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question about ZKFC daemon
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,