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From Harsh J <ha...@cloudera.com>
Subject Re: could only be replicated to 0 nodes, instead of 1
Date Wed, 05 Sep 2012 02:41:05 GMT

The NameNode has a resource-checker thread in it by design to help
prevent cases of on-disk metadata corruption in event of filled up
dfs.namenode.name.dir disks, etc.. By default, an NN will lock itself
up if the free disk space (among its configured metadata mounts)
reaches a value < 100 MB, controlled by
dfs.namenode.resource.du.reserved. You can probably set that to 0 if
you do not want such an automatic preventive measure. Its not exactly
a need, just a check to help avoid accidental data loss due to
non-monitoring of disk space.

On Tue, Sep 4, 2012 at 11:33 PM, Keith Wiley <kwiley@keithwiley.com> wrote:
> I had moved the data directory to the larger disk but left the namenode directory on
the smaller disk figuring it didn't need much room.  Moving that to the larger disk seems
to have improved the situation...although I'm still surprised the NN needed so much room.
> Problem is solved for now.
> Thanks.
> ________________________________________________________________________________
> Keith Wiley     kwiley@keithwiley.com     keithwiley.com    music.keithwiley.com
> "I used to be with it, but then they changed what it was.  Now, what I'm with
> isn't it, and what's it seems weird and scary to me."
>                                            --  Abe (Grandpa) Simpson
> ________________________________________________________________________________

Harsh J

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