First ... Here's a list of what I have at my disposal:
Desktop computer with built-in network adapter (Realtek RTL8111DL chipset) running 64-bit Ubuntu 10.10
Mobile broadband adapter Huawei E220 (though it identifies itself as 220/270?)
WLAN router (Linksys WRT54GL) that has been flashed with Tomato firmware 1.27vpn
Number of other stuff that happily interconnects using WLAN; phones, a few laptops etc.
I wish to share my "wireless broadband" connection (Indonesian prepaid Telkomsel Flash) in my desktop computer through WLAN/WiFi for other computers in my home (a couple of laptops and such). Furthermore, I have signed up for a VPN-account (not for the sake of security, but simply because Telkomsel's DNSs are more often offline or otherwise hindered and simply not working like they should) and would like to have all traffic routed through OpenVPN-tunnel.
I have tried different setups in an attempt to achieve this, but so far with not much success. I can connect to network with the desktop machine, and can manually open a VPN-tunnel, but sharing the connection (with or without VPN-tunneling) has proven to be an exercise in futility. I have found some examples of how things should
work, but most of the examples appear to be either outdated or, for some reason, overly complicated (which came as rather a surprise for me, since normally I've found that things with Ubuntu have been extreamely straight-forward) ... often both.
I would wish for the connection to open automatically (setting the "connect automatically" only works sometimes?) and - if possible - start the OpenVPN-tunnel as soon as connection has been established (I don't know why, but Network Manager's VPN setup's "connect automatically" appears to have no effect). Also, I would wish that if the connection gets dropped (seems to happen a lot more often on Ubuntu than for example my MacBook) it would rise again automatically (very often on Ubuntu, when the connection drops, Huawei is unable to connect again before I run through the motions of "disconnect/reconnect USB-cable").
On my opinion, doing all this should really be a piece of cake, but for some reason the solution has managed to avoid me for several days already. I'm counting on you, experts; help me out :)