IMAP Server recommendations ...

[Bill Campbell]

On Fri, Jan 13, 2006, jamesm wrote:
>Ben Duncan wrote:
>
>>Ok, for that state agency wanting me to install WbeMail,
>>Squirell Mail stipulates that we have a "IMAP" mail server running.
>>
>>No Problem, but which one ?
>>
>>Courier IMAP
>>University of Washington (UW) IMAP
>>Cyrus
>>DBMail

We've been using Courier-imap on some fairly large regional ISP systems
with excellent results.  I'm in the process this week of implementing one
of these with multiple servers handling incoming smtp, pop, and imap on a
central storage area.

>In the config.pl file that comes with squirrelmail there are a number of 
>Preconfigured IMAP servers listed. Meaning instead of having to tell 
>squirrelmail what IMAP namespace and server settings to use you just 
>type in 'dovecot' for example it sets sm to the most commonly used settings.

The main function of the namespace specification is that it hides the
``INBOX'' prefix to folders.

>I would go for an IMAP server that support Maildir because it's nice to 
>be able to nest Folders and Mail items within Folders.

And unlike UW Imap, courier doesn't allow access to anything no the system
that the user can read/write.  Courier also supports shared folders as
well.

>I have used Courier-IMAP and dovecot although I don't have experience of 
>large scale mail implementations. There are some write ups in Linux 
>Format and Linux User etc about install IMAP/Squirrelmail for university 
>campuses. Fast 15K SCSI disks would be a good start due to the file 
>based storage format.

The testing I did with squirrelmail left me unimpressed with anything other
than it's slowness when dealing with large imap folders.  We're using the
current version of IMP and horde which seems quite a bit faster, and has
nice features like virtual folders which are basically stored search
procedures (e.g. you can have folders that show only unread mail in one or
more IMAP folders).

>Installing the mail server as a virtual domain authenticating off it's 
>own account backend (not pam) is probably the only way to go if it's 
>something you want another person to administer.

We're using openldap authentication with the standard SuSE nssswitch
authentication, with home directories automounted as necessary.  This seems
to ``Just Work'' without having to fiddle with pam.

Bill
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