title: Hierarchical quorums in Zookeeper
body: <p>I am trying to understand hierarchical quorums in Zookeeper. The documentation <a href="http://archive.cloudera.com/cdh5/cdh/5/zookeeper/zookeeperHierarchicalQuorums.html" rel="nofollow">here</a><br>
  gives an example but I am still not quiet sure I understand it. My question is, if I have a two node Zookeeper cluster (I know it is not recommended but let's consider it for the sake of this example) 
  <em>server.1</em> and 
  <em>server.2</em>, 
  can I have hierarchical quorums as follows: </p>
  
  <p><code>group.1=1:2
   weight.1=2
   weight.2=2
  </code></p>
  
  <p>With the above configuration:</p>
  
  <ol>
  <li><p>Even if one node goes down I still have enough votes (?) to
  maintain a quorum ? is this a correct statement ?</p></li>
  <li><p>What is the zookeeper quorum value here (2 - for two nodes or 3 -
  for 4 votes)</p></li>
  </ol>
  
  <p>In a second example, say I have: </p>
  
  <p><code>group.1=1:2
   weight.1=2
   weight.2=1
  </code> </p>
  
  <p>In this case if <em>server.2</em> goes down, </p>
  
  <ol start="3">
  <li>Should I still have sufficient votes (2) to maintain a quorum ? </li>
  </ol>