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Reverse MX Lookup
How do I set this up?

 11:59 pm on Sep 19, 2002 (gmt 0)

I found a small ISP that will not deliver my mail unless they can verify that my email address exists. I've found the edit (A) records, (MX) records & (CNAME)settings. I'm pretty sure this has something to do with the MX, but I'm not sure what to put in the three boxes to get my email address listed. Here are the boxes to create a new MX record.

MX Hostname:

The only MX record in the system now is:




 12:15 am on Sep 20, 2002 (gmt 0)

Hostname is the domain you registered domain.tld. In the absence of a MX record your mail would be handled by the maschine that name points to. With an MX record you can specify that your mail should be handled by a different maschine. When there is more than one MX record remote mail servers will contact the one with with the lowest preference. If that fails they will try the one with the next-heigher one.

So the MX record present will cause your mail to be delivered to mail.domain.com instead of domain.com.

Hope this helps



 12:20 am on Sep 20, 2002 (gmt 0)

Thanks for the reply. Maybe I didn't explain my problem right, sorry. Some ISP's try to verify that an email address exist BEFORE they will accept the mail for delivery. In other words, they check an email from john@doe.com to see if it's a valid email address. This is done with some kind of reverse lookup to doe.com. If my domain was doe.com, how to I tell my domain to tell other ISP's that john is a vaid email address within my domain.


 12:32 am on Sep 20, 2002 (gmt 0)

You would need to set the MX record to the maschine running the MTA for your domain and ensure that your MTA allows the SMTP VRFY command.


 12:44 am on Sep 20, 2002 (gmt 0)

Thanks! That's what I needed to know...


 2:45 pm on Sep 20, 2002 (gmt 0)

The reverse record should be all you need tying your IP back to your domain name. I don't know how it is done but I just had to have it done for a new IP / Domain.

For the paranoid (like me) SMTP VRFY should be disabled for security reasons. It opens a door that can be used to probe for user names and mail lists.

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