BigData / Hadoop basics

What is DataNode?

DataNode is a commodity hardware which actually stores the data and performs file-level operations as suggested by the NameNode. DataNode sends the signals to NameNode for its status. If DataNode is not able to send heartbeats to the NameNode than Name node marked particular DataNode as dead.

Slave daemons.
Serves read/write request from the client.
Stores actual data.

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BigData / Hadoop basics

What is DataNode?

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