HDFS (Distributed File Storage System)--Basic Commands
Table of contents
HDFS (Distributed File Storage System)--Basic Commands
1. Common commands
| Order |
illustrate |
| hadoop fs -mkdir /park |
In the root directory of hdfs, create a park directory |
| hadoop fs -ls / |
Check which directories are in the root directory of hdfs |
| hadoop fs -put /root/1.txt /park |
Put 1.txt in the root directory of the linux operating system in the park directory of hdfs |
| hadoop fs -get /park/jdk /home |
Download the files in the park directory under the hdfs file system to the home directory of linux |
| hadoop fs -rm /park/filename |
Delete the specified file in the park directory of hdfs |
| hadoop fs -rmdir /park |
Delete the park directory, but there are no files in the prerequisite directory |
| hadoop fs -rmr /park |
Delete the park directory, even if there are files in the directory |
| hadoop fs -cat /park/a.txt |
View the a.txt file in the park directory |
| hadoop fs -tail /park/a.txt |
View the data at the end of the a.txt file in the park directory |
| haddop jar xxx.jar |
Execute the jar package |
| hadoop fs -cat /park/result/part-r-00000 |
View the contents of the /park/result/part-r-00000 file |
| hadoop fs –mv /park02 /park01 |
Rename the park02 directory on HDFS to park01 command. |
| hadoop fs -mv /park02/1.txt /park01 |
Move 1.txt in the park02 directory to the /park01 directory |
| hadoop fs -touchz /park/2.txt |
create an empty file |
| hadoop fs -getmerge /park /root/tmp |
Merge all the files in the park directory into one file and download it to the tmp directory in the root directory of linux |
| hadoop dfsadmin -safemode leave |
exit hadoop safe mode |
| hadoop dfsadmin -safemode enter |
enter safe mode |
| hadoop dfsadmin -rollEdits |
Manually perform fsimage file and Edis file merge metadata |
| hadoop dfsadmin -report |
View surviving datanode node information |
| hadoop fsck /park |
Report the health status of the /park directory |
| hadoop fsck /park/1.txt -files -blocks -locations -racks |
View 1.txt file block information and rack information
|
| hadoop fs -expunge |
Manually empty the hdfs recycle bin |
2. Other commands
| Order |
illustrate |
| hadoop fs -cp /park01/1.txt /park02 |
Copy 1.txt under /park01 on HDFS to the /park02 directory. |
| hadoop fs -du /park/1.txt |
View the size of a file on HDFS. You can also view the specified directory, if it is a directory, list all the files and their sizes in the directory, for example: hadoop fs -du /park |
| hadoop fs -copyFromLocal /home/1.txt /park01 |
Upload the local file 1.txt to the /park01 directory |
| hadoop fs -copyToLocal /park01/1.txt /home |
Copy 1.txt on HDFS to the local file system |
| hadoop fs -lsr / |
Recursively view all content in the specified directory |