I have shared my internet connection via Ethernet with another computer, using the shared option under Ethernet in Network settings. I believe this is working but I can't know for sure as I am unable to access Computer 2, because I don't have a monitor for it.
Router ‒‒‒‒‒‒‒‒‒‒> Computer 1 (Ubuntu) ‒‒‒‒‒‒‒‒‒‒> Computer 2 (Other Linux)
So the first question is: how do I find out the IP of Computer 2 so I can SSH to it from Computer 1.
And: how can I forward a port right through from my router to the machine using the shared connection (computer 2).