anchor.diff:  
   [float]
   [[master-node]]
  -=== Master Eligible Node
  +=== Master-eligible node
   
   The master node is responsible for lightweight cluster-wide actions such as
   creating or deleting an index, tracking which nodes are part of the cluster,
  
positive.code: [[modules-node]]
  == Node
  
  Any time that you start an instance of Elasticsearch, you are starting a
  _node_. A collection of connected nodes is called a
  <<modules-cluster,cluster>>. If you are running a single node of Elasticsearch,
  then you have a cluster of one node.
  
  Every node in the cluster can handle <<modules-http,HTTP>> and
  <<modules-transport,Transport>> traffic by default. The transport layer
  is used exclusively for communication between nodes; the HTTP layer is
  used by REST clients.
  
  All nodes know about all the other nodes in the cluster and can forward client
  requests to the appropriate node. 
  
negative.code: -------------------
  <1> The default for `node.voting_only` is `false`.
  
  IMPORTANT: The `voting_only` role requires the {default-dist} of {es} and is not
  supported in the {oss-dist}. If you use the {oss-dist} and set
  `node.voting_only` then the node will fail to start.  Also note that only
  master-eligible nodes can be marked as voting-only.
  
  