HDFS文件系统

• Hadoop fs 等价于 hdfs dfs  

[xiaoqiu@s150 bin]$ hdfs dfs
Usage: hadoop fs [generic options]

 fs                   run a generic filesystem user client

• 在HDFS文件系统创建文件夹

[xiaoqiu@s150 bin]$ cd ~
[xiaoqiu@s150 ~]$ ls
[xiaoqiu@s150 ~]$ hdfs dfs -mkdir -p ~/cr

• 在本地创建文件

[xiaoqiu@s150 ~]$ touch test.txt
[xiaoqiu@s150 ~]$ ls
test.txt
[xiaoqiu@s150 ~]$

• 将本地文件上传到HDFS文件系统

[xiaoqiu@s150 ~]$ hdfs dfs -put test.txt ~/cr
[xiaoqiu@s150 ~]$ hdfs dfs -ls ~/cr
Found 1 items
-rw-r--r--   2 xiaoqiu supergroup          0 2017-12-24 08:08 /home/xiaoqiu/cr/test.txt
[xiaoqiu@s150 ~]$

• 从HDFS文件系统下载到本地

[xiaoqiu@s150 ~]$ hdfs dfs -get ~/cr/test.txt a.txt
[xiaoqiu@s150 ~]$ ls
a.txt  test.txt
[xiaoqiu@s150 ~]$

• 查看HDFS文件系统

[xiaoqiu@s150 ~]$ hdfs dfs -ls -R ~/cr/
[xiaoqiu@s150 ~]$

• 追加文件到HDFS文件系统

[xiaoqiu@s150 ~]$ hdfs dfs -appendToFile b.txt ~/cr/test.txt
[xiaoqiu@s150 ~]$ hdfs dfs -lsr ~
lsr: DEPRECATED: Please use 'ls -R' instead.
drwxr-xr-x   - xiaoqiu supergroup          0 2017-12-24 08:40 /home/xiaoqiu/cr
-rw-r--r--   2 xiaoqiu supergroup          6 2017-12-24 08:40 /home/xiaoqiu/cr/test.txt
-rw-r--r--   2 xiaoqiu supergroup          6 2017-12-24 08:39 /home/xiaoqiu/cr.test.txt
[xiaoqiu@s150 ~]$ hdfs dfs -cat ~/cr/test.txt
hello
[xiaoqiu@s150 ~]$