If you’re using an OpenVPN Server to surf in Ubuntu, maybe you experienced this strange problem : you can connect but you cannot surf !    This how to fix it...

Before we start check your current IP online and save it.

The first thing you have to know is that you shouldn’t use NetworkManager Applet to configure your OpenVPN Connexion, it seems that there’s a problem with vpn connections when using this applet (atleast with Intrepid), you can connect but traffic isn’t redirected correctly, so let’s first make sure you’re correctly  connected ! The best thing to do is to download the configuration files from the OpenVPN Server’s website (just look in the forum if you don’t find it, it’s generally an archive file with a *.conf file and a *.crt file, this last one is the certificate) and use’em directly in a shell console.

Copy the archive content files to

/etc/openvpn/

Type :

cd /etc/openvpn && sudo openvpn yourserver.conf

Enter your login and password and wait till you see :

Initialization Sequence Completed

It means that you’re in.

Now to make sure that you’re not facing a routing problem, just type :

route -n

If you see tunX connections with new IPs, it’s OK you’re connected, if one of your web connected peripheral connections (ethX, athX…) is showing the IP of your OpenVPN Server as a destination you’re correctly routed.

Now try to ping the tunX IP with a gateway, if you’ve got this message :

ping: sendmsg: Operation not permitted

You got the fix ! It’s a SIMPLE FIREWALL PROBLEM !

To solve it, you have to edit :

/etc/firestarter/user-pre

First thing to do is to make it writable (it’s a read-only file) then paste these lines and save the file :

# Allow OpenVPN traffic
$IPT -A INPUT -i tun+ -j ACCEPT
$IPT -A OUTPUT -o tun+ -j ACCEPT

Restart Firestarter :

sudo /etc/init.d/firestarter restart

It should work now ! Just re-check your Online IP to see if it changed !