title: "Virtualization type 'hvm' required" error in Apache Brooklyn
body: <p>I tried to create blueprint from chef  as per the link <a href="https://brooklyn.incubator.apache.org/v/latest/yaml/chef/creating-blueprints.html" rel="nofollow">https://brooklyn.incubator.apache.org/v/latest/yaml/chef/creating-blueprints.html</a> . </p>
  
  <p>The location and provisioning.properties for a large instance is provided through yaml. </p>
  
  <p>But when I launch it , I get the following error: </p>
  
  <pre><code>Required entity not healthy: ChefEntityImpl{id=aL3U028F}Failure running task invoking
  start[locations] on 1 node (Aw2cyO4I): Error invoking start at ChefEntityImpl{id=aL3U028F}:
  org.jclouds.aws.AWSResponseException: request POST https://ec2.us-west-1.amazonaws.com/
   HTTP/1.1 failed with code 400, error: AWSError{requestId='27baa951-42d1-424d-9bca-c97047207ac3',
  requestToken='null', code='InvalidParameterCombination', message=**'Virtualization type
  'hvm' is required for instances of type 't2.small'.',** 
  </code></pre>
  
  <p>Brooklyn is picking up t2.small type of instance ignoring the provisioning.properties mentioned through yaml .</p>
  
  <p>Is there a way to specify provision.properties via brooklyn.properties file  or force Brooklyn to override with the configuration provided via blueprint ?</p>
  
  <p>Can somebody help me with this ?</p>