> For the complete documentation index, see [llms.txt](https://george-jen.gitbook.io/data-science-and-apache-spark/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://george-jen.gitbook.io/data-science-and-apache-spark/hdfs.md).

# HDFS

### HDFS

Once hadoop single node cluster has been setup it’s time to initialize HDFS file system by formatting the /mnt/common/hdfs/namenode storage directory with the following command:

$ hdfs namenode -format

Now ready to start Hadoop instance. Before starting, recommend you to log out and log back in to update the environment variables.