This might sound like a stupid question, but are you sure the ethernet connection is not working? The only reason I ask is I ran into a similar(ish) issue myself where my receiver complained it wasn't connected to the internet when in reality it was. When I tried to download plugins the receiver would just give a message "no internet connection", so I ssh''d into the receiver and verified the internet connection was working from the cli. I guess if your ethernet really is down you won't be able to ssh (or telnet) into the box, if this is the case then feel free to ignore me

When you click on "download plugins" the openvix software tests for a working internet connection by opening a tcp connection to 8.8.8.8 on port 53. In my environment this won't work as I redirect any traffic on my internal networks destined to google public DNS to my own DNS resolvers. The ACL's on my resolvers wouldn't allow a connection from my receiver so the internet check always failed.

This probably isn't your issue, but I just thought I'd mention it.