title: Updating IP addresses in Apache Ambari
body: <p>I am running an Ambari installation (1.7.0) on <a href="http://hortonworks.com/" rel="nofollow">HDP</a> (2.2.0.0-2041).  After rebooting one of the machines, the internal IP address changed.  This means that Ambari can't find it.  (We're running on AWS EC2, so the hostnames have the form ip-x-x-x-x.)</p>
  
  <p>How do I inform Ambari of the new ip address?  The only option I've found so far is to add a new host, but as I understand this will wipe the machine clean.</p>