Answer / Rinku Rani

"Gen1 NameNode (First Generation)" was a single point of failure as it managed both metadata and data blocks. When it crashed, all the cluster data was lost.n"Gen2 NameNode (Second Generation)" introduced the NameNode High Availability (HA) feature by separating metadata management from storage. Now, there's a separate "secondary NameNode" that periodically takes a snapshot of the Namespace Information Tree (NSIT). In case of NameNode failure, the secondary node can be promoted to primary without data loss.

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