I have a following simple topology: Cisco2960[Fa0/1] <-> [eth0]server. eth0 is using e1000e(Intel(R) PRO/1000 Network Driver, version 1.4.4-k) module. Is it possible to bring eth0 down in a way that switch port Fa0/1 shows not-connected? I tried with "ip link set eth0 down" and "modprobe -rv e1000e", but the Fa0/1 is still up. One option would be to force eth0 to 1000BASE-T mode while switch port does not support this. In addition, it's possible to execute offline tests to eth0 interface with "ethtool -t eth0" command, which will bring interface down for few seconds. However, is there an option to bring interface permanently physically down?

Might be a way to use acpi. My thinking is that many boards have nic powered up even with system off. Bios may have setting for wol but doesn't usually power it down. The keep alive signal I think causing this. Somehow you have to power it down. An add on card may be easier to power off.

Pull the ethernet cable.

Log on to the switch and down that port.