On 2018-01-27 17:24, CP wrote: > On 01/27/2018 02:05 PM, Matus UHLAR - fantomas wrote: >>>> On 27.01.18 11:16, CP wrote: >>>>> I'm trying to eliminate a problem with duplicate emails in alias >>>>> expansion and I have seen that some (local generated and SMTP also) >>>>> messages don't have the Message-ID header . >> >> I should add that such duplicity should not happen when using aliases. Also, >> it may happen that two people get different copies of the same mail >> (e.g. from this list). >> >> Are you sure your duplicities can't be fixed other way? > > In what way ? check alias expansion ? > > The thing is I have some groups say group1 group2 and group3 > > there may be users that are part of only one group but there are > others that maybe in all groups . > Until I implemented lmtp and duplicate supression from it (dovecot) a > user who was in all 3 groups > would receive the message 3 times (and if send to his own email > address 4 !) The problem persists > even with lmtp and messages that don't have Message-ID in header ( I > guess this is the criteria for supressing > duplicates) . > > How can I track down this ? > > > Thanks for your time
Dovecot documentation says: "For more complex applications, the duplicate test can also use the content of a specific header field or other parts of the message." https://wiki.dovecot.org/Pigeonhole/Sieve/Extensions/Duplicate I couldn't find specific example but maybe dovecot list is a better place to ask. It might be possible to detect duplicates using different headers. Anyway just Message-ID might be not a perfect solution. If I understand your issue correctly I think that I have the same problem that the user is a part of an alias office@ and he gets duplicates of all mails send to him and copied to office@. So @office -> guy1@, @guy2. If the e-mail is addressed to guy1@, office@ then Guy1 gets two copies and Guy2 only one. Often this e-mail is sent in two different SMTP sessions so I don't see any possibility that Postfix can catch that. It's not a big deal so I have never looked into that but now I might. The problem with using solely Message-ID is that off-list replies will be matched with list-replies and I don't want that. Don't know if there are any other possible side-effects of basically discarding same Message-ID going to the same user in some finite timeframe. Karol -- Karol Augustin ka...@augustin.pl http://karolaugustin.pl/ +353 85 775 5312
