Ok I got a wierd one that just started about 4 hours ago.

Any mozilla based product (thunderbird, firefox, epiphany, etc) has stopped resolving dns names.

Lynx, curl, ssh, dig... they all work.

If I switch firefox to a squid proxy server it works.

Type the address manually in the URL field and it works.

Just not a name like http://www.garagesaleorganizer.ca

Any ideas how to fix or debug this issue?

Mozilla products like to try ipv6 DNS first. In Firefox, go to "about:config" and set network.dns.disableIPv6 to "true".

That didn't work. Still can't get mozilla products working.

It was worth a shot. Do they not resolve any names? What does /etc/resolv.conf have?

I tried on three different networks... same thing. I have the problem on two computers. (both laptops)

Ping works no problem:

[mcarter@snow-faerie ~]$ ping www.garagesaleorganizer.ca
PING garagesaleorganizer.ca (65.39.182.97) 56(84) bytes of data.
64 bytes from mail (65.39.182.97): icmp_seq=1 ttl=52 time=73.0 ms
64 bytes from mail (65.39.182.97): icmp_seq=2 ttl=52 time=72.3 ms


In a web browser 65.39.182.97 works.. www.garagesaleorganizer.ca does not. If I try it in links, curl, or lynx they work. Just not mozilla products.

Thunderbird mail is the same way. mail.carterfamily.ca fails. but 65.39.182.97 works no problem.

Evolution works ok... just not thunderbird.

This one's really got me stumped. Also why did it just stop working. I checked yum logs and there was no updates. Nothing on the computer has changed... not to mention I had two go at the same time.

Really odd. Using any proxies? Check your Firefox settings to see if there are any proxies defined. If so, should they be?

With NO proxies the problem exists.

With a localhost:3128 proxy everything works fine (but squid is doing the resolving not firefox) Which is a work-a-round... but doesn't help me with my thunderbird problem.

I thought it might be Rogers.com doing some bit shaping but I tried a VPN to work, and an open wireless network in the area... they did the same thing.

Not to mention my server works find, and my daughters computer. It's just the laptops with a problem at the moment.

(and before you ask... I tried wireless and hardwired both the same)

FOUND IT!!!

There was a corrupt line in my /etc/hosts file.

I have a central hosts file which my computers refresh from every four hours. My daughter's computer and server hadn't polled from it yet.

Seems every other program in Linux just ignored it. firefox/thunderbird must have been erroring out or something.

At least the problem is fixed.

Thanks for your time.

No problem. What kind of line broke everything?