cat /etc/dovecot/dovecot.conf
protocols = imaps
verbose_ssl = yes

mail_location = maildir:/home/vmail/%d/%n
mail_extra_groups = mail

auth default {
  mechanisms = plain login

  passdb sql {
    args = /etc/dovecot/dovecot-sql.conf
  }

  userdb static {
    args = uid=5000 gid=5000 home=/home/vmail/%d/%n allow_all_users=yes
  }

  user = root

  socket listen {
    client {
      path = /var/spool/postfix/private/auth
      mode = 0660
      user = postfix
      group = postfix
    }
  }
}