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Shell operation of HDFS (notes)

Shulou Source: shulou.com Published: 2022-06-03 05:07:05 10月04日 Update

* basic operation (single cluster): *

1. Create folder command

[hadoop@master] $hadoop fs-mkdir-p / 20191021

2. Upload file command

[hadoop@master ~] $hadoop fs-put test.txt / 20191021

3. View file command

[hadoop@master ~] $hadoop fs-cat / 20191021/test.txt

4. File copy command (copy to local)

[hadoop@master ~] $hadoop fs-get / 20191021/test.txt

5. Check the file directory under the directory

[hadoop@master ~] $hadoop fs-ls / 20191021

6. Delete file command

[hadoop@master ~] $hadoop fs-rm / 20191021/test.txt

7. Delete folder command

[hadoop@master ~] $hadoop fs-rmr / 20191021

Common operation commands for administrators:

1. View the running Job

[hadoop@master ~] $hadoop job-list

2. Close the running Job

[hadoop@master ~] $hadoop job-kill (name of the running job)

3. Check the status of the HDFS block to see if it is damaged

[hadoop@master ~] $hadoop fsck

4. Check the status of HDFS blocks and delete damaged blocks

[hadoop@master ~] $hadoop fsck /-delete

5. Check the status of HDFS blocks, including DataNode information

[hadoop@master ~] $hadoop dfsadmin-report

6. Hadoop enters safe mode

[hadoop@master ~] $hadoop dfsadmin-safemode enter

7. Hadoop leaves safe mode

[hadoop@master ~] $hadoop dfsadmin-safemode leave

8. Balance the files in the cluster

[hadoop@master hadoop] $sbin/start-balancer.sh