I have seen this once before but I have just seen it happen twice in one of our classrooms and I am confused.
Each student had a console connection to their router. The router was then connected to a switch via the gig port. When the students brought up putty and selected 'serial' the output was from the switch. If I disconnected the connection between the switch and the router both putty connections froze.
Through a cobination of rebooting/recabling the output then came from the router.
How? Why?