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From ishan chhabra <ishan.chha...@gmail.com>
Subject Re: Recovering fsImage from Namenode Logs
Date Thu, 20 Dec 2012 08:33:22 GMT
Unfortunately, the checkpoint image that I have has the deletes recorded. I
cannot use it. I do have an image that is 15 days old, which I am currently

I looked at the my logs and I have the filename, block allocated and
generation stamp. Can you explain to me the importance of the generation
stamp here? Since my hdfs cluster is operational with the old image and I
am writing new data to it, the generation stamp must have been incremented
beyond what it was 15 days ago. If I try to restore a block that we
written, lets say, 13 days ago, there can be generation stamp collision.
So, if I stop my cluster and make the new entries with generation stamp
increments after what is currently in the namenode, will it be ok? Is the
generation stamp stored somewhere in the datanode or the block stored in
the datanode?

Thanks for the clarifications.

On Wed, Dec 19, 2012 at 10:40 PM, Harsh J <harsh@cloudera.com> wrote:

> proper INode entries of them to append/recreate your fsimage. They are


Ishan Chhabra

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