title: What does errno=13 mean when connecting via OpenVPN?
body: <p>The tail-end of an OpenVPN connection (that otherwise appears successful) says (with leading timestamps omitted):</p>
  
  <p>Note: Cannot open TUN/TAP dev /dev/net/tun: Permission denied (errno=13)<br>
  Note: Attempting fallback to kernel 2.2 TUN/TAP interface<br>
  Cannot allocate TUN/TAP dev dynamically<br>
  Exiting</p>
  
  <p>What is the problem here?</p>