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HDFS, mail # user - question about ZKFC daemon


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ESGLinux 2012-12-27, 12:03
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rahul p 2012-12-28, 07:00
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Harsh J 2012-12-27, 16:34
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Re: question about ZKFC daemon
ESGLinux 2012-12-28, 09:25
Hi,

well, If I have understand you I can configure my NN HA cluster this way:

- Active NameNode + 1 ZKFC daemon + Journal Node
- Standby NameNode + 1 ZKFC daemon + Journal Node
- JobTracker node + 1 ZKFC daemon + Journal Node,

Is this right?

Thanks in advance,

ESGLinux,

2012/12/27 Harsh J <[EMAIL PROTECTED]>

> Hi,
>
> There are two different things here: Automatic Failover and Quorum
> Journal Manager. The former, used via a ZooKeeper Failover Controller,
> is to manage failovers automatically (based on health checks of NNs).
> The latter, used via a set of Journal Nodes, is a medium of shared
> storage for namesystem transactions that helps enable HA.
>
> In a typical deployment, you want 3 or more (odd) JournalNodes for
> reliable HA, preferably on nodes of their own if possible (like you
> would for typical ZooKeepers, and you may co-locate with those as
> well) and one ZKFC for each NameNode (connected to the same ZK
> quorum).
>
> On Thu, Dec 27, 2012 at 5:33 PM, ESGLinux <[EMAIL PROTECTED]> wrote:
> > Hi all,
> >
> > I have a doubt about how to deploy the Zookeeper in a NN HA  cluster,
> >
> > As far as I know, I need at least three nodes to run three ZooKeeper
> > FailOver Controller (ZKFC). I plan to put these 3 daemons this way:
> >
> > - Active NameNode + 1 ZKFC daemon
> > - Standby NameNode + 1 ZKFC daemon
> > - JobTracker node + 1 ZKFC daemon, (is this right?)
> >
> > so the quorum is formed with these three nodes. The nodes that runs a
> > namenode are right because the ZKFC monitors it, but what does the third
> > daemon?
> >
> > as I read from this url:
> >
> https://ccp.cloudera.com/display/CDH4DOC/Software+Configuration+for+Quorum-based+Storage#SoftwareConfigurationforQuorum-basedStorage-AutomaticFailoverConfiguration
> >
> > this daemons are only related with NameNodes, (Health monitoring - the
> ZKFC
> > pings its local NameNode on a periodic basis with a health-check
> command.)
> > so what does the third ZKFC? I used the jobtracker node but I could use
> > another node without any daemon on it...
> >
> > Thanks in advance,
> >
> > ESGLInux,
> >
> >
> >
>
>
>
> --
> Harsh J
>
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Craig Munro 2012-12-28, 10:08
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ESGLinux 2012-12-28, 10:37
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Craig Munro 2012-12-28, 10:51
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ESGLinux 2012-12-28, 11:02
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Colin McCabe 2013-01-14, 19:49
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Colin McCabe 2013-01-14, 20:34
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ESGLinux 2013-01-15, 09:53
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Harsh J 2013-01-15, 09:55
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ESGLinux 2013-01-15, 10:08
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Harsh J 2013-01-15, 10:11
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ESGLinux 2013-01-15, 10:17