Hadoop 常用shell命令

Hadoop 常用shell命令

1. 文件操作

• 查看文件
  ​​​hadoop fs -ls /​​

[root@server4 logs]# hadoop fs -ls /
Found 2 items
drwxr-xr-x   - root supergroup          0 2018-12-18 11:25 /hbase
drwxr-xr-x   - root supergroup          0 2018-12-22 08:24 /input

• 创建文件夹
  ​​​hadoop fs -mkdir /input​​

[root@server4 logs]# hadoop fs -mkdir /test
[root@server4 logs]# hadoop fs -ls /
Found 3 items
drwxr-xr-x   - root supergroup          0 2018-12-18 11:25 /hbase
drwxr-xr-x   - root supergroup          0 2018-12-22 08:24 /input
drwxr-xr-x   - root supergroup          0 2018-12-22 08:27 /test

• 删除文件夹/文件

[root@server4 logs]# hadoop fs -rm -R /test
18/12/22 08:28:12 INFO fs.TrashPolicyDefault: Namenode trash configuration: Deletion interval = 0 minutes, Emptier interval = 0 minutes.
Deleted /test
[root@server4 logs]# hadoop fs -ls /
Found 2 items
drwxr-xr-x   - root supergroup          0 2018-12-18 11:25 /hbase
drwxr-xr-x   - root supergroup          0 2018-12-22 08:24 /input

• 使用hdfs dfs 上传一个文件到指定目录下：

[root@server4 temp]# hdfs dfs -put data.txt /input/
[root@server4 temp]# hdfs dfs -ls /input/
Found 1 items
-rw-r--r--   3 root supergroup        108 2018-12-22 08:32 /input/data.txt
[root@server4 temp]# cat data.txt 
hadoop is a good platform to analyze big data in disk.
spark is a perfet tool to deal with big data in RAM.