title: RabbitMQ clusturing `join_cluster`
body: <p>I'm setting up a RabbitMQ cluster reading from its <a href="http://www.rabbitmq.com/clustering.html" rel="nofollow">docs</a>. </p>
  
  <p>While setting it up, it joins Machine2 with Machine1 via command <code>rabbitmqctl join_cluster rabbit@rabbit1</code>. Now what is <code>rabbit@rabbit1</code>? </p>
  
  <p>I know its <code>user@hostname</code>, but when I fire this command, it says <code>Error: {cannot_discover_cluster,"Cannot cluster node with itself"}</code>. </p>
  
  <p>When I type-in the IP instead of hostname, it says <code>Error: {cannot_discover_cluster,"The nodes provided are either offline or not running"}</code>. </p>
  
  <p>I've also added <code>IP rabbit1</code> in the <strong>/etc/hosts</strong> file as well.</p>
  
  <p>What  exactly am I missing here?</p>