I was under the impression that reverse DNS was only used to check that the sending server was who it said it was however my colleage believes that MX records are also used to determine if the e-mail domain is valid for the sending host. Can anyone confirm if this is the case?
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Do reverse DNS lookups use MX records?
- Thread starter snella
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Both Sender Policy Framework & Sender ID use MX record information. I believe that DomainKeys probably also does, but I have NOT really used it.
Oops, I didn't finish that thought.....
So there are several ways to verify the sending host. Different mail servers use different methods. By itself, reverse DNS only does what you've stated: verify that the sending server name matches it's IP address.
So there are several ways to verify the sending host. Different mail servers use different methods. By itself, reverse DNS only does what you've stated: verify that the sending server name matches it's IP address.
Most mail servers use a reverse-dns lookup to validate that an email server really is who it says it is because the name and IP information presented during the handshake can be spoofed (faked). Doing a reverse DNS lookup before allowing an email server to send your server email helps to cut down on the amount of spam you'll get.
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