Hi Jack,
I understood this concept. The DFS client is directly connected to
the datanodes in hdfs and perform the read/write block data with communicate
with the namenode by client protocol . Is there is no direct involvement of
namenode in the HBase operation ?
Thanks
R.Shanmuganathan
---- On Wed, 21 Sep 2011 12:55:37 +0530 Jack Levin<[email protected]>
wrote ----
The master will detect that RS is down by periodically checking a
zookeeper ( it will say in the master log, znode expired ). After, it
will check to see if there is anything in /hbase/.logs directory for
that region server, if something is found, master will replay the log
records and 'push' them into region directories, when master is done,
the 'unopened' regions will be opened by the rest of the region
servers and all regions that were down will be back online.
-Jack
On Wed, Sep 21, 2011 at 12:21 AM, shanmuganathan.r
<[email protected]> wrote:
> Hi All,
>
> I am running the HBase in fully distributed mode. I used the
HBase 0.90.2 version . I have one doubt , that one is what will happen when the
Region server is crashed ?
>
>
> If the one region is managed by one region server then what will happen
after the crash of the region server?
>
> Thanks in Advance....
>
>
> Regards
>
>
> R.Shanmuganathan
>
>
>
