01 Jul 2013

OVPN normally defaults to UDP. This might be better for real-time
applications where all clients and servers are "close" However, if you
want your VPN to work 'everywhere', choose TCP.

  • Some firewalls (ahem, juniper) don't seem to like UDP packets and you won't be able to connect if you use them.<
  • Using UDP over the Internet is likely to have problem due to packet loss

Using TCP with OVPN, all these problems go away. I learned this the
hard way. Enjoy!