Ubuntu Ethernet Unplugged?

Ahoy! This is my first post here on Tek Syndicate, but I have been a member for some time now.

Google has failed me :( I have been looking for a fix for my Ubuntu 14.04 Ethernet. It says that its unplugged even though it is actually plugged in. I'm fairly new to Linux and I'm taking every opportunity I can get to learn more. I have tried a few different "Fixes" on the internet, but sadly I still cannot get it to work.

Any pointers to the rookie here?

I'm assuming your NIC is off, check from the network settings (right-click the net icon) if it's enabled or not
EDIT: Or via the terminal 'sudo ip link set eth0 up'

could not find device "eth0" also tried eth1

What does the output look like when you enter:

ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DORMANT group default qlen 1000
    link/ether 00:23:15:61:49:d8 brd ff:ff:ff:ff:ff:ff
4: wmx0: <NO-CARRIER,NOARP,UP> mtu 1400 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 20
    link/ether 64:d4:da:10:e9:87 brd ff:ff:ff:ff:ff:ff

I'm guessing that wmx0 is your ethernet device and you can see it's reported as being down. Try

ip link set wmx0 up

I hope that works, because I'm not really a linux expert either. Let me know how it went :)

EDIT: fixed the command

wmx0 should be a WiMax device. Do you have usb WiMax adapter plugged in?
Also, what does the following command tell you?

ifconfig -a
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:65536  Metric:1
          RX packets:164771 errors:0 dropped:0 overruns:0 frame:0
          TX packets:164771 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1604220266 (1.6 GB)  TX bytes:1604220266 (1.6 GB)

wlan0     Link encap:Ethernet  HWaddr 00:23:15:61:49:d8  
          inet addr:192.168.1.155  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::223:15ff:fe61:49d8/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:445050 errors:0 dropped:2 overruns:0 frame:0
          TX packets:325701 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:297239912 (297.2 MB)  TX bytes:98354325 (98.3 MB)

wmx0      Link encap:Ethernet  HWaddr 64:d4:da:10:e9:87  
          UP NOARP  MTU:1400  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:20 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

and no, i do not have a usb wimax adapter

This is very weird...
Do you know what network card the machine has?
Also, what does this tell you:

lspci | grep -i ethernet

It should list all detected ethernet controllers.

Nothing comes up when I add that. It just returns to where you can add commands to the terminal. To be quite honest i'm not sure what kind of card it is. Its on an Asus u52f

Just to make sure is your network card enable in your bios (intel maybe) hoping it's not dead

Since nothing came up, the operating system has never detected the network card. Do you know if the card works in WIndows? Also, have a look in the bios to check if the card is disabled somehow.

Otherwise it seems the card is broken...

For reference, this is what I get when I type lspci | grep -i ethernet
00:19.0 Ethernet controller: Intel Corporation 82579LM Gigabit Network Connection (rev 04)

1 Like

I'll have to take a look when I get home. Thank you though for the help gentlemen

The ASUS website suggests your have an Authos Ethernet controller
As @Zeverin suggests to confirm:

lspci -vv | grep Ethernet

or

lspci -vv | grep Atheros

If that's the case that its Atheros you can try modprobe alx or modprobe atl1c depending on the controller. See here for more info http://www.linuxfoundation.org/collaborate/workgroups/networking/alx

Nothing comes up when I use those commands. It just goes back to where I can enter something new into the terminal.

Unless youve done something horribly wrong with the ubuntu install (unlikely) or turned off the ethernet card (far more likely) then its simply broken.

Either that or thinking about it... you are using sudo to run these commands? maybe ubuntu wont give you anything back without being root.

Try

sudo lspci -vv | grep Ethernet

to check its actually working running sudo lspci with no other arguments should spill out all your pci info.