Hello,
I am studying for CCNA R&S and I have a question that I cannot find the answer: I am reading the possible situations from show interfaces command line. And I read that if you have the situation Line Status Up and Protocol Status Down, it means "An interface up/down state is not expected on LAN switch interfaces. This indicates a Layer 2 problem on Layer 3 devices". To check this I put a router and a switch in Cisco Packet Tracer, and made a mismatch in duplex between both (it worked). And I started to think that if you configure duplex or speed, you are configuring how the bits are being transmited in the cable, so it should be a layer 1 problem. But what I read says that it is a layer 2 problem. So I cannot understand which layer correspond to this problem and why.
Thank you,
Franco Riggio
