Ubuntu 12.04 64-bit will not connect to wired network

Question

This is a brand new 64-bit PC, built around a Gigabyte Z777-D3H Motherboard and an i7 processor. It has 2x1Tb SATA drives, one loaded with Windows 8 and the other with Ubuntu 12.04.

The wired network connection into my Belkin F1P1241ENau modem works with no problem at all, and a test install of Ubuntu 12.04 into a Virtual Box client also connects with no problem, but the installation on the dedicated 1Tb HDD will not connect. The messages I get are "Network Disconnected - you are now offline" and "No Network devices available"

I also tried connecting via a wireless USB dongle (which I know works fine) with no better results.

My old Dell 32-bit computer runs Ubuntu 10.04 and has no trouble connecting with the same cable and DSL modem.

Any help at all will be greatly appreciated.

Answer 1

This situation is symptomatic of a missing driver. The Ubuntu-via-VirtualBox installation has the advantage of passing through Windows drivers before it ever touches the hardware.

Your new motherboard uses an Atheros GbE LAN chip, which is relatively new and may take a while to receive full kernel support out of the box. UbuntuForums has a nice post about two options for installing drivers.

The post will take you to the newer of the driver options, with details at http://ubuntuforums.org/showthread.php?p=12206393.

From that post, you can see how to manually get the needed driver:

sudo apt-get install linux-headers-generic build-essential
wget http://www.orbit-lab.org/kernel/compat-wireless-3-stable/v3.5/compat-wireless-3.5.1-1-snpc.tar.bz2
tar -xf compat-wireless-3.5.1-1-snpc.tar.bz2
cd compat-wireless-3.5.1-1-snpc
./scripts/driver-select alx
make
sudo make install
sudo modprobe alx

If you have a WiFi USB dongle, you can use it to connect to the Internet for the wget step. If not, download that file from another computer, and transfer it on a flash drive. The latter link above has more info for dealing with lack of Internet connection.