@Harry Li When a file is deleted by a user or an application, it is not immediately removed from HDFS. Instead, HDFS first renames it to a file in the /trash directory. The file can be restored quickly as long as it remains in /trash. The retention time in the /trash is configurable. After the expiry of its life in /trash, the NameNode deletes the file from the HDFS namespace. The deletion of a file causes the blocks associated with the file to be freed. Note that there could be an appreciable time delay between the time a file is deleted by a user and the time of the corresponding increase in free space in HDFS. If you want to change the default setting then it needs to be updated in the core-site properties, which you can find in the Ambari menu. Simply follow this path; from the Ambari Dashboard, click HDFS -> Configs -> Advanced -> Advanced core-site. Then set the 'fs.trash.interval' to 0 to disable. This will require a restart of the related components to pick up the changes. Check the HDFS structure to see where the most data is held. This will give you the space on each data node $ hdfs dfsadmin -report Breakdown of the HDFS across the cluster and each of the data nodes run the below command, you should give it some time to complete. $ hdfs dfs -expunge By default, HDFS uses trash. You can bypass this with rm -skipTrash or just delete the trash with The other option when cleaning up your data use the -skipTrash flag: $ hdfs dfs -rm -R -skipTrash /folder-path HTH
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