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From: Harsh J <harsh@cloudera.com>
Date: Wed, 30 Jan 2013 21:57:30 +0530
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 <CAOcnVr3E1qm9Ke7cUZjvhU+9CuBtW6HXgKi9RudUMZMU=YAfow@mail.gmail.com>
Subject: Re: what will happen when HDFS restarts but with some dead nodes
To: "<user@hadoop.apache.org>" <user@hadoop.apache.org>
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NN does recalculate new replication work to do due to unavailable
replicas ("under-replication") when it starts and receives all block
reports, but executes this only after out of safemode. When in
safemode, across the HDFS services, no mutations are allowed.

On Wed, Jan 30, 2013 at 8:34 AM, Nan Zhu <zhunansjtu@gmail.com> wrote:
> Hi, all
>
> I'm wondering if HDFS is stopped, and some of the machines of the cluster
> are moved,  some of the block replication are definitely lost for moving
> machines
>
> when I restart the system, will the namenode recalculate the data
> distribution?
>
> Best,
>
> --
> Nan Zhu
> School of Computer Science,
> McGill University
>
>


-- 
Harsh J