How HDFS works

An HDFS cluster is comprised of a NameNode, which manages the cluster metadata, and DataNodes that store the data. Files and directories are represented on the NameNode by inodes. Inodes record attributes like permissions, modification and access times, or namespace and disk space quotas.

The file content is split into large blocks (typically 128 megabytes), and each block of the file is independently replicated at...

How HDFS works