On 2013-05-07 14:33:12 +0200, Patrick Lists wrote: > On 05/07/2013 02:02 PM, Vincent Lefevre wrote: > [snip] > >A PTR is not associated with a host, but with an IP address. That's > >important because mail may be sent from different IP addresses, > >depending on the recipient or other factors. And it seems that > >some users forget to set up a PTR for all their IPv6 addresses. > >This apparently includes Debian's mailing-list server. > > It does not matter who sends the email. The sending MTA host should have a > proper PTR (yes for the IP address). Forgetting to set a PTR is not an > excuse. Would you accept it if a gas station forgot to label their fuel > properly causing possible damage to your car's engine?
While I agree that a PTR should be set, this is different. A MTA sending legitimate mail (not spam) but without a PTR doesn't cause any damage. > If Debian's mailing-list server does not have a PTR set then they > should fix that. You can probably file a bug somewhere or poke some > Debian infra person on irc. And if they are not totally clueless > then their mail admin should see a bunch of bounces in their logs > due to the absence of a PTR which hopefully rings a bell. I've reported a Debian bug, and it's apparently "fixed". See my reply to Stan Hoeppner about this. > >I agree, but I repeat that I cannot change the config of other > >users. From what I can see in my mail archive, it is *not* safe > >to blindly reject mail from IPs without a valid PTR. At least > >currently. > > So you basically accept that a mail admin of another system is > clueless or lazy? Please don't let them get away with that, even if > it could be legitimate email. There are too many clueless/lazy admins. I would like to warn them, but without rejecting the mail, at least before I know more about it in *my* context. It's quite annoying to have bug fixes delayed for months or years just because of lost mail. If I added reject_unknown_reverse_client_hostname, someone sending a mail to us...@free.fr, us...@wanadoo.fr, vinc...@vinc17.net could have his mail accepted by free.fr and wanadoo.fr (two big French ISP's) because his IPv4 address has a valid PTR but rejected by my server because his IPv6 address doesn't have a valid PTR. -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <http://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
