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 From:  "Lee Sharp" <leesharp at hal dash pc dot org>
 To:  <m0n0wall at lists dot m0n0 dot ch>
 Subject:  Re: [m0n0wall] DNS not forwarding
 Date:  Tue, 24 Jan 2006 20:25:26 -0600
From: "Jack Pivac" <email at delphinus dot co dot nz>
> Lee Sharp wrote:

>> Did you try the "net stop" above?  I know it seems wrong, but did you 
>> make sure?  Another way is to try "nslookup" and see if changing DNS 
>> within nslookup works.  When you change DNS in the IP properties, it 
>> flushes the DNS cache, and I think that is what's actually fixing it. 
>> And if you have a occasional problem that breaks the cache on one windows 
>> machine, it will also do it to others.

> Yeah I did try that, and also tried changing DNS within nslookup with 
> 'server x.x.x.x'

And this did not fix (even temporarily) the problem?  Then try pointing the 
m0n0wall DNS manually at and and overriding the ones 
provided by DHCP.  This will insure that your m0n0wall is getting a good 

> Do you know _why_ it breaks it on other computers as well? i'm curious....

This one is easy.  The DNS cache in Windows is about as stable as my 
ex-girlfriend.  If a lookup fails, it falls over to the secondary.  It will 
never fall back to primary unless the secondary fails.  If you get a 
corrupted lookup, it will stay in the cache.  If you get a failed lookup 
back from your DNS server, it will STAY failed in the cache, unless there is 
a flush or a timeout.  In general, when my internet connection is poor, the 
first thing I do is turn off the DNS cache.  It just saves headaches.


NOTE: and are 2 big DNS clusters in the US. (UUnet and 
GTE)  A quick tracert will tell you if they are close to you.  If not, try 
and find authoritative DNS servers for major backbones close to you, and use