at home I have the following setup where I do testing right now:
physical ethernet and wifi card @ 192.168.178.x subnet
the USB RNDIS EV3 card and a just installed loopback adapter.
Ev3 Brick is set to default 10.0.1.1 currently
I run Windows 7 and can reproduce the following:
When setting the RNDIS adapter to dhcp (default) it doesn't get an ip assinged from the brick. it defaults to the 169.254.x.x range that means no dhcp found.
with that setting I can not ping the brick.
When I set the RNDIS adapter manually to an IP of the 10.x.x.x range, like 10.0.1.22, I can ping both 10.0.1.22 and 10.0.1.1
You are right about the loopback adapter. It's not needed. It was before I realised that the brick and NDIS adapter use 2 different IPs and are not the same.
So basically the question remains why the RNDIS adapter doesn't get an IP assigned by the brick.
I made a vanilla install, no changes made.
I already tried changing the netadress file before. I set it to 192.168.178.222
The IP was correctly displayed in the brick LCD.
Manually putting the RNDIS in the same subnet, I was not able to ping the brick.
Maybe it was because the last part of the IP hat 3 digits. I will try again.
Edit: Interesting, I changed to IP 192.168.1.1 now and now even dhcp works.
Thanks again for the help!