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MapReduce >> mail # user >> Name node and data node replacement


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Re: Name node and data node replacement
Yes you are right. It will periodically checks the under replicated blocks
information and place those blocks on available data nodes if required.

Regards
Jitendra
On Wed, Dec 11, 2013 at 1:57 PM, oc tsdb <[EMAIL PROTECTED]> wrote:

> Hi,
>
> Thanks for your response.
>
> You mean NN will always try to maintain number of replicas as configured
> even if one DN goes down and unable to come up?
>
> Thanks
> -OC
>
>
>
> On Mon, Dec 9, 2013 at 8:18 PM, Daryn Sharp <[EMAIL PROTECTED]> wrote:
>
>> To recover a NN, you probably want to use the HA feature.  If not, try
>> writing your edits to a nfs volume in additional to the local fs.
>>
>> There is no need to recover a DN.  The NN compensates for a lost DN by
>> using the other remaining replicas to create a new replica on another DN.
>>
>> Daryn
>>
>> On Dec 9, 2013, at 5:52 AM, oc tsdb <[EMAIL PROTECTED]> wrote:
>>
>> > Hi,
>> >
>> > I am trying to understand,how to recover a Name node or Data node
>> failure in case if those nodes are unable to come up due to unexpected
>> issues.
>> >
>> > Is there a way to replace Name node with new name node without loosing
>> data.I mean new Name node should have all the data from original Name node.
>> > Similarly for Data node.
>> >
>> >
>> > Thanks
>> > -OC
>> >
>> >
>>
>>
>