I've inherited a setup where the mail server is exchange 2010.
For some reason, I'm not sure why there is 2 MX records setup. One being the exchange server which is the higher priority while the external (non-exchange) server is the secondary mx record. I don't believe this was done for redundancy reasons as the other mail server is not set to route mail back to the exchange server (it's just the webhosts email for their hosting)
The client has been experiencing disappearing email, however after my investigations its not actually disappearing, but exchange is successfully receiving the mail and then passing it on to the external server. It isn't happening all the time, just with some email messages from some domains.
Is exchange passing the mail on because it can see the secondary MX record and is configured (somewhere) to send mail out?
If so, how do I stop it? Is it as easy as just removing the second MX record pointing to the external mail server and exchange will stop passing mail on?
I'm not exchange expert so I'm kinda stumped. Exchange MX tools are saying everything is setup and configured correctly from an external point of view.
I don't believe the secondary MX server (MX2) was setup to cache mail in the event the exchange server is unreachable. A now defunct IT contractor came along moved the clients mail from MX2 to an onsite exchange server.
By disappearing email I mean that its not showing up on the exchange server, but in the mailbox on MX2. I used the message tracking interface in exchange to find the emails in question and the following is listed in the message details:
Submitted 23/11/2011 9:32 AM exchangeserver.name.here The message was submitted to exchangeserver.name.here Transferred 23/11/2011 9:32 AM exchangeserver.name.here The message was successfully handed off to a different e-mail system. This is as far as we can track it.
Exchange is handing off the email. I don't want it to, how do I stop it?