HDFS free space available command

Try this:

hdfs dfsadmin -report

With older versions of Hadoop, try this:

hadoop dfsadmin -report

Methods

In newer versions of HDFS the hadoop CLI for dfsadmin is deprecated:

$ sudo -u hdfs hadoop dfsadmin -reportDEPRECATED: Use of this script to execute hdfs command is deprecated.Instead use the hdfs command for it.

So you should be using only hdfs at this point. Additionally when on systems where sudo is required you run it like so:

$ sudo -u hdfs hdfs dfsadmin -report

You have an additional method available via the fs module to hadoop as well:

$ hadoop fs -df -h

Example output

Also to provide a more thorough answer here's what the output would look like from a single node installation.

$ sudo -u hdfs hdfs dfsadmin -reportConfigured Capacity: 7504658432 (6.99 GB)Present Capacity: 527142912 (502.72 MB)DFS Remaining: 36921344 (35.21 MB)DFS Used: 490221568 (467.51 MB)DFS Used%: 93.00%Under replicated blocks: 128Blocks with corrupt replicas: 0Missing blocks: 0Missing blocks (with replication factor 1): 0-------------------------------------------------Live datanodes (1):Name: 192.168.114.48:50010 (host-192-168-114-48.td.local)Hostname: host-192-168-114-48.td.localDecommission Status : NormalConfigured Capacity: 7504658432 (6.99 GB)DFS Used: 490221568 (467.51 MB)Non DFS Used: 6977515520 (6.50 GB)DFS Remaining: 36921344 (35.21 MB)DFS Used%: 6.53%DFS Remaining%: 0.49%Configured Cache Capacity: 0 (0 B)Cache Used: 0 (0 B)Cache Remaining: 0 (0 B)Cache Used%: 100.00%Cache Remaining%: 0.00%Xceivers: 2Last contact: Thu Feb 04 13:35:04 EST 2016

In the above example, the HDFS HDD space has been 100% utilized.

That same system with the -df subcommand from the fs module:

$ hadoop fs -df -hFilesystem                                 Size     Used  Available  Use%hdfs://host-192-168-114-48.td.local:8020  7.0 G  467.5 M     18.3 M    7%

Hadoop version 1:

hadoop fs -df -h

OR

hadoop dfsadmin -report

Hadoop version 2:

hdfs dfs -df -h

OR

hadoop dfsadmin -report