Reverse DNS on SMTP Virtual Server

[rtiv]

Got a question:

I just checked off the flag to perform "reverse DNS lookups" on the SMTP server of my front end box. After further research, I pulled this sentence from MS:

"If Exchange Server can't verify the IP and DNS information, Exchange modifies the message header so that the key word "inverified" is inserted on the Received line of the message header"

To me, it sounds as if the message is still passed through ? I can't have that happen.....how do I make it so it drops the messasge ?

 

[FilthPig]

Unfortunately, Exchange 2000 doesn't do that. We looked for a 3rd party application to do that for us, and ended up creating a Linux mail gateway (sendmail) that performs that function. Marc Creviere

 

[rtiv]

Thanks. Does anyone know of a 3rd party product that will perform reverse dns lookups for incoming SMTP mail and IF the mail clients IP address fails to match the domain and host submitted in the SMTP session, it will DROP the SMTP session and forbid the piece of mail from passing through the gateway ???

Thanks

 

[Xybertron]

Have you tested to see if Exchange really fails the test? Dan
Microsoft Exchange Support @ Microsoft

 

[rtiv]

Hi Dan,

Actually, I've just received input from multiple sources that it doesn't work. I'd love to test it, but I'm not sure how ? Any suggestions ?

 

[tom11011]

I think the best exchange can do by itself is to filter email without a sender, filter email by email address, and to filter email by entire domain.

 

[The2ndOmen]

If you want to test it you can use outlook express to spoof a phony address and send the email to a valid exchange account and see if it goes through. Make sure the email domain you choose really doesn't exist.

 

[Comptek4]

You should try the GFI products. They have every thing for exchange you could ask for.

Http://www.gfi.com