> At the moment anything going to any other server goes through the VPN,
> but not stuff directly to the server.

Right - so I imagine that means you have a default route on
the client which goes out on the vpn interface to your server.

Use "/sbin/route -n" to check that - look for the line with a "G" in
its flags, and a interface device name which matches the vpn. If that
isn't the case maybe posting the output here could help us understand things
better.

To get to the server via the encrypted link, find the IP which
appears in the gateway column of the line mentioned above - it
should be on the same subnet as your outgoing vpn (so encrypted)
ip of your client, and use that. That IP should also be
discoverable on the server if you go ifconfig there and look
for the vpn interface.

TL;DR: Use the VPN ip of the server, not its normal one. Edit
/etc/hosts on the client, if you'd like to use a name.

regards

marc