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From: Harsh J <harsh@cloudera.com>
Date: Fri, 10 Feb 2012 17:17:51 +0530
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 <CAOcnVr2uCCkepH=7_4DN3oRCeZ06Tt=ZErWVQmEnNCx_ypqfog@mail.gmail.com>
Subject: Re: Which server store the root and .meta. information?
To: user@hbase.apache.org
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The HMaster does not host regions, and the -ROOT- is a region; It is
hosted by one of the assigned RegionServers, and its location is
registered under ZooKeeper. The -ROOT- region then holds the location
of the .META. (Which again, is another region, and is hosted by
RegionServers in just the same way).

For your ZK question, if you run ZK in HBase's embedded mode, it runs
on the HMaster, while if you run it standalone you can choose to run
it anywhere. The latter method is what is recommended for production
deployments, and its preferable to host it separately on its own
boxes.

P.s. The JIRA at https://issues.apache.org/jira/browse/HBASE-3171 may
simplify this someday :)

2012/2/10 yonghu <yongyong313@gmail.com>:
> Thanks!
> I know this. I just want to know which nodes store this information
> when the client first contact to HBase cluster, HMaster or
> RegionServer or a special node in which runs the zookeeper.
>
> And the other question is whether zookeeper runs on the same nodes as
> Hbase in the cluster or it  runs in a separate nodes?
>
> Yong
>
> On Fri, Feb 10, 2012 at 12:16 PM, Roger <rogerdai@qq.com> wrote:
>> To my knowledge, it is a three level tree-like structure.
>>  ------------------
>> =B8=C3=D3=CA=BC=FE=B4=D3=D2=C6=B6=AF=C9=E8=B1=B8=B7=A2=CB=CD
>>
>> ------------------ Original ------------------
>> From: "yonghu"<yongyong313@gmail.com>
>> Date: Fri, Feb 10, 2012 07:12 PM
>> To: "user"<user@hbase.apache.org>;
>> Subject: Which server store the root and .meta. information?
>>
>>
>> Hello,
>>
>> I read some articles which mention before the client connect to the
>> master node, he will first connect to the zookeeper node and find the
>> location of the root node. So, my question is that the node which
>> stores the root information is different from master node or they are
>> the same node?
>>
>> Thanks!
>>
>> Yong


--=20
Harsh J
Customer Ops. Engineer
Cloudera | http://tiny.cloudera.com/about