When I was still managing an email system and got a complaint like that. I'd actually contact the postmaster for the mail system with the errors and let them know it's failing. Typically they'd just fix it right up. Only once did I have someone argue with me over a misconfigured mail server but I sent them the snippets from the 3 RFC's they were breaking before they gave in.
Make sure of 2 things before taking that tactic though. 1> That you are polite. 2> That you are right. :-D -Bryan On Mon, Aug 3, 2009 at 7:38 AM, Mikael Bak<mik...@t-online.hu> wrote: > Hi list, > > Maybe a little OT, but I thought maybe you guys know how to deal with this. > > I'm currently blocking all attepmts to connect from hosts not having a > valid reverse DNS name with "reject_unknown_reverse_client_hostname". > > This is very effective for dealing with spam. This is not our only > protection though :-) > > Although from time to time we get feedback from users about lost email. > When checking our logs it turns out that most of the time the email is > lost because the sending part fails the reverse DNS lookup. > > So now I'm a bit puzzled. Are we being too restrictive? Do you guys find > it OK to reject hosts that fail reverse DNS checks? Do you guys find it > common that legit mail servers does not have a reverse DNS name? What do > you tell your users? > > I occationally try to send an email to the mail administrator of such a > sending server. Once they replied and they accepted my complaints and > fixed the problem, and they were happy I told them about it. But this > was the only time anyone ever answered such a request from me, so > perhaps it's not worth the effort. > > Nevermind. To make it short: Is it ok to reject such sending servers or > not? :-) > > TIA, > Mikael >
