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Cincinnatux
May 7th, 2012, 07:59 PM
I do not know with certainty that my problem is related to the upgrade; the only other possibility is that my mobo's Realtek ethernet hardware has gone bad.

The ethernet connection worked fine for a few days after the upgrade from 11.10, but I've read elsewhere of other users experiencing wonky wireless problems that took time to kick in after an upgrade, and there were no changes to the hardware coincident with the loss of ethernet communication.

I have already manually installed the current driver from Realtek and ensured that it is not competing with an incorrect Realtek driver (apparently this is a common explanation for the problem I've encountered).

'lspci -nn', among other things, returned:

05:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 03)

'sudo nm-tool' resulted in:

sudo: nm-tool: command not found

'lsmod | grep r8' returned:

r8168 215626 0

Is Network Manager borked? If so, how do I fix it without an Internet connection?

If there is a thread out there I should be reading instead of pestering you fine people, I'd be grateful for a reference. What I've been able to find thus far has not helped, though it did provide me with the commands I used above. Sorry if my typing is a bit off; I'm borrowing my wife's computer and she hates it when I switch her keyboard from QWERTY to Dvorak, so it's all hunt and peck for me.....

FWIW, I'm running 64-bit Precise Pangolin on my computer. I tried using 12.04 install USB to restore ethernet function by simply reinstalling everything, but it could not establish Internet connectivity during install, so I aborted the install.

Help? Thanks!

praseodym
May 7th, 2012, 09:31 PM
Please show

cat /etc/network/interfaces
cat /etc/resolv.conf
ifconfig -a

Cincinnatux
May 8th, 2012, 03:25 AM
Please show

Thanks for the quick reply!
/etc/network/interfaces shows only the following two lines uncommented:


auto lo
iface lo inet loopback

There are no uncommented lines in /etc/resolv.conf; the commented lines are as follows:

Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN

ifconfig -a returns:

eth0 Link encap:Ethernet HWaddr 00:24:1d:7e:4f:63
BROADCAST MULTICAST MTU:1500 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:1000
RX bytes:0 (0.0 B)
Interrupt:45 Base address:0x2000

The file repeats this information for eth1, changing only the HWadd from :63 to :72, the Interrupt from 45 to 46, and the Base address from 0x2000 to 0x4000. The lo information in resolv.conf looks as follows:


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:18764 errors:0 dropped:0 overruns:0 frame:0
TX packets:18764 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1523568 (1.5 MB) TX bytes:1523568 (1.5 MB)

Should I be able to understand these files? I feel a bit simpleminded; I've been running Ubuntu as my primary OS (I no longer even dual-boot) since Feisty Fawn (after spending 15 years of frustration with DOS and Windows) and I still look at this stuff and scratch my head.... Anyway, thanks for taking the time; I hope this thread proves useful to others.

Cincinnatux
May 8th, 2012, 04:26 PM
As an update, I have confirmed a hardware failure: the Westell A90 wireless modem (supplied by my ISP) still supports WiFi, but all of its Ethernet ports are non-functioning. My wife's computer (a Win7 machine) and my XBOX can both connect to the Internet wirelessly through the A90, but relying on direct Ethernet cable connections results in failure for both machines. I am hoping to get the modem replaced today, and will report back on whether that fixes anything.

praseodym
May 8th, 2012, 08:45 PM
Try internet connection sharing via the Win-machine. I dont know if you need a cross-cable for it?!

Cincinnatux
May 8th, 2012, 09:43 PM
As an update, I have confirmed a hardware failure: the Westell A90 wireless modem (supplied by my ISP) still supports WiFi, but all of its Ethernet ports are non-functioning. My wife's computer (a Win7 machine) and my XBOX can both connect to the Internet wirelessly through the A90, but relying on direct Ethernet cable connections results in failure for both machines. I am hoping to get the modem replaced today, and will report back on whether that fixes anything.

Well, I can confirm that replacing the modem does nothing to restore Ethernet capability to my Ubuntu box. The XBOX is able to use the Ethernet again, though. I guess that's something.

