Note: This is my re-post from Stackoverflow.
I've been messing with a test environment for security purposes where a DMZ RHEL5 sendmail
server is used as a relay for an
Exchange 2007
server.
Exchange is working in the environment, I have Vista and XP VMs using Outlook on the Domain to send e-mail to each other. I've been trying to simulate an external internet VM sending an e-mail to the DMZ sendmail relay, which forwards to the
Exchange server.
Before everyone thinks this is too big a problem/question, I've followed the sendmail/Exchange guides and all I want to know is how I can determine why a relayed message/e-mail in
Exchange is "Undelivered".
Basically I send a SMTP message to the sendmail
server, which relayed to my
Exchange. The /var/log/maillog shows the e-mail being relayed to
Exchange.
Nov 17 13:41:22 externalmailserver sendmail[9017]: pAHIfMuW009017: from=<
[email protected]>, size=1233, class=0, nrcpts=1, msgid=<
[email protected]>, proto=ESMTP, daemon=MTA, relay=[10.50.50.1]
Nov 17 13:42:17 externalmailserver sendmail[9050]: pAHIfMuW009017: to=<
[email protected]>, delay=00:00:55, xdelay=00:00:36, mailer=relay, pri=121233, relay=mailserver.xyz.local. [192.168.1.20], dsn=2.0.0, stat=Sent (<
[email protected]> Queued mail for delivery)
This is good, but the To never receives the e-mail from
Exchange. So I started poking around
Exchange. In the "Message Tracking" Troubleshooting Assistant I queried the processed messages and found this: (I had to copy and paste the cells... sorry for the format)
2011/11/17 RECEIVE SMTP <
[email protected]> "Undelivered Mail Returned to Sender"
[email protected] [email protected] 192.168.100.10 MAILSERVER\DMZ Relay
[email protected]
I just want to know if anyone has any suggestions on why the DMZ Relay Connector I setup isn't relaying and is instead returning the forwarded e-mail to sender as Undelivered?
My
Exchange Relay Receive Connector is pretty simple. The
Exchange server's FQDN is set as the HELO response, all available IP addresses can receive relayed e-mail, and the IP address of my sendmail
server is specifically set as a remote
server.