My computer is connected to the school's network via an Ethernet cable, but ubuntu won't recognize the network. It will scan the network for about 30 seconds and then a small error window pops up saying "Network disconnected, You are now offline".

I have been trying to fix the issue for almost 3 days now; I even re-installed Ubuntu from my bootable USB. This was a scratch install of Ubuntu 12.04 LTS via a bootable usb (which was created on my Macbook pro after I converted the .iso to a .img file) on a new computer that I just recently built. I already contacted my school's IT department, and my MAC address is registered with them. However, I am the only student running linux on the entire campus and they are unable to give me further support. I have researched the forums extensively and have tried various solutions, but none seem to work. I was advised by the IT department to leave my internet connection for IPv4 on automatic DHCP, rather than setting it to manual and copying the information from my laptop. Additionally I tried using a friends USB wireless adapter (a Netgear Wireless N-300), but Ubuntu didn't recognize the device as a wireless adapter. As a result, wireless does not appear to be a viable backup solution.

When my IPv4 is set to automatic (as recommended by my IT department) my terminal ifconfig is

Eth0 Link encamp:Ethernet  HWaddr 74:d4:45:0d:bc:b5

     inet6 addr: fe80:76d4:35ff:fe0d:bcb5/64 Scope:Link

     UP BROADCAST RUNNING MULTICAST MTU:1500 METRIC:1

     RX packets:389 errors:0 dropped:0 overruns:0 frame:0

     TX packets:0 errors:0 dropped:47 overruns:0 carrier:0

     collisions:0 txqueuelen:1000

     RX bytes:39214 (39.2 KB)  TX bytes:0 (0.0 B)

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:16 errors:0 dropped:0 overruns:0 frame:0

     TX packets 16 errors:0 dropped:0 overruns:0 carrier:0

     collisions:0 txqueuelen:0

     RX bytes:1312 (1.3 KB)  TX bytes: 1312 (1.3 KB)

When my IPv4 is set to manual and is copied from my MacBook Pro's internet configuration, my ifconfig is:

will@Anarch:~$ ifconfig

eth0      Link encap:Ethernet  HWaddr 74:d4:35:0d:bc:b5  

      inet addr:138.234.212.246  Bcast:138.234.223.255  Mask:255.255.240.0

      inet6 addr: fe80::76d4:35ff:fe0d:bcb5/64 Scope:Link

      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

      RX packets:22060 errors:0 dropped:0 overruns:0 frame:0

      TX packets:7 errors:0 dropped:3371 overruns:0 carrier:0

      collisions:0 txqueuelen:1000 

      RX bytes:2659497 (2.6 MB)  TX bytes:461 (461.0 B)



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:4597 errors:0 dropped:0 overruns:0 frame:0

      TX packets:4597 errors:0 dropped:0 overruns:0 carrier:0

      collisions:0 txqueuelen:0 

      RX bytes:404944 (404.9 KB)  TX bytes:404944 (404.9 KB)

As seen in the comments below this question, here are the results for the ipshow command when IPv4 is set to automatic:

ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 74:d4:35:0d:bc:b5 brd ff:ff:ff:ff:ff:ff

Here is my nm-tool for the automatic IPv4 setup:

will@Anarch:~$ nm-tool



NetworkManager Tool



State: connecting



- Device: eth0  [Wired connection 2] -------------------------------------------

  Type:              Wired

  Driver:            r8169

  State:             connecting (getting IP configuration)

  Default:           no

  HW Address:        74:D4:35:0D:BC:B5



  Capabilities:

    Carrier Detect:  yes

    Speed:           100 Mb/s



  Wired Properties

    Carrier:         on

Here is my nm-tool for the manual IPv4 configuration:

will@Anarch:~$ nm-tool



NetworkManager Tool



State: connected (global)



- Device: eth0  [Wired connection 1] -------------------------------------------

  Type:              Wired

  Driver:            r8169

  State:             connected

  Default:           yes

  HW Address:        74:D4:35:0D:BC:B5



  Capabilities:

    Carrier Detect:  yes

    Speed:           100 Mb/s



  Wired Properties

    Carrier:         on



  IPv4 Settings:

    Address:         138.234.212.246

    Prefix:          20 (255.255.240.0)

    Gateway:         138.234.208.1



    DNS:             138.234.4.54

    DNS:             138.234.196.47

    DNS:             138.234.4.158

This is the Ping to google's server (Ip: 8.8.8.8) using Manual network settings:

will@Anarch:~$ ping 8.8.8.8

PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.

From 138.234.212.246 icmp_seq=1 Destination Host Unreachable

From 138.234.212.246 icmp_seq=2 Destination Host Unreachable

From 138.234.212.246 icmp_seq=3 Destination Host Unreachable

From 138.234.212.246 icmp_seq=4 Destination Host Unreachable

From 138.234.212.246 icmp_seq=5 Destination Host Unreachable

Here is a short list of failed solutions that I have already tried from other forum posts:

• manually setting up my IPv4 based off of the information from my laptop's (A MacBook Pro) network connections


• registering my MAC address with the campus


• Resetting the ethernet by turning the card off and on in the Bios setup


• Deleting and creating the network connection in the Network Connection’s window


• Using echo on | sudo tee /sys/class/net/eth0/device/power/control


• And other's that I can't call to mind at the moment

I'm done with classes for the day, so if anyone needs any more information please let me know. I will continue to troubleshoot for the rest of the day, so any help is greatly appreciated.

P.S. Would it be advisable to try to install a different distro of Linux and see if it can connect to the network?

Thank you,
William