[Dovecot] Configuration advice needed.

[Olivier Girard]

Hello,

First, thanks for this great piece of software.

I'm new to dovecot and i've just converted my old courier configuration
on pop/imap server side, everithing is working just fine on this side
and speed gain expected was found (not enough for our busy servers :).

Setup is done with 3 dovecot virtual servers load balanced with a
Hardware load balancer (this part is a big point of the question).
Postfix and dovecot servers use an NFS share on a NetApp for mail,
Postfix servers are writting directly to inbox maildirs.

Load balanced is maintaining afinity betwen client and server so i've
got no problem with this for the moment.

Now, i want to setup postfix (3 HW load balanced) for local delivery
with LMTP on deovecot servers, and here come my questions.

Afinity can't be maintained between IMAP and LMTP for a user with my
load balancer so mail can be delivered on dovecot01 and read on
dovecot02, from what i've read this can be an issue with indexes.

I think i need to setup a director to maintain LMTP and IMAP afinity
between users and servers but on imap servers i'm identifying user
with their UID, and LMTP need to see emails.
Does dovecot see the same user or 2 users with the same homedir?

So my question is: could you point me to the right direction with this
setup, do you have any advice on this config.

Actual configurations: (postlogin not in real use, just a touch on
(imap/pop3)_last_login)

POP/IMAP server:

dovecot01# doveconf -n
# 2.1.15: /usr/local/etc/dovecot/dovecot.conf
# OS: FreeBSD 8.3-RELEASE-p3 amd64
auth_cache_negative_ttl = 0
auth_cache_size = 10 M
auth_mechanisms = plain login
auth_verbose = yes
default_client_limit = 1500
default_process_limit = 500
default_vsz_limit = 1 G
disable_plaintext_auth = no
dotlock_use_excl = no
lock_method = dotlock
mail_fsync = always
mail_gid = vmail
mail_location = maildir:%h/Maildir:INDEX=/mail_index%h
mail_nfs_index = yes
mail_nfs_storage = yes
mail_plugins = " stats"
mail_uid = vmail
mmap_disable = yes
namespace {
   inbox = yes
   location =
   prefix = INBOX.
   separator = .
}
passdb {
   args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}
plugin {
   stats_refresh = 30 secs
   stats_track_cmds = yes
}
protocols = imap pop3
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0666
     user = postfix
   }
   user = $default_internal_user
}
service imap-postlogin {
   executable = script-login /usr/local/bin/imap-postlogin.sh
   user = vmail
}
service imap {
   executable = imap imap-postlogin
   process_limit = 1024
}
service pop3-postlogin {
   executable = script-login /usr/local/bin/pop3-postlogin.sh
   user = vmail
}
service pop3 {
   executable = pop3 pop3-postlogin
   process_limit = 1024
}
service stats {
   fifo_listener stats-mail {
     mode = 0600
     user = vmail
   }
}
ssl_cert = </etc/ssl/cert/mail.univ-angers.fr.pem
ssl_key = </etc/ssl/cert/mail.univ-angers.fr.key
userdb {
   args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}
protocol imap {
   mail_plugins = " stats imap_stats"
}

Postfix Test Server:

%doveconf -n
# 2.1.15: /usr/local/etc/dovecot/dovecot.conf
# OS: FreeBSD 8.3-RELEASE-p3 amd64
auth_debug = yes
auth_mechanisms = plain login
auth_verbose = yes
default_client_limit = 1500
default_process_limit = 500
default_vsz_limit = 512 M
disable_plaintext_auth = no
dotlock_use_excl = no
lock_method = dotlock
mail_fsync = always
mail_gid = vmail
mail_location = maildir:%h/Maildir:INDEX=/mail_index%h
mail_nfs_index = yes
mail_nfs_storage = yes
mail_uid = vmail
mmap_disable = yes
namespace {
   inbox = yes
   location =
   prefix = INBOX.
   separator = .
}
passdb {
   args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}
protocols = lmtp
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0666
     user = postfix
   }
   unix_listener auth-userdb {
     user = vmail
   }
   user = $default_internal_user
}
service imap-postlogin {
   executable = script-login /usr/local/bin/imap-postlogin.sh
   user = vmail
}
service imap {
   executable = imap imap-postlogin
   process_limit = 1024
}
service lmtp {
   inet_listener lmtp {
     address = * ::
     port = 24
   }
   process_min_avail = 20
   user = vmail
}
service pop3-postlogin {
   executable = script-login /usr/local/bin/pop3-postlogin.sh
   user = vmail
}
service pop3 {
   executable = pop3 pop3-postlogin
   process_limit = 1024
}
ssl_cert = </etc/ssl/cert/mail.univ-angers.fr.pem
ssl_key = </etc/ssl/cert/mail.univ-angers.fr.key
userdb {
   args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext
   driver = ldap
}

File dovecot-ldap.conf.ext

uris = ldap://ldap.uang
dn = cn=acces-smtp, ou=access, dc=univ-angers, dc=fr
dnpass = **********
base = ou=people, dc=univ-angers, dc=fr
user_attrs = homeDirectory=home
user_filter = (&(|(uid=%u) (mail=%u) 
(auaAliasEmail=%u))(|(auaStatut=etu)(auaStatut=etu-sortant)(auaStatut=perso)(auaStatut=perso-sortant)))
pass_attrs = uid=user,userPassword=password
pass_filter = (&(|(uid=%u) (mail=%u) (auaAliasEmail=%u)) 
(|(auaStatut=etu)(auaStatut=etu-sortant)(auaStatut=perso) 
(auaStatut=perso-sortant)))
iterate_attrs = uid=user
iterate_filter = 
(|(auaStatut=etu)(auaStatut=etu-sortant)(auaStatut=perso)(auaStatut=perso-sortant))
default_pass_scheme = MD5-CRYPT