Question : Reverse DNS woes and Exchange Server

I setup Exchange Server 2003 about 2 weeks ago along with GFI Mail Essentials as spam protection.

My DNS is hosted with Rackspace who I have my web server with.  For these purposes I'll use the name, domain.com

The Name Servers for domain.com are pointing over to Rackspace's domains.  From there I setup a new A record (exch.domain.com) which points to the Static IP of my exchange server.  The A record for domain.com points to my rackspace server.

The Domain name for our internal network is domain.local, I've setup aliases to accept the domain.com emails along with the appropriate users.

Problem comes in where I setup the reverse DNS on my Static IP provider as domain.com.  Recently I've been getting some bounce backs on email with spam related issues.   Problem is that I'm slowly getting blacklisted on a few spam sites because the reverse dns on domain.com doesn't match the IP address I'm sending the mail from (domain.local)

I've just tried changing the reverse dns on the static IP to  servername.domain.local but since the .local is not a top level domain I don't know how that's going to work.  It hasn't propagated yet to test.

Any suggestions?  I don't know how easy / feasible it would be to change the entire office domain name from domain.local to domain.com, but I'd feel that there would be a different way to do this.

Answer : Reverse DNS woes and Exchange Server

Is you Exchange server in rackspace also.

Generally speaking you have to speak to the ISP providing the line about changing reverse DNS records and not the Domain holder, so who's providing your connectivity? Most ISPs will change the reverse DNS address if an IP if you ask them to (BT is one exception I know of). It's the usual procedure of find the department responsible and find the email address or fax number they like to receive requests on. Changes to reverse DNS addresses are usually immediate rather than a 24 hour wait.

The reverse DNS should match the forward dns so if you have exch.domain.com as your forward lookup you should request the same for the reverse also. Don't just ask for domain.com.

I typically also change what my exchange servers respond as so they don't respond as internalservername.domain.local but the external domain name as this helps prevent spam rejections and means you can leave your internal domain on domain.local. To do this go to the SMTP virtual server (Not the SMTP connector) in Exchange system manager and select the "Delivery" tab on the right in the properties. Then click the advanced button bottom right and change the fully qualified domain name to read your external DNS name (exch.domain.com)

www.dnsreport.com is a good place to check out if you've been sucessful although it doesn't mind if you reverse DNS matches your forward, just that a reverse address exists.

If you want to go the whole hog, once you've done that use the instructions here to stop your server identifying itself as MS Exchange.

http://www.petri.co.il/change_the_smtp_banner.htm

I use method 1 as it's easier. The command actually look like this (as long as you only have 1 SMTP connector)
cscript adsutil.vbs set smtpsvc/1/connectresponse " "