root@master:~# hadoop fs -ls /
hadoop: command not found            //如果出现这种情况说明环境变量没有配置，执行一下操作

root@master:~# gedit .bashrc         //会弹出编辑框，然后添加如下文字
export HADOOP_HOME=/opt/hadoop-2.9.2
export PATH=${JAVA_HOME}/bin:$PATH
export PATH=${HADOOP_HOME}/bin:/opt/hadoop-2.9.2/sbin:$PATH

//save保存

root@master:~# source .bashrc          //重新加载文件（这一步必不可少）

root@master:~# hadoop fs -mkdir /test1 /test2        //同时创建两个文件，test1,test2
root@master:~# hadoop fs -ls /         //查看HDFS当前路径
Found 2 items
drwxr-xr-x   - root supergroup          0 2021-11-20 20:31 /test1
drwxr-xr-x   - root supergroup          0 2021-11-20 20:31 /test2
root@master:~# hadoop fs -mkdir -p /x/y/x      //创建目录/x/y/x
root@master:~# hadoop fs  -lsr /x              //查看x下面的目录
lsr: DEPRECATED: Please use 'ls -R' instead.
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y/x
root@master:~# hadoop fs -mkdir file:/home/hadoop/x        //hdfs下创建本地路径/home/hadoop/x
root@master:~# hadoop fs  -lsr /x                                // 查看x下的路径
lsr: DEPRECATED: Please use 'ls -R' instead.
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y/x
root@master:~# hadoop fs -ls /
Found 3 items
drwxr-xr-x   - root supergroup          0 2021-11-20 20:31 /test1
drwxr-xr-x   - root supergroup          0 2021-11-20 20:31 /test2
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x
root@master:~# ls
Desktop  Documents  Downloads  Music  Pictures  Public  Templates  Videos
root@master:~# cd 
root@master:~# ls
Desktop  Documents  Downloads  Music  Pictures  Public  Templates  Videos
root@master:~# cd
root@master:~# cd ..
root@master:/# ls
bin    dev   initrd.img      lib64       mnt   root  snap  tmp  vmlinuz
boot   etc   initrd.img.old  lost+found  opt   run   srv   usr  vmlinuz.old
cdrom  home  lib             media       proc  sbin  sys   var
root@master:/# cd home
root@master:/home# ls
hadoop
root@master:/home# hadoop fs  -touchz /test1/abc.txt
root@master:/home# hadoop fs  -ls /test1
Found 1 items
-rw-r--r--   3 root supergroup          0 2021-11-20 20:38 /test1/abc.txt
root@master:/home# echo "hello world" >> file1
root@master:/home# echo "hello old luo" >> file2
root@master:/home# ls
file1  file2  hadoop
root@master:/home# hadoop fs  -appendToFile file1 file2 /test1/abc.txt
root@master:/home# hadoop fs  -ls /test1/abc.txt
-rw-r--r--   3 root supergroup         26 2021-11-20 20:42 /test1/abc.txt
root@master:/home# hadoop fs  -cat /test1/abc.txt
hello world
hello old luo
root@master:/home# hadoop fs  -cp file:/home/hadoop/file1 /x
cp: `file:/home/hadoop/file1': No such file or directory
root@master:/home# cp file1 /home/hadoop
root@master:/home# ls
file1  file2  hadoop
root@master:/home# cd hadoop
root@master:/home/hadoop# ls
Desktop    Downloads         file1  Pictures  Templates  x
Documents  examples.desktop  Music  Public    Videos
root@master:/home/hadoop# hadoop fs  -cp file:/home/hadoop/file1 /x
root@master:/home/hadoop# hadoop fs  -lsr /x
lsr: DEPRECATED: Please use 'ls -R' instead.
-rw-r--r--   3 root supergroup         12 2021-11-20 20:50 /x/file1
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y/x
root@master:/home/hadoop# hadoop fs  -cp -p -f file:/home/hadoop/file1 /x
root@master:/home/hadoop# hadoop fs  -mv /x/file1 /x/file1.txt
root@master:/home/hadoop# hadoop fs  -lsr /x
lsr: DEPRECATED: Please use 'ls -R' instead.
-rw-r--r--   3 root root               12 2021-11-20 20:49 /x/file1.txt
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y
drwxr-xr-x   - root supergroup          0 2021-11-20 20:32 /x/y/x
root@master:/home/hadoop# hadoop fs  -lsr /text
lsr: DEPRECATED: Please use 'ls -R' instead.
lsr: `/text': No such file or directory
root@master:/home/hadoop# hadoop fs  -lsr /text1
lsr: DEPRECATED: Please use 'ls -R' instead.
lsr: `/text1': No such file or directory
root@master:/home/hadoop# cd ..
root@master:/home# ls
file1  file2  hadoop
root@master:/home# cd ..
root@master:/# ls
bin    dev   initrd.img      lib64       mnt   root  snap  tmp  vmlinuz
boot   etc   initrd.img.old  lost+found  opt   run   srv   usr  vmlinuz.old
cdrom  home  lib             media       proc  sbin  sys   var
root@master:/# hadoop fs -ls /
Found 3 items
drwxr-xr-x   - root supergroup          0 2021-11-20 20:38 /test1
drwxr-xr-x   - root supergroup          0 2021-11-20 20:31 /test2
drwxr-xr-x   - root supergroup          0 2021-11-20 20:54 /x
root@master:/# hadoop fs -ls /test1
Found 1 items
-rw-r--r--   3 root supergroup         26 2021-11-20 20:42 /test1/abc.txt
root@master:/# hadoop fs -mv /test1 /x/y
root@master:/# hadoop fs -ls /x
Found 2 items
-rw-r--r--   3 root root               12 2021-11-20 20:49 /x/file1.txt
drwxr-xr-x   - root supergroup          0 2021-11-20 20:58 /x/y
root@master:/# cd /x
bash: cd: /x: No such file or directory
root@master:/# cd x
bash: cd: x: No such file or directory
root@master:/# hadoop fs -ls x
ls: `x': No such file or directory
root@master:/# hadoop fs -ls /x
Found 2 items
-rw-r--r--   3 root root               12 2021-11-20 20:49 /x/file1.txt
drwxr-xr-x   - root supergroup          0 2021-11-20 20:58 /x/y
root@master:/# hadoop fs -ls /x/y
Found 2 items