Dovecot
version 1 (up to Debian Squeeze)
Check the following is set, or dovecot won't let people POP / IMAP in
protocols = imap imaps pop3 pop3s
We need to set it to listen on all interfaces, so uncomment
listen = *
Because we're allowing plaintext auth we need to change
disable_plaintext_auth = no
To set Dovecot to save files in Maildir format and then also use directories to store folders (instead of foldername.mail in one big folder), set NB the documentation says you should use an extra :layout=fs but that breaks just about everything and this way everything is put into subfolders starting with .
mail_location = maildir:~/Maildir
Ensure the following is set for performance
maildir_copy_with_hardlinks = yes
Because we're using NFS for mail storage we need to check:
mmap_disable = yes dotlock_use_excl = yes # MUST CHECK THIS ONE mail_nfs_storage = yes mail_nfs_index = yes
version 2
apt-get -t squeeze-backports --no-install-recommends install dovecot-common dovecot-core dovecot-imapd dovecot-pop3d
in /etc/dovecot/dovecot.conf
listen = *, :: base_dir = /var/run/dovecot/
in /etc/dovecot/conf.d/
10-auth.conf
disable_plaintext_auth = no
10-logging.conf
log_path = /var/log/mail/dovecot.err info_log_path = /var/log/mail/dovecot.info
10-mail.conf
mail_location = maildir:~/Maildir mmap_disable = yes dotlock_use_excl = yes mail_fsync = always mail_nfs_storage = yes mail_nfs_index = yes maildir_copy_with_hardlinks = yes
authenticating using an external server
auth-system-conf.ext
This allows you to authenticate a user from a remote IMAP server
passdb {
driver = imap
args = host=192.168.0.112
}
But you still need the UID / GID etc, so you need to find a way to get it to read the userdb, so also add
userdb {
driver = passwd-file
args = /etc/dovecotauth/passwd
}
and link /etc/dovecotauth/passwd from the other server using NFS
You need at lease one passdb and one userdb. If you have more than each, dovecot runs through them in that order.
Use the doveadm command to administer and test. Useful are:
In order to get all users >= 1000 from a password file, run this script:
#!/bin/bash
cat /etc/passwd | while read a; do
uid=`echo $a | cut -d":" -f 3`
eval uid2=$uid
if [ $uid2 -gt 999 ]; then
echo $a > /export/tripmail/ghostpasswd
fi
done
after installation
Logging:
log_path = /var/log/mail/dovecot.err info_log_path = /var/log/mail/dovecot.info
touch /var/log/mail/dovecot.err touch /var/log/mail/dovecot.info
in /etc/logrotate.d/rsyslog add
/var/log/mail/dovecot.err /var/log/mail/dovecot.info
to the rest of the mail lines
Create a maildir for www-data manually (dovecot has no permissions to create in /var/www)
mkdir /var/www/Maildir chown www-data /var/www/Maildir
To test:
mutt -f imap://username@localhost mutt -f pop://username@localhost or to open a user's maildir: mutt -m maildir -f ~user/Maildir