Reverse DNS for MX check
Posted on 2009-02-09
Quick question for you.
I have an Exchange 2007 server (running on Server 2008) and everything works great.
A few places reject our email, not many but a few. It's a 554 reject "Spam Message not queued".
I have a theory that it has to do with my reverse DNS.
Here's my setup:
Exchange 2007 which is "mailserver.domain.local" send out through a barracuda spam appliance (barracuda.domain.local).
My MX record of course points at the barracuda with the host address of "mail.mydomain.com"
which has an ip address of 22.214.171.124
Now, a reverse DNS check resolves 126.96.36.199 to speakeasy address of:
My question: Should the lookup resolve to "mail.mydomain.com" ?
My theory is that because it's not resolving straight back some mail servers (again very few) are listing us a "spam" and not delivering our messages.
Please let me know if I'm off my rocker here or on the right path.
Thank you! Happy Monday!