How to view files in HDFS (hadoop fs -ls)

Introduction

The hadoop fs -ls command allows you to view the files and directories in your HDFS filesystem, much as the ls command works on Linux / OS X / *nix.

Default Home Directory in HDFS
A user’s home directory in HDFS is located at /user/userName. For example, my home directory is /user/akbar.

List the Files in Your Home Directory

hadoop fs -ls defaults to /user/userName, so you can leave the path blank to view the contents of your home directory.

hadoop fs -ls

Recursively List Files

The following command will recursively list all files in the /tmp/hadoop-yarn directory.

hadoop fs -ls -R /tmp/hadoop-yarn

Show List Output in Human Readable Format

Human readable format will show each file’s size, such as 1461, as 1.4k.

hadoop fs -ls -h /user/akbar/input

You will see output similar to:
-rw-r–r–   1 akbar akbar       1.4k 2012-06-25 16:45 /user/akbar/input/core-site.xml
-rw-r–r–   1 akbar akbar       1.8k 2012-06-25 16:45 /user/akbar/input/hdfs-site.xml
-rw-r–r–   1 akbar akbar       1.3k 2012-06-25 16:45 /user/akbar/input/mapred-site.xml
-rw-r–r–   1 akbar akbar       2.2k 2012-06-25 16:45 /user/akbar/input/yarn-site.xml

List Information About a Directory

By default, hadoop fs -ls shows the contents of a directory. But what if you want to view information about the directory, not the directory’s contents?

To show information about a directory, use the -d option.

hadoop fs -ls -d /user/akbar

Output:
drwxr-xr-x   – akbar akbar          0 2012-07-07 02:28 /user/akbar/

Compare the output above to the output without the -d option:
drwxr-xr-x   – akbar akbar          0 2012-06-25 16:45 /user/akbar/input
drwxr-xr-x   – akbar akbar          0 2012-06-25 17:09 /user/akbar/output
-rw-r–r–   1 akbar akbar          3 2012-07-07 02:28 /user/akbar/text.hdfs

Show the Usage Statement

hadoop fs -usage ls

The output will be:

Usage: hadoop fs [generic options] -ls [-d] [-h] [-R] [ ...]

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