[Dovecot] Director and forwarding LDAP user as Master user

[Alexandr Sabitov]

Hello guys,

Would you be able to help me with this little issue. I bet someone has the same config so if you can copy-paste it I will very appreciate it.
So main idea is to enable Dovecot director to authenticate a LDAP user with plain or encrypted password and  send the user  to back-end Dovecot server after the authentication.
According to Wiki it is only possible if we use the master user to communicate to the back-end server.

On the back-end Dovecot server it is working fine, I can log in as normal user/user_password or as user*masteruser/master_password. The back-end config is:

auth_master_user_separator = *
passdb {
  driver = passwd-file
  args = /usr/local/dovecot/etc/dovecot/passwd.masterusers
  master = yes
  pass = yes
}

passdb {
  driver = ldap
  args = /usr/local/dovecot/etc/dovecot/dovecot-ldap.conf.ext
}

userdb {
  driver = ldap
  args = /usr/local/dovecot/etc/dovecot/dovecot-ldap.conf.ext
}

Now  front-end:  how to get director forward the user to the back-end after authentication on the director? With my director config the user stays on the director all the time:

passdb {
  driver = static
  args = proxy=y master=masteruser pass=master_password destuser=%u*masteruser
}

passdb {
  driver = ldap
  args = /usr/local/dovecot/etc/dovecot/dovecot-ldap.conf.ext
}

userdb {
  driver = ldap
  args = /usr/local/dovecot/etc/dovecot/dovecot-ldap.conf.ext
}

The only way to forward the user is to setup nopassword=y in args of static passdb but in that case the user will be authenticated on the backend but not on the director...
What do I missing ? Please help me

Best Regards,
Alexandr Sabitov