AmesMUG: MacBook not seeing Ethernet

[David Faden]

Hallo,

I'm studying abroad this semester in Dortmund, Germany, and am having
some trouble getting my MacBook to work with the Ethernet jack in my
dorm room. In fact, even when the cable is plugged in between the
computer and the jack, according to the Network panel, "The Ethernet
cable is not plugged in." The jack is restricted to work with only one
MAC address. However, I have confirmed with the system admin that the
address they have for me matches the address listed in the Network
panel.

I am able to connect to Ethernet with my computer using the same cable
in the library. (There however there are no restrictions on which
addresses may connect.) So, the cable seems to be all right.

We also used the same cable to successfully connect a different
computer to the jack in my room. So, the jack is not dead.

I also had trouble connecting my computer to a home LAN and to the
campus network at the George Mason Uni campus but had no problems at
ISU. The home LAN apparently had no restrictions on which MAC
addresses could connect (but the owner is a little unsure about this).

Any ideas on the source of the problem? The sys admin suggested that
perhaps the MacBook is sending out packets with a different address
than that listed in preferences, but I'm not sure how to snoop on this
info. I haven't had much luck with my Internet searches.

Thanks much. Tschuess!

David