Nick Edwards put forth on 9/10/2010 2:32 AM: > Before the fans cry foul of why not Dovecot. we have followed the list > thread of what may be a problem with Dovecot its author has identified but > decided is a "tuff luck" case, he indicates serious corruption risks with > index and caches using multiple delivery servers, and only a few people have > asked for workaround which the author feels it is not enough to warrant a > safe workaround, so rather than use a bit of software that its author says > can produce unreliability, we think it is best to look elsewhere. > Please note, we are silent lurkers, we know some of you are on both lists, > and aware of the threads I speak of, so are not interested in your POV in > for's or against's or what they have said, only recommendations on > alternative daemons.
You've misunderstood the ongoing discussion, which is related ONLY to using Dovecot LDA on a cluster of MX MTAs all delivering to the same NFS maildir store IN AN IMAP CENTRIC ARCHITECTURE. The indexes can get corrupted due to NFS caching, which isn't a Dovecot problem, and can't be fixed by the author. The solution is to simply not use the Dovecot delivery agent but that of your MTA and/or pluggable DAs such as maildrop or procmail. You're offering POP only, so simply don't configure LDA in dovecot.conf. Simple as that. Have your Postfix MX MTAs drop the mail into the NFS maildir store. There's literally zero benefit to using Dovecot LDA if you're only doing POP and not IMAP. Indexes can speed up IMAP performance a decent amount, but they don't help POP performance at all. Being an experienced SA and mail OP you should know why without me wasting more text. > Another quick question before I depart for work, I understand also (from > that other lists thread) that postfix does not support maildir++ Maildir++ adds only two features to maildir: 1. subfolders Unless you're using a filtering delivery agent such as maildrop, procmail, or Dovecot LDA, subfolders are irrelevant, as the client MUA does the sorting into folders, either manually or automatically with MUA rules. But, you're offering POP only so you can't have subfolders anyway. This maildir++ feature doesn't benefit you. 2. quotas Maildir++ simply allows for a file called maildirsize that an MUA, MTA/DA, or IMAP server must all honor and modify each time a message is added or deleted. There are a number of problems with this, including locking and the fact that a file can be directly written into the directory and none of the applications know about it. Real quotas are enforced at the filesystem level, and Postfix honors these by returning an appropriate error message, which IIRC is OP configurable. XFS is a filesystem that supports fine grained quota management. The reason Postfix doesn't support these two maildir++ features natively is that it's really not an MTA's job to perform these functions, and there already exist many softwares to fill these roles: maildrop, procmail, and Dovecot LDA fill #1, and many filesystems fill #2. What grade do I get for doing your homework for you? -- Stan
