title: Different AMI based on AWS Region?
body: <p>Is there any reasons that AWS AMI are different based on the region?<br>
  For example, if I try to launch an EC2 instance in Frankfurt I Got this AMI:</p>
  
  <pre><code>Amazon Linux AMI 2015.03 (HVM), SSD Volume Type - *ami-a8221fb5*
  </code></pre>
  
  <p>While in Oregon:</p>
  
  <pre><code>Amazon Linux AMI 2015.03 (HVM), SSD Volume Type - *ami-e7527ed7*
  </code></pre>
  
  <p>Note the different ami-version: <strong><code>ami-a8221fb5</code></strong> and <strong><code>ami-e7527ed7</code></strong>.<br>
  Is there any reasons?   </p>
  
  <p>And how can I build a cloudformation template that I can launch on both Frankfurt or Oregon without having to change the ami ?</p>