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Posted to mapreduce-user@hadoop.apache.org by Bharath Kumar <bh...@gmail.com> on 2014/05/12 09:18:24 UTC

LVM to JBOD conversion without data loss

Hi I am a query regarding JBOD ,

I sit possible to migrate from LVM to JBOD without loosing data ? Is there
any reference documentation ?

The steps which i can think of is

1) reduce the replication

2) change the hdfs-site.xml in namenode

3) add the data node back with new JBOD directory structure for haddop

4) rebalance the cluster

repeat 1 -4 for all data nodes is the steps correct ?

-- 
Warm Regards,
                         *Bharath Kumar *

Re: LVM to JBOD conversion without data loss

Posted by Ravi Prakash <ra...@ymail.com>.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

One way I can think of is decomissioning the nodes and then basically
re-imaging it however you want to. Is that not an option?

On 05/12/14 00:18, Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is there
> any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>

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Re: LVM to JBOD conversion without data loss

Posted by Akira AJISAKA <aj...@oss.nttdata.co.jp>.
Hi Bharath,

The steps are not correct for me. Data loss can happen if you reduce the 
replication and remove a DataNode at the same time.

1) decomission a DataNode (or some DataNodes)

2) change the configuration of the DataNode(s)

3) add the DataNode(s) to the cluster

repeat 1) - 3) for all the DataNodes.

Regards,
Akira

(2014/05/12 16:18), Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is
> there any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>
> --
> Warm Regards,
> /Bharath Kumar /
>


Re: LVM to JBOD conversion without data loss

Posted by Ravi Prakash <ra...@ymail.com>.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

One way I can think of is decomissioning the nodes and then basically
re-imaging it however you want to. Is that not an option?

On 05/12/14 00:18, Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is there
> any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>

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Version: GnuPG v1
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/

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Re: LVM to JBOD conversion without data loss

Posted by Ravi Prakash <ra...@ymail.com>.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

One way I can think of is decomissioning the nodes and then basically
re-imaging it however you want to. Is that not an option?

On 05/12/14 00:18, Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is there
> any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/

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Re: LVM to JBOD conversion without data loss

Posted by Ravi Prakash <ra...@ymail.com>.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

One way I can think of is decomissioning the nodes and then basically
re-imaging it however you want to. Is that not an option?

On 05/12/14 00:18, Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is there
> any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/

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Re: LVM to JBOD conversion without data loss

Posted by Akira AJISAKA <aj...@oss.nttdata.co.jp>.
Hi Bharath,

The steps are not correct for me. Data loss can happen if you reduce the 
replication and remove a DataNode at the same time.

1) decomission a DataNode (or some DataNodes)

2) change the configuration of the DataNode(s)

3) add the DataNode(s) to the cluster

repeat 1) - 3) for all the DataNodes.

Regards,
Akira

(2014/05/12 16:18), Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is
> there any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>
> --
> Warm Regards,
> /Bharath Kumar /
>


Re: LVM to JBOD conversion without data loss

Posted by Akira AJISAKA <aj...@oss.nttdata.co.jp>.
Hi Bharath,

The steps are not correct for me. Data loss can happen if you reduce the 
replication and remove a DataNode at the same time.

1) decomission a DataNode (or some DataNodes)

2) change the configuration of the DataNode(s)

3) add the DataNode(s) to the cluster

repeat 1) - 3) for all the DataNodes.

Regards,
Akira

(2014/05/12 16:18), Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is
> there any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>
> --
> Warm Regards,
> /Bharath Kumar /
>


Re: LVM to JBOD conversion without data loss

Posted by Akira AJISAKA <aj...@oss.nttdata.co.jp>.
Hi Bharath,

The steps are not correct for me. Data loss can happen if you reduce the 
replication and remove a DataNode at the same time.

1) decomission a DataNode (or some DataNodes)

2) change the configuration of the DataNode(s)

3) add the DataNode(s) to the cluster

repeat 1) - 3) for all the DataNodes.

Regards,
Akira

(2014/05/12 16:18), Bharath Kumar wrote:
> Hi I am a query regarding JBOD ,
>
> I sit possible to migrate from LVM to JBOD without loosing data ? Is
> there any reference documentation ?
>
> The steps which i can think of is
>
> 1) reduce the replication
>
> 2) change the hdfs-site.xml in namenode
>
> 3) add the data node back with new JBOD directory structure for haddop
>
> 4) rebalance the cluster
>
> repeat 1 -4 for all data nodes is the steps correct ?
>
> --
> Warm Regards,
> /Bharath Kumar /
>