Re: Terminal Server - Restricting Internet Access
Hi Ian87, and welcome to Ubuntu forums.
Note that normally moderators will close old threads with new posts added, and a couple of others around this one were closed for that reason. Perhaps this one was left because, the iptables rules stuff has not changed. Anyway...
That iptables rule will not work for your application. It would only work on the same computer where the packet originates. Owner information does not go over the wire.
As for what to do for your case, it depends: If your Ubuntu server is also your router/gateway to/from the internet then it would be fairly easy to deny internet access for your local computers (but perhaps a little more difficult to learn iptables in general); If you are using a hardware type router/gateway device, then it would depend on the router.
Any follow-up information on your issue would be appreciated. Please have the courtesy to report back.