Why do trunk Ports have to be set to auto for Speed and duplex? I have a 4006 going to 2960 and 3550 if I set the ports to 100, full the link remains down, if set to auto link comes up (config on both sides)? Also, a I have core switch that is the VTP server 4510 connected to the 4006. If I connect an access switch to the 4006 the VTP info does not get picked up (automatically, if configured it does). If I directly connect to the 4510 it does automatically, why is this?