You can use a policy daemon to check quota on cyrus. []'s
Reinaldo de Carvalho Em 04/11/2012, às 14:16, Christian Rößner <c...@sys4.de> escreveu: > Hi, > > I have thought a while, if I can ask that here, but as it just is a technical > question, I hope you understand that I am just interested to understand > something and not to make another feature request. So with respect to your > time: > > As an example, we have smtpd_proxy_filter. From my understanding that > receives a mail and hands it over to a real time content filter that should > be designed to return the mail afterwards back into postfix. I guess that is, > because of cleanup, trivial-rewrite and qmgr and stuff. > > As more and more system are not the final destination in terms of moving a > received mail directly into a Maildir folder or calling procmail/maildrop, > they use LMTP to connect to Cyrus or Dovecot (simplified spoken). So the mail > is received and cleanup/trivial-rewrite, qmgr are doing their jobs. After > that LMTP is called and Postfix tries to "relay" it over to i.e. Dovecot, > which might have sieve active or quota. In both cases it could be a problem, > if Dovecot rejects the mail (not temp failures). > > I hope my understanding was right so far. > > Would it technically possible to have a smtpd_to_lmtp_proxy option (or > however it could be called), that would receive on smtpd and open a > connection to its LMTP server, doing cleanup and Co. in memory and wait for > the result of the LMTP server? If the LMTP process gets 250 OK, postfix would > give that back to the client. Else closing the session with error status code > received from the LMTP server. > > RFC2033: > > … > 3. Introduction and Overview > … > This queuing requirement is beneficial in the situation for which > SMTP was originally designed: store-and-forward relay of mail between > networked hosts. In some limited situations, it is desirable to have > a server which does not manage a queue, instead relying on the client > to perform queue management. As an example, consider a hypothetical > host with a mail system designed as follows: > … > > Positive aspects: > > - sieve reject being no problem > - over quota bounce > - speed > > If I understood LMTP correctly, we would have a problem with recipients that > produce a failure. How would the SMTP session behave? I don't know, how > Postfix is doing this at the moment. > > Furthermore using some kind of smtpd_to_lmtp_proxy would mean not to use > qmgr, as we would not queue the mail on persistent storage. Is that right? > > I am far away from being an postfix expert, so this is just trivial thinking > about something that might be extremely complex to accomplish. And I am > always willing to learn and to understand :) > > Thanks for reading. And thanks in advance for an answer. > > Kind regards > > -Christian Rößner > > -- > [*] sys4 AG > > http://sys4.de, +49 (89) 30 90 46 64 > Franziskanerstraße 15, 81669 München > > Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 > Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer > Aufsichtsratsvorsitzender: Joerg Heidrich >
