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From: "David Parks" <davidparks21@yahoo.com>
To: <user@hadoop.apache.org>
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Subject: RE: For a new installation: use the BackupNode or the CheckPointNode?
Date: Wed, 27 Mar 2013 10:28:49 +0700
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Thanks for the update, I understand now that I'll be installing a "secondary
name node" which performs checkpoints on the primary name node and keeps a
working backup copy of the fsimage file. 

The primary name node should write its fsimage file to at least 2 different
physical mediums for improved safety as well (example: locally and an nfs
share).

One point of query: were the primary name node to be lost, we would be best
off re-building it and copying the fsimage files into place, either from the
nfs share, or from the secondary name node, as the situation dictates.
There's no mechanism to "fail over" to the "secondary name node" per-se.

Am I on track here?

Thanks!
David


-----Original Message-----
From: Konstantin Shvachko [mailto:shv.hadoop@gmail.com] 
Sent: Wednesday, March 27, 2013 5:07 AM
To: user@hadoop.apache.org
Cc: davidparks21@yahoo.com
Subject: Re: For a new installation: use the BackupNode or the
CheckPointNode?

There is no BackupNode in Hadoop 1.
That was a bug in documentation.

Here is the updated link:
http://hadoop.apache.org/docs/r1.1.2/hdfs_user_guide.html

Thanks,
--Konstantin

On Sat, Mar 23, 2013 at 12:04 AM, varun kumar <varun.uid@gmail.com> wrote:
> Hope below link will be useful..
>
> http://hadoop.apache.org/docs/stable/hdfs_user_guide.html
>
>
> On Sat, Mar 23, 2013 at 12:29 PM, David Parks <davidparks21@yahoo.com>
> wrote:
>>
>> For a new installation of the current stable build (1.1.2 ), is there 
>> any reason to use the CheckPointNode over the BackupNode?
>>
>>
>>
>> It seems that we need to choose one or the other, and from the docs 
>> it seems like the BackupNode is more efficient in its processes.
>
>
>
>
> --
> Regards,
> Varun Kumar.P