HDFS: Useful Hadoop Admin Commands

HDFS is designed more for batch processing rather than interactive use by users. The emphasis is on high throughput of data access rather than low latency of data access.

Applications that run on HDFS have large data sets. A typical file in HDFS is gigabytes to terabytes in size. Thus, HDFS is tuned to support large files. 

HDFS categorises its data in files and directories.It provides a command line interface called the FS shell that lets the user interact with data in the HDFS and manage your hadoop cluster.

This article provides a quick handy reference to all commonly used hadoop fs commands that can be used to manage files on a Hadoop cluster.The syntax of the commands is similar to bash and csh.

Check more about -HDFSand MapReduce

File transferring from local to HDFS

Hadoop fs –put

File transferring from HDFS to Local

Hadoop fs –get

File transferring within the HDFS

Hadoop fs –cp

List of the File Display inside the HDFS

Hadoop fs –ls

Display the content in the File within HDFS

Hadoop fs –cat

Remove particular File in HDFS

Hadoop fs –rm

Remove File directory in HDFS

Hadoop fs –rmr

Display the File size

Hadoop fs –du <File_name>

Display the directory size

Hadoop fs –dus <directory_name>

Create new directory in HDFS

Hadoop fs –mkdir <directory_name>

Display the whole directory and its content in HDFS

Hadoop fs –lsr <directory_name>

Displays last kilobyte of the File

Hadoop fs –tail <File_name>

Display the overview of HDFS

Hadoop fsck

File transferring from local to HDFS

Hadoop fs -CopyFromLocal

File transferring from HDFS to Local

Hadoop fs –CopyToLocal