On Fri, 21 Jan 2005 11:06:16 -0500 Aaron Crosman <ACrosman@???> wrote:
> I've been running Exim happily for several months for mailman. I now
> have a request to setup an POP3 server on the machine to exchange mail
> with another application coming into use. Having never used a POP3 or
> IMAP server before I'm not sure how to pick the best to work with Exim.
> I found a reference in the archive from over a year ago about this
> issue, but I want to make sure I'm taking the latest advice. Anyone
> have a strong recommendations for or against any particular POP3
> servers? FOSS would be nice, but not essential.
there have been some good articles, but i'm going to try to make this
a little more complete.
first, you need to consider how you are storing your mail spool.
there are three approaches that i'm familiar with.
1) monolithic mailboxes in /var/spool or /var/mail
this is the un*x tradition, and it has bad scaling properties and
bad properties when shared on, say, an nfs spool. not
recommended for new installations, and consider getting out of
if for old ones, which will take a little planning and research.
there is a standard script for converting a single mbox file to
maildir directory, and i have a modified and extended version
that steps over a full system, and preserves status flags from
the mbox (like read, replied to, etc.)
2) maildirs -- either in user home directories or in central spools,
depends on what you need
this appeared with qmail, it's not perfect but it's much better than
1 above. messages are stored one per file, which means you're
not reading through one large file, but it does mean that you have
directories with potentially lots of files. works on nfs shares w/o any
real issues. most MTAs support it now, along with a couple of good
MDAs, POP/IMAP servers, and clients.
3) proprietary mail stores -- there are a couple of these kicking around,
at least one should not be rejected out of hand.
as far as POP/IMAP software goes:
1) UW IMAP -- the old standard, a really awful program that uses the
monolithic format, not recommended for new installations and if
you're using it, plan on how you're going to escape.
2) qpopper -- from the makers of eudora, i used to use it, has a very
mixed reputation. i'm inclined to stay away from it now, there are
other solutions that i think work better.
3) courier-imap -- been around for a while, reliable, under active
development. setup can be fussy, but doesn't need a lot of attention
once it's going. it can access postgresql and mysql user databases
rather than pam or passwd files if you have complex requirements.
uses Maildirs
4) dovcot -- newer than courier, under active development, users seem
to like it. i have no personal experience, but if i were doing a new
installation, i'd look at it harder as part of my due dilligence in software
selection. uses maildirs.
5) cyrus -- uses proprietary mail store. may well scale better than maildir.
some very very large installations are using it reliably. been around
for a while.
richard
--
Richard Welty rwelty@???
Averill Park Networking 518-573-7592
Java, PHP, PostgreSQL, Unix, Linux, IP Network Engineering, Security
