title: Cassandra null pointer and no information in logs
body: <p>I've installed cassandra 2.0. But then I am starting it using <code>sudo service cassandra start</code> it crashes. Only thing which appears in the <code>cassandra.log</code> is <code>Error: Exception thrown by the agent : java.lang.NullPointerException</code>. </p>
  
  <p>How does it possible to understand what is going on there? All what I remember that I've changed some path <code>JAVA_HOME</code> in alternatives not sure if it causes a problem.</p>
  
  <p>I am on:
  Centos 6
  java -version 1.7
  Cassandra 2.0</p>