At 01:26 PM 7/27/2012, Russell Coker wrote:
On Fri, 27 Jul 2012, Andrew McGlashan <andrew.mcglashan@affinityvision.com.au> wrote:
These days it is also essential that mail servers have a suitable reverse DNS (rDNS) entry as well.
15 years ago it was essential. Nowadays no-one cares.
If you configure a mail server to reject servers without reverse DNS then you will have all the users immediately complain.
Yep, I have had that issue *cough* Optus *cough* Three *cough*, which used to drive me nuts, as one had no reverse DNS on its IPs, and the other only allowed sending mail via port 25, and blocked IPs with no reverse DNS. I've since dropped both offending parties, and no more mail sending hassles.
If you install a server on a static IP address assigned by an ISP then you probably won't be able to install reverse DNS.
The checking I've seen is whether the sending IP has _any_ reverse DNS (even the ISP's generic one works). Don't quite get the logic of that check, but that's the pattern I noticed. 73 de VK3JED / VK3IRL http://vkradio.com