Ubuntu 10.10 LAN connection stopped working...

Linux and Unix-Like Ubuntu
1

Well this is weird. I restarted my dual boot Win7/Ubuntu 10.10 from ubuntu to windows. Everything was working fine and windows is always connecting properly to my lan. After restarting back into Ubuntu, all of a sudden I can't connect to my network. It looks as if its trying to connect through ipv6, which this network is not. I used someones advice on how to disable the ipv6 cause whenever I do ifconfig on my ubuntu it gives the following:

Sorry I can't write the whole thing but but its too long to copy it over from that computer. You can see that it addresses ipv6 still. I even have it disabled in network preferences.

I don't know what is going on!

Any help would be appreciated.

Thanks

2

That ipv6 stuff is always there, it doesn't mean its actually working.

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3

Oh okay...

Any ideas on how to check where the problem is coming from. I mean Windows has no problem connecting on the same computer so i know it's not a hardware or cable issue. Ubuntu was working fine up until days ago. The only thing that could affect it was that I installed a fresh version of the system recently. However, it worked fine for days since the reinstall.

Thanks,

4

Any suspicious entries in dmesg, /var/log/messages or /var/log/daemon.log?

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5

Daemon logs are a little strange. I was looking at them and the one that was zipped and rotated by the system has info about networking until April 24th. The next one that was rotated but not zipped yet has something saying:

I don't really know how to identify problems that good as of yet in the logs so if you can tell me what to look for it would be beneficial.

Thanks

6

Servus,

Please start the following command in a separate console:

$ sudo tail -f /var/log/daemon.log

Then activate the network interface.

Could you please paste the output seen in the console?

TIA, Lo�c

7

Sorry silly question,

How do I activate the network interface?

---------- Post updated at 04:30 PM ---------- Previous update was at 04:24 PM ----------

Sorry figured it out,

Apologies

One second to transfer log output...

---------- Post updated at 04:48 PM ---------- Previous update was at 04:30 PM ----------

Here it is. I had to stop the interface and then I restarted it:

8

AFAICS, dhcp seems to work as you obtain the IP address 10.70.29.178 from our server 10.70.31.252.

I am a bit surprised however that - once NetworkManager obtains the IP - it does not continue with the registration. Is there perhaps a few more entries after May 2 16:29:29 (ideally, until NetworkManager says that the IP failed)?

Another thought: Could you check the configuration for the interface eth0:

  • right click on the NetworkManager icon (that shows the network connection)
  • edit connection
  • select eth0
  • select Edit...
  • go to the tab IPv4 Settings. Make sure that the method selected is DHCP
  • go to the tab IPv6 Settings. Make sure that the method selected is ignore
  • eventually save your changes "Apply..."

Lo�c

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9

Yeah,

That part is done correctly. I am now logged in as root and still the same problem. I have repeated the procedure and it looks that at the end of the process dhclient has permission problems. I have highlighted it and another failed flag in red.

Any more ideas?

Thanks

10

That it's trying to create a file in /usr/local is very bizzare. Have you installed any software that you built by hand?

11

Hey Corona.

Nope. That was bizarre. I'm not that experienced with Ubuntu but that was a little strange to me.

12

hmm... That's true, /usr/local is strange.

  • If /var symlinked to /usr/local/var?
  • Can you access the /usr/local/var/lib/dhcp3/ directory? If so, perhaps an apparmor issue?
13

/usr/local/var/lib/dhcp3/ doesn't exist.

/usr/local/var/lib/NetworkManager does though...

---------- Post updated at 12:23 PM ---------- Previous update was at 12:18 PM ----------

I've actually found some more info on those errors, and it seems to be an apparmor bug that was affecting the previous Distros. Also there seems to be a buggy issue with dhclient-script which I've tried to work on with suggestions from other forums and nothing seems to work.

I think I'm going to reinstall the system and try the new 11.04...

14

Just fun for, you may want to create the dhcp3 directory (with appropriate access right) under /usr/local/var/lib/dhcp3/ and check if that's do it.

drwxr-xr-x   2 root          root          12288 2011-05-02 21:59 dhcp3

I have 10.04 and the dhcp3 directory for lease is located under /var/lib/dhcp3. If that directory also exists on your system, a symlink for /usr/local/... might do it also.

If you can afford it, a fresh install might be the way to go to ensure a "clean system".

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15

Yeah thats what I did and It works perfectly now. Something broke and was causing problems. Don't know but since I need this computer to work, I have reinstalled system and now have 11.04. It works perfectly.

16

Glad that you solve the problem :wink: Sometimes, it's better to (re)start from scratch...

Cheers, Lo�c

1 Like