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How to verify internet configuration.

Posted on 2006-04-18
Medium Priority
Last Modified: 2010-03-19

the situation was, our email was hosted on a third party, that also manage our DNS.

we install on our network a exchange 2003 server. we ask our host to change the DNS to point the mx record directly to our network.

here is the infrastructure :

INTERNET   ---   FIREWALL  ----  EXCHANGE 2003 Front (DMZ) --- FIREWALL ( SAME ) ---  EXCHANGE 2003.

here is what happen, for outside person, we do not receive everything, we receive yahoo.com, we don't receive sympatico.com,
we can send to everybody.

I check the firewall for spaming, it's off.  AntiVirus is off,  In exchange, DNS check is not selected on both server.

what I suspect is that our host did not modify properly the dns and is relaying the message.  

so I whant to verify our DNS over the internet to check for the MX record.

how can I achive that ?

Question by:Martin_Dalpe

Accepted Solution

The_IT_Garage earned 1000 total points
ID: 16477881

Expert Comment

ID: 16477928
You can also use NSLOOKUP from the command line to check this.  The easiest thing is to have several people you know who are in geographically disperse areas, and who have different ISPs use NSLOOKUP to determine what they're seeing for your MX record.  If this isn't an option, you can use NSLOOKUP locally and change your default server so that you're using someone else's DNS Server for the lookup...unfortunately, many ISPs are restricting the use of their DNS Servers to clients in their IP Spaces.  There are still a few DNS Servers out there you can use...you just have to do some trial and error to find them.

Syntax for NSLOOKUP can be found here:


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