title: ec2 security group settings, sftp and port 80 settings
body: <p>I have a Linux based ec2 instance on aws with prepackaged Tomcat7 and so far I'm able to:
  ssh into the instance from command line,
  connect to the instance FileZilla,
  sudo start/stop tomcat (tomcat is listening on port 80)
  All development administration on the project happens on Ubuntu 10.10</p>
  
  <p>Problems/questions are:</p>
  
  <p><strong>FileZilla</strong>: when I try upload a war file to webapps I get:</p>
  
  <pre><code>Error: /opt/tomcat7/webapps/my-fancy-app-0.1.war: open for write: permission denied
  Error: File transfer failed
  </code></pre>
  
  <p>I've not added any users ( or ec2-user to be exact ) to any groups associated with Tomcat.</p>
  
  <p><strong>Port 80</strong>: how do enable outside access on port 80? 
  I have just the default security group, have not added any custom settings. When I select HTTP from the 'Create a new rule' dropdown the default setting is 0.0.0.0/0 - is this the safe or correct setting? When I have Tomcat running with that rule applied and try to visit the url shown next Public DNS I get (503 error I believe): <code>Service Temporarily Unavailable
  </code></p>
  
  <p>Last but not least, what is an Elastic IP and what role does it play in the larger picture?</p>
  
  <p>Any help whatsoever will be extremely appreciated. Hopefully I'll get through this and be able to put all this in a 'paint by numbers' kinda tutorial. </p>