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Zookeeper >> mail # user >> Q about majority voting, # of nodes, even node number


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Q about majority voting, # of nodes, even node number
Hi,

Somebody asked me recently and I "got stuck" trying to explain this.
When people ask how many ZK nodes they should have a common answer is "odd
number: 3 or 5 or ...", so ZK can do majority voting.  Correct so far?
Another reason is for HA - if one ZK node dies, there are still 2 of them
left.  And this is where I am missing something core - with just 2 nodes
left, how can ZK do majority voting now?

Thanks,
Otis
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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