Ok, so at our organisation we have an external web proxy run by our local county, with proxy settings distributed via GPO, the problem is with BYOD on the rise we're having trouble with certain devices that either can't take proxy settings or don't handle exceptions well and redirect all traffic, including that meant for internal servers, out to the proxy.
Now, I have a tower with 2 network cards that was donated to us running Ubuntu, I've not played with linux as a routing tool before, but all i want it to do is direct all traffic to the external proxy, and add a list of exceptions that remain internal to the network, so i can point some of our devices at it as the default gateway and it can do the proxy decisions for them.
Thanks