Explain HDFS architecture in detail

Updated May 16, 2026

Short answer

HDFS uses NameNode, DataNodes, and secondary nodes for distributed storage.

Deep explanation

NameNode manages metadata, DataNodes store blocks, and Secondary NameNode helps with checkpoints. Data is split, replicated, and distributed.

Real-world example

Large-scale log storage systems in enterprises.

Common mistakes

  • Confusing Secondary NameNode with standby NameNode.

Follow-up questions

  • What is checkpoint node?
  • How is metadata stored?

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