Yesterday, I'm minding my own business on Fedora Core 4, when my net connection suddenly dies. I check the usual suspects, but my DSL modem is working fine, my Linksys WRT54G Router is working fine, and I can still use my net connection on my other computers. I unplug and plug back in my ethernet cable from both the back of my computer and the router. Still nada. I don't really understand why something should go wrong, since I'm on a wired connection and everything had been working smoothly before. Furthermore, I hadn't done anything at all to mess with my settings.

According to ifconfig, my network interface was up and running perfectly. I deactivated and reactivated the network interface, even restarted the computer, but nothing changed - ifconfig said everything was fine, but I still couldn't do anything, not even ping the router. (Destination Host Unreachable)

One thing I did notice, however, were the LEDs on the back of my computer. I use the built in nforce3 networking on my ABIT motherboard. The LEDs were acting very odd; when I connected the network cable, the one on the top was a solid red, and the bottom one would blink orange sporadically.

I thought that perhaps, the cable I had only recently bought had malfunctioned. It goes under the house, so I thought that perhaps something had chewed the cable (even though mice and rats are virtually unknown in our area). So I installed an ethernet card I had laying around, a crappy Realtek. Oddly enough, with this card, I could ping my router, and even access it's web interface. So, it would appear that my cable is intact. I still, could not, however, access the outside internet. This is perhaps the most frustrating part.

I use the nameserver at 4.2.2.6. When pinging from my computer using the newly installed network card, I would get nothing but Destination Host Unreachable. When I logged on to my router's web interface and used the ping interface on it, it could ping 4.2.2.6 perfectly.

Whiskey Tango Foxtrot!

I thought that perhaps it was a Fedora Core 4 problem, but Debian had the smae problems.

If anybody has any help for me on this, I would greatly appreciate it.

Couple of questions coming your way.

1) Does your WRT54G have stock firmware or a third-party firmware? (OpenWRT, Sveasoft, HyperWRT, etc)
2) Are you using DHCP or manually assigning addresses to your boxes?

IT seems like that your Realtek should be able to see the outside world. The problem you are describing sounds like you've manually configured your network config manually using ifconfig. If you can ping your router and other boxes, then you don't have a gateway set to see outside. Try setting a default route.

Then try pinging your outside world (www.yahoo.com) or accessing your external nameserver.

Try this, let me know what you find.
-James

1) My WRT54G has stock firmware.

2) I'm manually assigning addresses to my box. This setup has worked for over a year, so it's kind of odd that it would stop working.

Debian all of a sudden could use my Realtek card, So I'm on the net using that for now. It works fine.

Still, it's kind of odd that the Nvidia onboard network just died. Again, when I plug in the cable, the top light solid red, and the bottom one blinks orange every so often. The only thing I can conclude is that the onboard networking just died. It's only a month-old motherboard too! I thought ABIT would do better than this.

I agree that is interesting that your onboard would act like that... and I wouldn't be able to make an informed suggestion regarding your nic card since I'm not sure what the indicator lights usually blink.

I'm glad that you're able to get online now thought.

A suguestion for you, if you're open to it. I used to use a WRT54G as my main accesspoint/gateway to the internet, and also assign static IP's to each computer. However, I found it much easier to assign static IP's using DHCP and MAC address assigning. A WRT54G can easily do this with a modified firmware (OpenWRT or Sveasoft). There are plent of arguments against Sveasoft for said GPL issues, but if you're still working on honing your Linux skills, then openwrt might be the way to go... (I used this until I was able to actually setup dedicated boxes) to do Static DHCP addressing, VPN tunneling (PPTP/IPSec server), and a whole slew of fun things. Just a thought (www.openwrt.org)

Either way, I would be interested to know if you were able to find out a reason as to why your realtek card wasn't accessing outside resources.