DataNode
A DataNode is a fundamental component within distributed storage systems, most notably Hadoop's Hadoop Distributed File System (HDFS). Its primary role is to store and manage actual data blocks on disk. When a file is stored in HDFS, it is broken down into smaller, fixed-size blocks, typically 128MB or 256MB. Each DataNode is responsible for holding a subset of these blocks.
DataNodes communicate with a NameNode, which acts as the master server in HDFS. The NameNode maintains the
When a client requests to read a file, the NameNode tells the client which DataNodes hold the