Hi, I ran into a strange problem today. At work I have 2 PCs on a KVM switch. One windows and a centos 5.3 box. Both are connected to an ADSL service but the windows box is logged into the company VPN most of the time. The centos box comes in useful as I can get to sites the company doesn't like

Anyway, today started the same as usual but later I noticed that the centos box was having problems with gmail. I tried to navigate to another site and that is the last internet site I have visited on that box! Whenever I start up firefox I can see "looking up www.linuxquestions.org" and then the "address not found"/"page load error" screen.

So a few simple checks - ethernet cable is okay. I have a samba server running on this box so can I access a share from the windows box? Yes. I can ping from windows to linux and linux to windows okay.

The only thing I can not do is access the internet which was working this morning. I tried changing the network settings - no proxy, auto detect proxy. There is no proxy server but nothing changed.

So, firefox is stuffed. But the network is active.

Any ideas on how to troubleshoot this one?

You haven't given any details about your network setup, so this is just general troubleshooting info: check your routing table to make sure you have the correct default route in there, check your dns settings and make sure you have access to your dns servers, check your firewall to make sure that nothing has changed and is now blocking ports, check your ethernet info to look for inconsistencies, check the ip number and mask.... Can you ping the router/gateway? Has anything changed there?

Embarrassment. I reset the router and all was well again. I'll just slip out the back door while noone is looking

Happens to the best of us! Glad it's sorted now.