I am relatively new to running a Postfix server, and I am using it to serve mail for a boutique domain out of my home. Here is the situation:

My public email address is within a domain hosted at Lunarpages via a shared *nix hosting plan. The email address is just a forwarder to my (relatively) unknown domain which is hosted at my home server. Consequently, I see a lot of connections from the LunarPages servers as it transmits my email. It looks like most of it is getting through, and I appear to have no problems sending and receiving email to end email destination, but I'm seeing a lot of this in my logs:

When I hit DNSStuff.com with the IP address above it says:

Is this a DNS problem, or have I misconfigured Postfix somehow? :-?

well it certainly looks like a DNS issue. seems very strange to have a PTR but no A record in the other direction. normally it's the PTR that doesn't exist... it's only a warning, not an error though, and if you were to add an entry to your /etc/hosts then that would (AFAIK) be taken to be an A record, assuming postfix is just going through system calls for the DNS stuff, not just directly hitting a remote dns server.

http://www.postfix.org/faq.html#paranoid

Thanks for the tip. Adding an entry to the Hosts file did the trick!

super, remember of course that it's always better to get to the root cause and not mask a problem. doesn't sound like you'd stand much chance making the hosting company make changes though.