[Dovecot] scenario with one lda and 4 imapds/pop3ds

[Lampa]

Hello,

i want to create following scenario:

one dovecot using ONLY LDA (using sql )

# 1.2.6: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.31 x86_64 Debian squeeze/sid xfs
log_path: /var/log/dovecot/error.log
info_log_path: /var/log/dovecot/info.log
log_timestamp: %FT%T%z
protocols: none
listen: none
disable_plaintext_auth: no
login_dir: /var/run/dovecot/login
login_executable: /usr/lib/dovecot/imap-login
mail_location: maildir:/home/mail/%d/%n/Maildir
mbox_write_locks: fcntl dotlock
lda:
  postmaster_address: postmaster at domain.com
  mail_plugins: quota sieve
  deliver_log_format: from=%f msgid=%m: %$
  auth_socket_path: /var/run/dovecot/auth-master
  info_log_path: /var/log/dovecot/info2.log
auth default:
  mechanisms: plain login
  verbose: yes
  debug: yes
  debug_passwords: yes
  passdb:
    driver: sql
    args: /etc/dovecot/dovecot-sql.conf
  userdb:
    driver: static
    args: uid=500 gid=500 home=/home/mail/%d/%n allow_all_users=yes
  socket:
    type: listen
    client:
      path: /var/spool/postfix/private/auth
      mode: 432
      user: postfix
      group: postfix
    master:
      path: /var/run/dovecot/auth-master
      mode: 384
      user: vmail
plugin:
  quota: dict:user::file:/home/mail/%d/%n/Maildir/dovecot-quota
  quota_rule: *:storage=500M:messages=10000
  quota_warning: storage=95%% /etc/dovecot/quota-warning.sh
  quota_warning2: storage=80%% /etc/dovecot/quota-warning.sh
  global_script_path: /home/mail/globalsieverc


other 4 dovecots for serving imaps pop3s (each will have own ssl
certificate and using own ip address)

my idea is using only one auth mechanism provided by dovecot LDA
(above) - eg using one SQL connection

question is, how to force other 4 dovecots use auth from LDA dovecot ?

is possible to do this ?

is enough to use:

auth external {
  socket connect {
    master {
      path = /var/run/dovecot/auth-master
    }
  }
}


Thank you for advices and help.

-- 
Lampa