[Dovecot] need help with dovecot-lda

[Andreas Meyer]

Hello all!

Some month ago I upgraded our dovecot installation from version 1.0.5
to version 2.1.7 without having any trouble. Postfix is delivering
email directly per virtual transport to the maildirs and mailboxes of
the users in /var/spool/vhosts/domains/....

Now I want to use dovecot-lda and created a new entry in the master.cf
of postfix.

dovecot   unix  -       n       n       -       -       pipe
  flags=DRhu user=vmail:vmail argv=/usr/libexec/dovecot/dovecot-lda -f ${sender} -d ${recipient}

It is not clear to me, how the dovecot-lda is started bei dovecot and
you it finds the socket dovecot postfix created.

The dovecot.conf looks like this;

# 2.1.7: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.22.5-31-bigsmp i686 openSUSE 10.3 (i586) ext3

auth_verbose = yes
disable_plaintext_auth = no
log_path = /var/log/dovecot1

mail_location = mbox:/var/spool/vhosts/%d/dovecotprivate/%n:INBOX=/var/spool/vhosts/%d/%n

!include /etc/dovecot/conf.d/*.conf

passdb {
  args = /etc/dovecot/passwd
  driver = passwd-file
}
userdb {
  args = /etc/dovecot/passwd
  driver = passwd-file
}

ssl_cert = < /etc/dovecot/ssl/hostcert.pem
ssl_key = < /etc/dovecot/ssl/hostkey.pem
#verbose_ssl = yes

plugin {
    quota = maildir:User quota
    quota_rule = *:storage=500MB
    # 10% of 1GB = 100MB
    quota_rule2 = Trash:storage=+10%%
    # 20% of 1GB = 200MB
    # quota_rule3 = Spam:storage=+20%%

    autocreate = Trash
    autocreate2 = Drafts
    autocreate3 = Sent

    autosubscribe = Trash
    autosubscribe2 = Drafts
    autosubscribe3 = Sent
}

I set soft_bounce = yes in main.cf of postfix and delivery of mail fails with
 
Dec 14 16:13:34 delta postfix/virtual[14082]: BBC0F1B31294: to=<xyz at anup.de>, relay=virtual, delay=395, delays=395/0.01/0/0.13, dsn=4.1.1, status=SOFTBOUNCE (unknown user: "xyz at anup.de")

This is the relevant part of the main.cf:

dovecot_destination_recipient_limit = 1

virtual_mailbox_domains = anup.de bit-corner.de bitcorner.de baubetreuung-meyer.de saxelektro.de
virtual_mailbox_base = /var/spool/vhosts
#virtual_mailbox_maps = hash:/etc/postfix/vmailbox
#virtual_minimum_uid = 100
#virtual_uid_maps = static:5000
#virtual_gid_maps = static:5000
virtual_mailbox_limit = 524288000
virtual_transport = dovecot

I don't get it right. As far as I understand postfix uses virtual_transport = dovecot
and hands the mail over to the socket dovecot. But how does dovecot know where to look
for the socket. I am missing somthing but don't know what.

Any help is appreciated!

  Andreas