Hi
I'm new here, hello everyone

I've got a question relating to VPN. There seem to be many threads asking how to setup iptables to allow traffic through VPN but I could not find one asking my question.

I often connect to open wireless access points at airports etc. I have an iptables firewall setup on my netbook and connect using OpenVPN. I also have a VPN connection on my Android phone for similar reasons.

What I would like, particularly on the phone is to prevent applications from connecting to the internet other than via the VPN server. In this way, if I become disconnected from the VPN (or I become disconnected from wireless and then reconnected without VPN) my private data will not be sent over an unsecured wireless network.

So is this possible with an iptables rule or similar?

Thank you.

Can you set your default route to the VPN end point when you are connected?

Thank you for the reply Stickman.

I'm no routing expert, but if I did that would it be able to work out the rest of the route (after the VPN server) itself?

Also, how would I set the end point? Can you give me a couple of words as a starter?

Thanks again.

In most cases the route would point to the VPN IP address of the VPN server. The key words that you're looking for are "route" and "add".

You should be able to add statements to your OpenVPN config at home to push your home default route to your remote laptop/phone. When the VPN connection is set up, the push should replace the default route on your laptop with the default route to your home network. You should also push the home network DNS server addresses to your laptop/phone. You shouldn't need to monkey with IPTables at all.

You'll need a directive in the host config file along with the push route commands,

push "redirect-gateway".

This should force your remotes to use your VPN connection for all IP traffic.

The config file for your remotes should have the keyword "client" in it to enable the client to pull config data from the host.

Check the OpenVPN "HOW-TO" for more detailed information on host and remote config file directives..