Hadoop node disk failure - reinstall question

[Mayuran Yogarajah <ma...@casalemedia.com>]

One of our nodes died today, it looks like the disk containing the OS 
expired.  I will need to reinstall the machine.
Are there any known issues with using the same hostname / IP again, or 
is it better to give it a new IP / host name ?

The second disk on the machine is still operational and contains HDFS 
data so I plan on mounting it.  Is this ill-advised? Should I just wipe 
that disk too ?

thanks,
M

Re: Hadoop node disk failure - reinstall question

[Uma Maheswara Rao G 72686 <ma...@huawei.com>]

----- Original Message -----
From: Mayuran Yogarajah <ma...@casalemedia.com>
Date: Tuesday, October 18, 2011 4:24 am
Subject: Hadoop node disk failure - reinstall question
To: "common-user@hadoop.apache.org" <co...@hadoop.apache.org>

> One of our nodes died today, it looks like the disk containing the 
> OS 
> expired.  I will need to reinstall the machine.
> Are there any known issues with using the same hostname / IP again, 
> or 
> is it better to give it a new IP / host name ?
> 
> The second disk on the machine is still operational and contains 
> HDFS 
> data so I plan on mounting it.  Is this ill-advised? Should I just 
> wipe 
> that disk too ?
Copying that data to new machine would be good option. It is gain depending on the replication. If you have enough replicas in your cluster. then automatically replication will happen to new nodes. In that case you need not even worry about old data. 
> 
> thanks,
> M
> 

Re: Hadoop node disk failure - reinstall question

[patrick sang <si...@gmail.com>]

This is what i would think:

> Are there any known issues with using the same hostname / IP again, or is
it better to give it a new IP / host name ?
as far as i understand, it is actually good to keep the same hostname/ip
because the TTL in both dns or client library would bite you.

> The second disk on the machine is still operational and contains HDFS data
so I plan on mounting it.
I think it should be fine because by the time that you start the datanode,
it will report to namenode what blocks it has.



On Mon, Oct 17, 2011 at 3:53 PM, Mayuran Yogarajah <
mayuran.yogarajah@casalemedia.com> wrote:

> One of our nodes died today, it looks like the disk containing the OS
> expired.  I will need to reinstall the machine.
> Are there any known issues with using the same hostname / IP again, or is
> it better to give it a new IP / host name ?
>
> The second disk on the machine is still operational and contains HDFS data
> so I plan on mounting it.  Is this ill-advised? Should I just wipe that disk
> too ?
>
> thanks,
> M
>