Greetings everyone!

I Seem to have a pretty complicated problem here that I have been trying to figure out for the past 4 hours.

All of a sudden without rhyme or reason, My Lucid Lynx install stopped connecting to my network. This was without any intervention from me as I did not modify install or change anything prior to this happening.

What I have gathered so far is that upon initial boot eth0 seems to always be disabled. So I ifconfig eth0 up to bring it back online. All the settings in the network applet seem to be intact for my manual network that has DHCP disabled. Let me re-iterate that these settings worked fine for months then all of a sudden something went belly up. The same machine will connect fine with the same settings from within Win7.

ifconfig command shows both eth0 and the loopback interface but eth0 never manages to secure the 192.168.1.3 address that it should have. ping 192.168.1.1 returns "Network unreachable" so it appears the connection is being cut off at the machine and not the router. I did check to make sure the connection was even recognized and it sees the wired connection going to the router, but nothing else.

/etc/network/interfaces only shows two lines regarding the loopback interface and nothing else; eth0 seems non-existant within this file which I find odd.

Well guys, where to start?

You haven't supplied much information. Such as if you have a wired interface or a wireless interface. Do you use DHCP to assign the IP address, or do you have a static configuration. What device does your computer use?

Seriously? If I was on a wireless connection I would be using iwconfig and I stated right in my post I was using a manual network with DHCP disabled.

I didn't exactly fix it, but I did find a workaround. I re-enabled DHCP in the router and appended /etc/network/interfaces.

After that I used my temporary connection to install wicd. I've read the stock networking Appleton can be a real pain sometimes.

I agree that since Ubuntu is very good for beginners, the fact that working on iventing things for doing life easier for these, these newest inventions can become hard for someone that, though even experienced, doesn't think the low-level part (ifconfig and related) has changed the minimum.

The summary that I had to face several years ago when I started using ubuntu, is that it uses network manager to handle connections, that since of course ifconfig is used, the service is not /etc/init.d/networking, but "networkmanager". And the UI for this has improved so I haven't found bugs in the last year, and by clicking/right clicking the icon on the task bar, you can enable/disable the interface, edit the configuration, etc. So, by knowing this, currently it's safe enough to rely on the UI, taking that you don't want complicated things, or things that can be done in a one-time setup.