Public-works ops asks which Hadoop role holds the namespace metadata versus the actual block bytes for storm-drain sensor archives. Which distinction is correct?
Select an answer to reveal the explanation.
Short Explanation
Metadata is the map of the library; the shelves hold the books. On HDFS the NameNode keeps the namespace map, and DataNodes keep the block bytes. Mixing those jobs up breaks how the cluster finds storm-drain archives.
Full Explanation
In HDFS the NameNode maintains the file-system namespace and block-location metadata, while DataNodes store the actual block contents. ResourceManagers schedule compute; they do not replace DataNodes as the durable block store. Operators must know which role owns metadata versus bytes when troubleshooting municipal archives.