I just installed Kubuntu 12.04 on a new computer with an Asus motherboard containing onboard NIC. The onboard NIC is enabled in BIOS. I don't happen to have a spare network card to test with. The internet connection is via a D-Link router, either wired or wireless via T-Link USB wireless adapter. The internet connection works fine for other computers on the network (2 wired and 1 wireless). I have tried multiple known-good cables and router ports with this computer. I also booting into Kubuntu 11.10 LiveCD to test there as well, same results.

This machine will not connect to the internet. On the wired connection in 12.04:

shelly@neptune:~$ sudo service networking status

networking stop/waiting

shelly@neptune:~$ sudo service networking restart

stop: Unknown instance:

networking stop/waiting

shelly@neptune:~$ ping google.com

ping: unknown host google.com

shelly@neptune:~$ ping 127.0.0.1

PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.

64 bytes from 127.0.0.1: icmp_req=1 ttl=64 time=0.027 ms

64 bytes from 127.0.0.1: icmp_req=2 ttl=64 time=0.019 ms

64 bytes from 127.0.0.1: icmp_req=3 ttl=64 time=0.017 ms

64 bytes from 127.0.0.1: icmp_req=4 ttl=64 time=0.027 ms

64 bytes from 127.0.0.1: icmp_req=5 ttl=64 time=0.018 ms

64 bytes from 127.0.0.1: icmp_req=6 ttl=64 time=0.021 ms

64 bytes from 127.0.0.1: icmp_req=7 ttl=64 time=0.019 ms

^C

--- 127.0.0.1 ping statistics ---

7 packets transmitted, 7 received, 0% packet loss, time 5997ms

rtt min/avg/max/mdev = 0.017/0.021/0.027/0.004 ms

shelly@neptune:~$ ifconfig

eth0      Link encap:Ethernet  HWaddr 54:04:a6:82:6b:eb

          inet6 addr: fe80::5604:a6ff:fe82:6beb/64 Scope:Link

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:6 errors:0 dropped:0 overruns:0 frame:0

          TX packets:230 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000

          RX bytes:360 (360.0 B)  TX bytes:50506 (50.5 KB)

          Interrupt:46 Base address:0xe000



lo        Link encap:Local Loopback

          inet addr:127.0.0.1  Mask:255.0.0.0

          inet6 addr: ::1/128 Scope:Host

          UP LOOPBACK RUNNING  MTU:16436  Metric:1

          RX packets:134 errors:0 dropped:0 overruns:0 frame:0

          TX packets:134 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:0

          RX bytes:10616 (10.6 KB)  TX bytes:10616 (10.6 KB)



shelly@neptune:~$ lshw -C network

WARNING: you should run this program as super-user.

  *-network

       description: Ethernet interface

       product: RTL8111/8168B PCI Express Gigabit Ethernet controller

       vendor: Realtek Semiconductor Co., Ltd.

       physical id: 0

       bus info: pci@0000:04:00.0

       logical name: eth0

       version: 06

       serial: 54:04:a6:82:6b:eb

       size: 100Mbit/s

       capacity: 1Gbit/s

       width: 64 bits

       clock: 33MHz

       capabilities: bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation

       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full firmware=rtl8168e-3_0.0.4 03/27/12 latency=0 multicast=yes port=MII speed=100Mbit/s

       resources: irq:46 ioport:e000(size=256) memory:d0004000-d0004fff memory:d0000000-d0003fff

WARNING: output may be incomplete or inaccurate, you should run this program as super-user.

shelly@neptune:~$ sudo lshw -C network

  *-network

       description: Ethernet interface

       product: RTL8111/8168B PCI Express Gigabit Ethernet controller

       vendor: Realtek Semiconductor Co., Ltd.

       physical id: 0

       bus info: pci@0000:04:00.0

       logical name: eth0

       version: 06

       serial: 54:04:a6:82:6b:eb

       size: 100Mbit/s

       capacity: 1Gbit/s

       width: 64 bits

       clock: 33MHz

       capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation

       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full firmware=rtl8168e-3_0.0.4 03/27/12 latency=0 link=yes multicast=yes port=MII speed=100Mbit/s

       resources: irq:46 ioport:e000(size=256) memory:d0004000-d0004fff memory:d0000000-d0003fff

shelly@neptune:~$ sudo service network-manager status

network-manager start/running, process 823

shelly@neptune:~$ sudo service network-manager restart

network-manager stop/waiting

network-manager start/running, process 1684

shelly@neptune:~$ lsmod | grep -i r8169

r8169                  62099  0

shelly@neptune:~$

EDIT: It turns out that instead of the detected r8169 LAN card, this motherboard uses an 8111E as discovered here. So that is the solution.