Problem with some domains and some domain resolved

[Stephane Bortzmeyer]

On Tue, Jul 10, 2007 at 05:29:58PM +0300,
 Nayeem <nayeem at ksa.zajil.com> wrote 
 a message of 63 lines which said:

> Is it really  DNS problem or network problem.

I do not know but I can send a few free advices.
 
>  [root at ns1 named]# nslookup

Use dig to debug, nslookup is deprecated and brings its own problems.
 
> > www.cnn.com
> 
> Server:         127.0.0.1
> 
> Address:        127.0.0.1#53
> 
>  
> 
> ** server can't find www.cnn.com: SERVFAIL

What software does 127.0.0.1 run? BIND, of course, but which one? Can
you go to CNN's name servers directly:

dig @twdns-01.ns.aol.com. ANY cnn.com

If no, use ping and traceroute to see if it is a network problem.
 
> > www.google.com
> 
> ;; connection timed out; no servers could be reached

Same question.
 
> So please tell  me where to trace this problem.

1) Read the BIND log. This is mandatory.

2) [Much more difficult] Run tcpdump on the name server. Something
like 'tcpdump -n port 53'.