data node failure & restart

[Wenhao Xu <xu...@gmail.com>]

Hi all,
   I am new to HDFS and have a basic question to ask. Thanks in advance.
   When a data node failed over, the name server will detect this and may
make replica decisions. However, what if the failed node is restarted later
and report to the name server again? Will this make too many replicas exist?
   Thanks!

regards,
Wenhao

-- 
~_~

Re: data node failure & restart

[Wenhao Xu <xu...@gmail.com>]

Thanks!
What happens if the network partition occurs? Will all the nodes
disconnecting from the name server will reports their data chunks to the
name server again after the network come back?

And what if only the network of name server is broken only? What is the name
server and data server 's reactions then?

cheers,
W.

On Wed, Aug 4, 2010 at 8:53 PM, Ken <ke...@gmail.com> wrote:

> Yes, but eventually over replicated blocks will be deleted.
>
> Sent from my iPad
>
> On Aug 4, 2010, at 8:41 PM, Wenhao Xu <xu...@gmail.com> wrote:
>
> > Hi all,
> >   I am new to HDFS and have a basic question to ask. Thanks in advance.
> >   When a data node failed over, the name server will detect this and may
> > make replica decisions. However, what if the failed node is restarted
> later
> > and report to the name server again? Will this make too many replicas
> exist?
> >   Thanks!
> >
> > regards,
> > Wenhao
> >
> > --
> > ~_~
>



-- 
~_~

Re: data node failure & restart

[Ken <ke...@gmail.com>]

Yes, but eventually over replicated blocks will be deleted. 

Sent from my iPad

On Aug 4, 2010, at 8:41 PM, Wenhao Xu <xu...@gmail.com> wrote:

> Hi all,
>   I am new to HDFS and have a basic question to ask. Thanks in advance.
>   When a data node failed over, the name server will detect this and may
> make replica decisions. However, what if the failed node is restarted later
> and report to the name server again? Will this make too many replicas exist?
>   Thanks!
> 
> regards,
> Wenhao
> 
> -- 
> ~_~