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[Geoff Austin]

Hi,

I recently set up a couple of DNS servers and had them registered for my 
domain. I use these dns servers to resolve domain addresses and they 
work perfectly. At least half the people I know are able to resolve 
addresses for my domain without problems, the other half cannot. I have 
noticed that those who cannot, MAY, fall into a category, which would be 
  users of large ISPs as they use British Telecom, SwissCom  and Equant. 
However, this may be a red herring.

At one stage Swisscom could not resolve the web server, but was happy 
receiving and sending email. For a few days it worked OK and now it 
cannot resolve any address and mail does not work.

I have fiddled with the DNS settings a number of times and am getting 
nowhere. I have run reports from www.dnsreport.com and similar from 
www.ipplus.net and they seem to be happy with the dns. I could really 
use some help from an expert.

I'm running bind 9.2.2-p3 on fedora.
The domain name is w-sys.co.uk
The ip addresses of the two dns servers are:
82.68.177.91 and 82.68.177.92
Examples of a DNS servers than cannot resolve are:
  ns1.bt.net
  ns1.ip-plus.net
Examples that can are:
   212.23.3.11 and
   212.23.6.35

My intention was to have just two boxes in the DMZ, one a primary dns 
that does only dns (91), and one which is the secondary dns, a web 
server, a mail server and an ftp server(92). These are both set up as 
masters as I was playing with external and internal views of the domain, 
which seems to work from where I'm sitting.

I'm sure it's just a simple newbie problem, any pointers on how I might 
investigate further, would be much appreciated.

Many Thanks,

Geoff Austin