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  • Eric Brosch thinks this is interesting:

As if by some cruel joke, the default value of dfs.name.dir is hadoop.tmp.dir/dfs/name and, when coupled with hadoop.tmp.dir’s default of /tmp/hadoop-user.name, lands the filesystem metadata squarely in a volatile directory. Many new to Hadoop have quickly setup Hadoop, missed setting dfs.name.dir, and found themselves with an unusable filesystem after rebooting the namenode because /tmp was cleared during boot. If there...

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Cover of Hadoop Operations

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