title: Upgrade Elasticsearch 1.4.1 to 2.0 same config fails
body: <p>I upgraded and copied my old config dir to the new version. I don't care about the old indexes so started fresh. The only things I had changed from default config were the host ip and cluster name.</p>
  
  <pre><code>network.host: 127.0.0.1
  cluster.name: elasticsearch_pat
  </code></pre>
  
  <p>I was running a single node on my dev machine with a custom cluster name so I'd have no conflict. Now when I launch ES I get continuous cluster/nodes/info error which throw a java.lang.IllegalStateException.</p>
  
  <pre><code>[2015-11-13 10:13:59,347][WARN ][transport.netty          ] [Entropic Man] exception caught on transport layer [[id: 0x6c3170dc, /127.0.0.1:61104 =&gt; /127.0.0.1:9300]], closing connection
  java.lang.IllegalStateException: Message not fully read (request) for requestId [109], action [cluster/nodes/info], readerIndex [39] vs expected [57]; resetting
      at org.elasticsearch.transport.netty.MessageChannelHandler.messageReceived(MessageChannelHandler.java:120)
      at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
      at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
      at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791)
      at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:296)
      at org.jboss.netty.handler.codec.frame.FrameDecoder.unfoldAndFireMessageReceived(FrameDecoder.java:462)
      at org.jboss.netty.handler.codec.frame.FrameDecoder.callDecode(FrameDecoder.java:443)
      at org.jboss.netty.handler.codec.frame.FrameDecoder.messageReceived(FrameDecoder.java:303)
      at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
      at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
      at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791)
      at org.elasticsearch.common.netty.OpenChannelsHandler.handleUpstream(OpenChannelsHandler.java:75)
      at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
      at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:559)
      at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:268)
      at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:255)
      at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:88)
      at org.jboss.netty.channel.socket.nio.AbstractNioWorker.process(AbstractNioWorker.java:108)
      at org.jboss.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:337)
      at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:89)
      at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:178)
      at org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108)
      at org.jboss.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:745)
  </code></pre>
  
  <p>When I check _health with Sense, it is green with one node and one data node, which is correct since I'm running on a dev machine on localhost.</p>
  
  <p>Does Elasticsearch now require authentication? Is this extremely simple config now somehow not sufficient?</p>
  
  <p><strong>Update:</strong> This error is coming because another process is trying to access Elasticsearch. When I stop the other process the error stops. The process may be using JDBC or some other driver that was provided before in 1.4.1 and is removed from the binary artifact in 2.0?????</p>