I would have preferred that my Android 1.6 device supported OpenVPN out of the box. Unfortunately, this is only available for rooted devices and a bit of suffering. Instead, I went for configuring IPsec inside L2TP VPN server. All of it stuffed into an old and low-end Soekris net4511 board running Voyage Linux.

First, I will just redirect you to the well-documented, lengthy but primary resource:

Using a Linux L2TP/IPsec VPN server

On the client side, this post is quite complete:

Adding VPN connections to Android 1.6 (Donut)

If you’re feeling impatient and brave, perhaps you’ll succeed with the configuration files that follow (they worked for me)… since those are highly dependant on your network setup, YMMV, a lot.

Before jumping right into the meat and to avoid confusion, let’s see what is the game all these evil daemons are going to play:

1. A client (my android phone), connects to the server on port 4500.
2. IPsec server (OpenSWAN) responds and asks for the PSK.
3. If the previous “gatekeeper” is ok with you, control is handed over L2TP, the other “tunnel keeper” who will ask for another password.
4. If L2TP is satisfied with your answer, PPPD, the ancient UNIX beast will be waken up and ask for… your user and password !
5. Congrats ! You’re survived the gates, now you’re on your home network from your smartphone, ain’t it cool ?

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