TomatoUSB

It would be really nice if it was possible to set up a pptp client (ms vpn) via a GUI.
Is it possible at the moment to do this via ssh shell?

It depends on your WAN connection type.

If you use DHCP, just select PPTP instead, mark "Use DHCP" box, and configure your VPN PPTP account info and any additional options.
That works starting from build 51.
Tested with my DHCP WAN and several private VPNs.

Hi teddy_b,

Thanks for the quick response! It worked like a charm! Any idea what would happen if the remote end is not available?

Mhhh.. it then only routes all traffic over the vpn. I only want to route the traffic for that subnet.

Yep, it does.

If you want something different, maybe you can solve it by custom static routes?

I've been trying that but I think I know too little of how routes work to make that happen. You can't replace the default route with the gui.
So then I rebooted and recreated the /tmp/ppp directory. But then when I run pppd it doesn't connect and throws this error:
LCP: timeout sending Config-Requests

You can't replace the default gateway via GUI, but after establishing PPTP connection I believe you should have 2 default gateways - one for each interface (ppp0 and vlanX)… - Never mind, it doesn't create the second default gateway. You can add one manually on Advanced->Routing page, but it may not solve your problem.

Anyway, there's always an option to start pppd manually with custom config. You need to create /tmp/ppp/options file with configuration parameters, and /tmp/ppp/pap-secrets and /tmp/ppp/chap-secrets files with usrename/password. You can see the sample files by configuring PPTP connection via GUI - these files will be created automatically. Then start pppd.

Thanks for all the help!

I wrote down all the files and contents (http://paste.ubuntu.com/507789/) but I think I forget a file somewhere. Because if I start pppd it doesn't connect. It just timeouts. Well, I'll have another look this evening. Maybe I missed something obvious.

I've installed an openvpn server on the remote end. That was the easiest solution :)
I've got one problem though: vpn_client1_nat isn't saved in nvram. It's empy after every reboot. It's not 0/1 but really empty. If I set it to 1 from the commandline on the router and refresh the interface it's ok. Then, when I do a commit it's removed again.

Do you know what the problem could be?

What nvram usage is displayed on the "Administration->Configuration" page?