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HBase >> mail # user >> Which server store the root and .meta. information?


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Re: Which server store the root and .meta. information?
Thanks for your reply. If the -ROOT- and .META. tables are managed by
two RegionServer separately. What is the functionality of Master node?
It only assigns the Region node in the cluster? So, the client only
needs to contact with these two special RegionServer which contains
the -ROOT- and .META. tables. If the interaction model is like what I
said, the client will not contact with master node!  If I am wrong,
let me know.

Thanks

Yong

On Fri, Feb 10, 2012 at 12:47 PM, Harsh J <[EMAIL PROTECTED]> wrote:
> 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 <[EMAIL PROTECTED]>:
>> 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 <[EMAIL PROTECTED]> wrote:
>>> To my knowledge, it is a three level tree-like structure.
>>>  ------------------
>>> 该邮件从移动设备发送
>>>
>>> ------------------ Original ------------------
>>> From: "yonghu"<[EMAIL PROTECTED]>
>>> Date: Fri, Feb 10, 2012 07:12 PM
>>> To: "user"<[EMAIL PROTECTED]>;
>>> 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
>
>
>
> --
> Harsh J
> Customer Ops. Engineer
> Cloudera | http://tiny.cloudera.com/about
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB