In Part 4 we configured our Raspberry Pi router to maintain a number of OpenVPN tunnels and to route through them selectively. Now we'll look at the steps needed to allow connection to our LAN via OpenVPN. Although helpful, as the HomeHub doesn't provide VPN connectivity, this stage doesn't really count as Usurping the BTHomeHub.
The steps are almost completely identical to those performed when Installing Open VPN on Debian. We're going to have to NAT connections though, as the HomeHub is a little stupid and we can't add static routes to it (so if we're connected to the VPN and accessing the Internet, it won't know where to route the response packets).
What we'll do, though, is only NAT if the connection isn't to something on the LAN.