title: What would cause intermittent EC2 > RDS host resolution issues?
body: <p>The issue is an inability to resolve the DB host but it's not persistent. </p>
  
  <p>Environment:</p>
  
  <p>AWS EC2 Ubuntu 16.04</p>
  
  <p>connecting to:</p>
  
  <p>MYSQL 5.7 RDS</p>
  
  <p>This started just after an upgrade from Ubuntu 14.04 to 16.04.
  It works probably 99/100 tries, but then fails and throws this exception: <code>An exception occurred in driver: SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo failed: Name or service not known</code>. </p>