Adding MX Record to DNS

[anonim1]

I have a single-server implementation of Exchange server on a Windows 2003 machine. I can send e-mails to external hosts just fine, and I assume I can send and receive messages inside the domain as well. However, I cannot receive messages from external addresses.

I can telnet to the Exchange SMTP server from outside the network and send a message without any errors (forwarding port 25 through firewall). I also have the MX record set for my external IP address and host name through dyndns.org. However, I currently have no MX records on my internal DNS server, and I believe this is the problem.

Under Forward Lookup Zones, I have the following two Host (A) records:

(same as parent folder) Host(A) 192.168.0.3
exchange Host(A) 192.168.0.3

First, I think I need to add a record for my external DNS name, correct? Would I do this with an A record or a CNAME record? Would I set the IP address of this record to my internal or external IP address?

Second, I probably need to add an MX record. For the host or child domain, do I enter my internal or external DNS name? For FQDN of mail server, which A record do I need to select?

I will leave Mail server priority at 10, and I don't have any backup mail servers.

Please help me configure these settings...

 

[anonim1]

I've resolved the problem. Here is the solution for anyone interested:

Problem: cannot retrieve e-mails sent from external addresses.

Solution:
1. Create a new forward lookup zone on the DNS server comprised of your external domain name.
2. Add a Host(A) record, leave the Host field blank, and set the IP to the internal IP of your mail server.
3. Add a Mail Exchange(MX) record, leave the host or child domain blank, and select the A record you created in step 2 above to be the FQDN of your mail server.
4. ipconfig /flushdns and ipconfig /registerdns.

It should work after that!

 

[FAM]

anonim1,

Just to confirm, when you created your forward lookup zone did you add it as a,
Primary Zone>
to all domain controllers in the Active Directory domain xxxx>
and Allow only secure dynamic updates?

Cheers,
FAM

 

[anonim1]

FAM,

That is exactly how I set it up. Keep in mind that secure updates are only enabled if your DNS zones are AD-integrated.

Good luck.