Ethernet interface - checking the status
I have a question about how actually check if somebody plugged additional computer to a second interface on a PC.
My setup is like this: I have one PC with 2 eth interfaces, the first is serving as the connection to the internet and the second is to be used by the second computer. When the second computer is connected to the second interface it will be able to reach the internet., but that is not the main issue here.
On my PC I would like to check if somebody connected a computer to the second interface.
Is there any way to probe the kernel or something to see if something is connected to this interface or not?