Can't connect to the internet

[valok]

Ok, so I just got done installing Kubuntu for the first time. And for some reason I cannot connect to the internet. The network manager icon in the bottom right corner (when moused over) says that eth0 is unavailable.

So I went into the network connection area, created a new connection using dhcp and it still does nothing. It doesn't even look like its making an attempt to connect to my router. In fact, under the 'last used' tab it says 'never'.

I found a common bug that was solved by commenting out a line in /etc/dhcp3/dhclient.conf, and that didn't do anything either.

I'm not all too experienced with linux, so I'm not really sure what to do next. Please help!

Edit - When I run ifconfig it doesn't return an inet addr, netmask, or broadcast.

[Snowhog]

Re: Can't connect to the internet

First, you need to give information about what you have:

Version of Kubuntu you are using;
Version of KDE you are using;
Network card/chip in your PC;
Make and modle of your router.

[valok]

Re: Can't connect to the internet

Forgive me for asking, but how do I find out what network card I have?

For the rest

Kubuntu 9.04
KDE 4.2 (I think, should be whatever comes stock with 9.04)
And my router is a linksys WRT54GS

I think this might be my ethernet card info

[Snowhog]

Re: Can't connect to the internet

Open a console and type:

lspci | grep Ether

Copy and paste the result.

[valok]

Re: Can't connect to the internet

00:14.0 Bridge: nVidia Corporation MCP51 Ethernet Controller (rev a3)

[valok]

Re: Can't connect to the internet

I also just double checked my BIOS to make sure that the onboard LAN is enabled, and yea, it is. And I also made sure that it wasn't the ethernet cable by plugging my wife's laptop in via that cable, and it still works.

And I'm not sure if this is noteworthy, but I'm pretty sure that when I was running this computer on windows last week, a light would turn on in the back of the computer when it was plugged into the router. (the light was right next to or inside the ethernet jack). But now, there is no light.

[dibl]

Re: Can't connect to the internet

You are correct -- on recent vintage computers there is a LED indicator for ethernet activity. No light -- no ethernet.

You might want to verify that your router is still alive and functioning. I just replaced a 3 year-old WRT54G that died this Spring. One would think they would last longer .....

[valok]

Re: Can't connect to the internet

My router definitely is functioning in general. The computer I'm on now is connected to it via wireless, and it also was able to connect through a wired connection with the same cable my computer is attempting to use. So I think I've isolated the problem to something in my computer.

I don't think its a problem with the actual LAN chip though, because it was working on windows right before I installed Kubuntu.

If it helps, I also tried installing Arch linux, and had this same exact problem.

So the question is, what in the world would cause my computer to be able to recognize my ethernet card (as can be told by the fact that I got an output from lspci | grep Ether) but at the same time not turn the ethernet card on?

[valok]

Re: Can't connect to the internet

I also just noticed that the MAC address from ifconfig is not the same as on my router.

[valok]

Re: Can't connect to the internet

Well, I've found the problem (I think).

I tried installing Ubuntu 9.04 to see if that worked no luck

Installed windows, got internet there.

For ****s and giggles, I installed Ubuntu 8.04 and it worked!

So it appears to me that my problem is because of the new linux kernel and my ethernet card not agreeing with it. If anyone finds information regarding this and discovers a workaround or something of the like, please let me know.

[flarson]

Re: Can't connect to the internet

Wrong conclusion. Almost certainly the problem is the faulty network configuration in Kubunutu. Since lspci knows what card you are using, and eth0 is shown in ifconfig the linux kernel has support for your network card. All you have to do is configure it. As root, edit /etc/network/interfaces to look like this

auto lo eth0
iface lo inet loopback
iface eth0 inet dhcp

Then remove network-manager with

sudo aptitude purge network-manager

Then bring up the interface with

sudo ifup eth0

At that point you should be set. It is possible that network-manager will not unconfigure interfaces so that you may need to run

sudo ifconfig eth0 down

and then

sudo ifup eth0

After you get the network up, if you want a GUI tool install wicd.

[valok]

Re: Can't connect to the internet

Hmmm, I was having the same problem with both Ubuntu 9.04 and also with arch linux. The reason I thought it was the kernel was because it seemed to be the only common thread between those three OS's. But if that isn't the case, then what else do these 3 have in common that would cause the problem?

Thank you very much for this info! I'll give this all a shot when I get home and see what happens.

[flarson]

Re: Can't connect to the internet

There may be many things in common, but my guess would be KDE4, particularly the kde network-manager applet.

[eaterjolly]

Re: Can't connect to the internet

Open a console and type:

lspci | grep Ether

Copy and paste the result.

I did that too and got "bash: spci: command not found"

[Snowhog]

Re: Can't connect to the internet

eaterjolly@

"bash: spci: command not found" means you typed the command incorrectly. It's easier to 'copy and paste' so:

lspci | grep Ether

Copy and paste the above into the console. (For information, lspci is LSPCI (if it were in upper case) and the | between the commands is not a lower case L but the pipe symbol which is gotten with shift+\)