Re: [gentoo-user] DNS lookup fails on a server; no changes since it worked

["A. Khattri" <ajai@bway.net>]

On Sun, 20 Nov 2005, Micah R Ledbetter wrote:

> I have a server out on the net, and it's been up for a week or two.
> I've been on and off it all week long, but as of last night, DNS
> didn't seem to work for it. Network connectivity worked, because not
> only could I ssh *in*, but I could also contact the outside network
> as long as I used something in the hosts file or an IP address.
> Adding more (known good) DNS servers to /etc/resolv.conf doesn't seem
> to help. DNS was working recently, and I haven't changed anything
> since then. A reboot didn't help (I would have just stopped &&
> started networking... but, well, all I have is ssh, so...).
>
> One very weird thing is that it can apparently send mail to outside
> network addresses. It could send to my gmail account fine last night,
> though it seemed to take a while (20 minutes or so, when normally
> it's instantaneous). I don't have gmail or google in my /etc/hosts.
>
> I've seen elsewhere to look at the output of iptables, but it has
> never been installed.
> The contents of /etc/nsswitch.conf are at http://vlack.com/vlack/lol/
> nsswitch.conf. I'm getting nowhere, and I have no idea why.

What is /etc/resolv.conf?

Are you running a local name server or uses someone else's?

If you are using someone else's can you ping them?

If you can ping them, install bind-tools and see if you can run direct
queries against them with dig or host, something like:

dig @xxx.xxx.xxx.xxx -t mx gentoo.org

where xxx.xxx.xxx.xxx is the IP of the DNS server you are checking.

Lots of troubleshooting options here.



-- 

-- 
gentoo-user@gentoo.org mailing list