Cincinnatux
May 8th, 2012, 09:45 PM
Try internet connection sharing via the Win-machine. I dont know if you need a cross-cable for it?!

Assuming I could do this, what then? This would be, at best, a temporary solution, as the two computers are not normally near each other.

Cincinnatux
May 8th, 2012, 10:53 PM
I was able to get the Ethernet during recovery mode, but lacked the know-how to use that to restore Ethernet function in my desktop. So I'm now in the process of reinstalling 12.04 from scratch. Surely, if I'm looking at a software problem, this will either fix it or simplify my troubleshooting a bit (since I had originally used the 'upgrade' function to go from Oneiric to Precise, and I know that there is a greater risk of things going funky during such upgrades and it is possible that a clean install will do the trick here).

I wish I could take a more sophisticated approach to my problem, but I have not learned enough Linux troubleshooting to do that. I will post an update after I have time to finish the install and check everything.

Chilongola
May 8th, 2012, 11:14 PM
I had this problem with Ubuntu 12:04 so, I moved to Linux Mint - same thing, then onto Xubuntu 12:04 again same thing. Live cd works in each case. In all cases problem started after first update.

By the way I have a "wired" connection

Cincinnatux
May 9th, 2012, 03:45 AM
I had this problem with Ubuntu 12:04 so, I moved to Linux Mint - same thing, then onto Xubuntu 12:04 again same thing. Live cd works in each case. In all cases problem started after first update.

By the way I have a "wired" connection

I wish I had useful advice for you. I got around the problem by reinstalling 12.04. So far, so good. Still no clue what hacked it all up in the first place.

For the record, with my fresh install, I now get:


~$ lspci -nn | grep Ethernet
05:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 03)
06:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 03)



~$ sudo nm-tool
[sudo] password for m:

NetworkManager Tool

State: connected (global)

- Device: eth1 [Wired connection 2] -------------------------------------------
Type: Wired
Driver: r8169
State: connected
Default: yes
HW Address: 00:24:1D:7E:4F:72

Capabilities:
Carrier Detect: yes
Speed: 100 Mb/s

Wired Properties
Carrier: on

IPv4 Settings:
Address: 192.168.200.30
Prefix: 24 (255.255.255.0)
Gateway: 192.168.200.1

DNS: 192.168.200.1


- Device: eth0 -----------------------------------------------------------------
Type: Wired
Driver: r8169
State: unavailable
Default: no
HW Address: 00:24:1D:7E:4F:63

Capabilities:
Carrier Detect: yes

Wired Properties
Carrier: off

:~$ lsmod | grep r8
r8169 62099 0
As I understand it, this means that I'm not actually using the correct driver for my Ethernet card, but it works for now. Should I have problems, I will likely start by uninstalling the r8169 driver and install the r8168 driver to match my r8168 hardware.

~$ cat /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth1
#NetworkManager#iface eth1 inet dhcp

~$ ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:24:1d:7e:4f:63
UP BROADCAST MULTICAST MTU:1500 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:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:45 Base address:0x2000

eth1 Link encap:Ethernet HWaddr 00:24:1d:7e:4f:72
inet addr:192.168.200.30 Bcast:192.168.200.255 Mask:255.255.255.0
inet6 addr: fe80::224:1dff:fe7e:4f72/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:4613 errors:0 dropped:0 overruns:0 frame:0
TX packets:2082 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3398810 (3.3 MB) TX bytes:280021 (280.0 KB)
Interrupt:46 Base address:0x4000

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:128 errors:0 dropped:0 overruns:0 frame:0
TX packets:128 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:12874 (12.8 KB) TX bytes:12874 (12.8 KB)

Now I'm off to restore my preferred settings. Here's hoping I don't screw anything up.... :)

Chilongola
May 9th, 2012, 06:01 AM
What do you know!! After two days of not using my PC I just turned it on and all is okay. I am typing this from it right now. Guess it just wanted to "cool down"

Cheers guys.