Yes Cyril,
i have a modem wifi Netgear attached to the port 1 and a Dlink 10/100/1000 attached to the port 2.
Attached to Dlink are the other Macs. Everything was fine till my old Netgear 834gt died.
So i've purchased the new one who seems introducing that problem.
If i disconnect the ethernet port 1 (attached to the wifi modem) all is going fine.
in the Ethernet configuration you have an Advance / hardware : how it is set on the 2 ethernet port ?
Basic Settings with 10.0.etc address
(thx)