>]
        [-getfacl [-R] <path>]
        [-getfattr [-R] {-n name | -d} [-e en] <path>]
        [-getmerge [-nl] [-skip-empty-file] <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] [-d] <localsrc> ... <dst>]
        [-renameSnapshot <snapshotDir> <oldName> <newName>]
        [-rm [-f] [-r|-R] [-skipTrash] [-safely] <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> ...]
        [-truncate [-w] <length> <path> ...]
        [-usage [cmd ...]]