Beta version of a tutorial to get SmoothWall and different DD-WRT routers to interconnect via openVPN. Using smoothwall as a OpenVPN server, and Net-to-Net with the newest alpha. There are still some issues, but connection from LAN side behind DD-wrt to LAN side behind Smoothwall is working perfectly. But the other way around is not working quite as it should… more on that later!

1. Install Zerina

* Download latest version from http://www.openvpn.eu/zerina/?q=download
* Upload ZERINA-experimental.tar.gz.tar to your Smoothwall, untar and run ./setup. No spesical options.
* Login in to smoothwall for setting up Zerina OpenVPN.

2. Config Zerina OpenVPN.

* Set up Root/Host Certificates:
As describe in the setup, you only need to fill out:
Organization Name:
Smoothwall’s Hostname:
Country:

* Global Settings:
Enable OpenVPN on Red interface, and allow VPN access to Green.
The rest, default settings should be ok.

* Add Net-to-Net connection.
You don’t have a Zerina Net-to-Net client package, so lets create a Net-to-Net VPN.
Default settings should be all right, the only thing you need to fill out is:
Remote hostname or ip:
Remote LAN subnet:

Generate a certificate:
Fill out all required fields!

3. Creating Certificates for DD-WRT.

* Download HOST.p12 certificates you just created.
* Open DD-wrt and go to Services.asp.
* Enable OpenVPN
* Enter ip/hostname for your smoothwall
* Default values should work.
* Use certmk.sh to generate usable cert for dd-wrt. (certmk.sh is a linux bash script)
The output from certmk.sh will give you Cert that you should past into dd-wrt openVPN client config.

4. Finish and Start up…

* Start OpenVPN Services on your Smoothwall
* Reboot your DD-WRT unit
* That’s it!

5. Verifying / Troubelshooting

Checking if everything is working, try pinging. You can also check `route` on DD-WRT

You should then get something like this:
10.x.x.5 * 255.255.255.255 UH 0 0 0 tun0
10.x.x.1 10.0.10.5 255.255.255.255 UGH 0 0 0 tun0
10.0.1.0 10.0.10.5 255.255.255.224 UG 0 0 0 tun0

Where 10.x.x.x is your openvpn subnets and 10.0.1.0 is your LAN behind the smoothie…
Still not working, check log files on smoothie…..