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After upgrading to 12.04 my interent connection no longer works. More precisely it is really, really, slow, and occasionally will connect, but do so only for a few moments and then disappear again. I am on a Lenovo Workstation e20.

Output of ifconfig:

eth0 Link encap:Ethernet HWaddr 70:f3:95:00:64:3e
inet addr: Bcast: Mask: inet6 addr: fe80::72f3:95ff:fe00:643e/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:7398 errors:0 dropped:74 overruns:0 frame:0 TX packets:6684 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:5407828 (5.4 MB) TX bytes:854343 (854.3 KB) Interrupt:20 Memory:fb120000-fb140000

lo Link encap:Local Loopback
inet addr: Mask: inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:1587 errors:0 dropped:0 overruns:0 frame:0 TX packets:1587 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:152089 (152.0 KB) TX bytes:152089 (152.0 KB)

I am really at a loss for what to do. I am relatively new to Ubuntu, searched the other user questions and couldn't figure this out.

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I had this problem not to long ago... turned out it was the network cable... Not sure how or why... but maybe something you might want to consider looking into... – TheXed May 2 '12 at 13:25
Not a cable problem, checked the hardware. Laptop works fine when connected to the cable. – Dave May 2 '12 at 15:31
Okay, I just wanted to throw that out there... – TheXed May 2 '12 at 15:39
Welcome to Ask Ubuntu! We need more hardware information to help you, can you look at this question and then edit your question adding the information. – Jorge Castro May 2 '12 at 20:26
It is a Lenovo e20 Workstation. When I get home I'll run the terminal commands to get the required info and update. In the meantime I know it is using the e1000e driver (as I started to looking into that to see if that was the problem). – Dave May 3 '12 at 22:30

I encountered the same problem after upgrading to 12.04 LTS.

The following solution worked for me.

Open this file in a text editor as root:


(One way to do that is gksu gedit /etc/network/interfaces.)

Add these lines to the file:

auto eth0
iface eth0 inet dhcp

Save the file and quit the text editor.

Now restart the network:

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Try this : Press Ctrl+Alt+T and then enter this in the command prompt :

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

After that, retry connecting

. It should connect then.... :)

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protected by Community Nov 6 '12 at 21:03

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