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From Transwiki

IMAP - Internet Message Access Protocol

[edit] dovecot-imapd

If you get an expired cert error -

 #wajig reconfigure dovecot

[edit] Debian Centric Setup Notes

• Stop and remove any old imap daemon.
• Install dovecot-imapd

wajig install dovecot-imapd

• You will need to edit /etc/dovecot/dovecot.conf so that the following line reads as follows:

protocols = imaps

• Start dovecot

Using an imap client - get rid of any subfolders by moving these to the top level (you can recreate these later).

[edit] Moving from mbox to Maildir

While dovecot will keep working with mbox style mail folders, I recommend moving to Maildir for the ability (still sort of beta as of April 2008) to share folders. Sharing folders can be a real productivity boost. There is probably a better way to convert systems with a large number of users.

• Stop exim, stop dovecot

• Copy /var/mail/username to /home/username/mail/username.

• Edit /etc/dovecot/dovecot.conf so it has the following lines (they are at three different places in the file.)

# enables the convert plugin
mail_plugins = convert

#we want to go to a normal Maildir setup
mail_location = maildir:~/Maildir

# We want to convert  from mbox files located in home/mail
convert_mail = mbox:%h/mail

• Start dovecot (In etch you need to ignore a permissions error)

• Start each users mail client for 20 sec and then stop them.

• Wait until there is a file called mail-converted in everyones home directory. (This can take quite a while)

• Look at /var/log/mail.log for any errors - In etch there is a rename error you should ignore when it is finished.

• Start up each users MUA and subscribe to the username folder. Move the mail in that folder to the inbox and delete the folder.

• Fix up Exim - If you are using debconfig, you can just reconfigure to use Maildir. IF you have a hand crafted config you need to change the lines in the local_delivery transport to something like this:

local_delivery:
 driver = appendfile
 group = mail
##next three lines maildir
  maildir_format = true
  directory = /home/${local_part}/Maildir
  create_directory = true
  mode = 0660
  mode_fail_narrower = false
  envelope_to_add = true
  return_path_add = true
  delivery_date_add

## mailbox file = /var/mail/$local_part

• Startup exim and send some test mails.

[edit] Using dovecot as the LDA

An even better way of having Exim deliver your maildir mail, is to have dovecot act as the LDA(Local Delivery Agent).

• First edit /etc/dovecot/dovecot.conf to enable the LDA driver. (don't forget to uncomment the end curly bracket)

protocol lda {
# Address to use when sending rejection mails.
postmaster_address = postmaster@example.com                                                                                                                                      

#Hostname to use in various parts of sent mails, eg. in Message-Id.                                                                        
# Default is the system's real hostname.
#hostname =

 # Support for dynamically loadable plugins. mail_plugins is a space separated
 # list of plugins to load.
 #mail_plugins =
mail_plugin_dir = /usr/lib/dovecot/modules/lda

 # Binary to use for sending mails.
 #sendmail_path = /usr/lib/sendmail

 # UNIX socket path to master authentication server to find users.
 #auth_socket_path = /var/run/dovecot/auth-master

# Enabling Sieve plugin for server-side mail filtering
 # mail_plugins = cmusieve                                                                                                          
}

• Next change exims local delivery

local_delivery_dovecot_maildir:
  driver = pipe
  command = /usr/lib/dovecot/deliver
  message_prefix =
  message_suffix = 
  log_output
  delivery_date_add
  envelope_to_add
  return_path_add
  group = dovecot

• You may have to change the permissions or owner of dovecot's config file.

chown root.dovecot /etc/dovecot/dovecot.conf
chmod 640 /etc/dovecot/dovecot.conf

[edit] wu-imapd

With the the old wu-imapd package. If you get an expired cert error -

#rm /etc/ssl/certs/imapd.pem
#wajig reconfigure uw-imapd

Keep your old settings and it makes the new cert for you.

Because of the wu-imapd license, I moved on to dovecot a truly GPL package. It turns out it is recommended for use with squirrel-mail.