Problem: you have a BSD box, like a m0n0wall and you need to force the ethernet media type. There’s no convenient GUI to do it.
Solution: get a command prompt (like /exec.php on m0n0wall) and do:
ifconfig $ADAPTER media $SPEED mediaopt $DUPLEX
ifconfig xl0 media 100baseTX mediaopt full-duplex
The actual syntax varies slightly on some drivers, so Google for ‘bsd man $DRIVERNAME’, e.g. xl.
Photo: View from the cheap seats at Dartmouth Women’s Basketball
For m0n0wall, see the FAQ on hidden config.xml options for an easier way. Just running it from exec.php won’t survive a reboot.
Also as a warning – always be careful forcing speed and duplex – most people cause more problems than they solve doing this. If you’re going to force, it has to be done on both the interface and the switch port, but the vast majority of the time autonegotiation works fine and you should leave well enough alone. I see far more problems with duplex mismatches in environments that try to force things because they end up doing it inconsistently.