There isn't enough info for me to say what is going on, but it is a
postfix problem. I am using 100% postfix virtual users, and it checks
the virtual tables before passing it to virtual_transport (dovecot lda
in my case).

The issue is probably the restrictions lines, like
smtp_recipient_restrictions, not having a line to reject unknown
recipients. But could be any number of issues, that is just the
simplest.

Quoting Mauricio Tavares <raubvogel@gmail.com>:

  I do not know if this is a help request to solve a problem but

to understand what is going on. I am going to start with the problem description as I see it and we will go from there.

I have postfix setup to use dovecot for tls/sasl in addition to its normal imap/pop3 functions. Postfix is also setup to do virtual domains, getting its information from the files valias, vmaps, and vhosts which are all located in its /etc/postfix directory:

Virtual domain stuff

virtual_mailbox_domains = /etc/postfix/vhosts.txt virtual_mailbox_base = /var/spool/vmail virtual_mailbox_maps = hash:/etc/postfix/vmaps.txt

1500:1500 is user virtual

virtual_uid_maps = static:1500 virtual_gid_maps = static:1500 virtual_alias_maps = hash:/etc/postfix/valias.txt

Dovecot uses its own unix passwd-like files to do authentication. In fact, as you can see, I broke them apart so I can make the actual password file readable only by root:

mail_location = maildir:~/

auth default { passdb passwd-file { args = /etc/dovecot/passwd } userdb passwd-file { args = /etc/dovecot/users } }

I know the norm is to use a database or at least ldap, but I had my reasons. Mailscanner is also installed. So, the whay things have been working so far was, postfix receives an email and checks if it is recipient exists here. If so, it would pass it to mailscanner and then get it back, when it would then drop it at the recipient's mailbox in /var/spool/vmail/domain.com/user. A user would then connect to dovecot to retrieve the email. And when an email was to be sent, postfix would use dovecot to do the user authentication. So far so good.

Now I want to add dovecot lda so I can run the cmu sieve plugin (this is dovecot 1.0.1) primarily to move emails mailscanner (and spamassassin) thinks that are spam to each virtual user's Spam maildir directory.

So, reading http://wiki.dovecot.org/LDA/Sieve/CMU, I add the following entries to dovecot.conf:

protocol lda { mail_plugin_dir = /usr/lib/dovecot/modules/lda

sendmail_path = /usr/lib/sendmail

auth_socket_path = /var/run/dovecot/auth-master mail_plugins = cmusieve global_script_path = /etc/dovecot/scripts/dovecot.sieve

mail_debug = yes log_path = /var/log/dovecot-lda info_log_path = /var/log/dovecot-lda

}

I am being rather lazy in my sieve config entry. I did make sure the file

is owned by virtual:virtual

plugin { sieve = /etc/dovecot/scripts/dovecot.sieve }

socket listen { master { path = /var/run/dovecot/auth-master mode = 0600 user = virtual # User running Dovecot LDA's deliver } # Postfix is using dovecot for SMTP AUTH (SASL) client { path = /var/spool/postfix/private/auth mode = 0660 user = postfix group = postfix } }

Then, based on http://wiki.dovecot.org/LDA/Postfix, I edit postfix's
master.cf:

dovecot unix - n n - - pipe flags=DRhu user=virtual:virtual argv=/usr/lib/dovecot/deliver -f ${sender} -d ${user}@${nexthop}

and main.cf: dovecot_destination_recipient_limit = 1 virtual_transport = dovecot

mailbox_virtual_domains was already defined as shown above

The dovecot.sieve file looks like this:

require ["fileinto", "reject"];

Spam stuff

if header :contains "X-Spam-Level" "********************" { discard; stop; } elsif header :contains "X-Spam-Status" "Yes" { fileinto "Spam"; stop; }

So, I restart it and try to send a message to my account, say raub@domain.com, in this machine. It bounces back saying the user does not exist. I check th elog files and they seem to agree:

dovecot: 2009-06-30 16:31:44 Info: auth(default): passwd-file(raub@domain.com): lookup: user=raub@domain.com file=/etc/dovecot/users dovecot: 2009-06-30 16:31:44 Info: auth(default): passwd-file(raub@domain.com): unknown user

Now this is where I am trying to understand what is going on. It seems to me that postfix *or* dovecot went to /etc/dovecot/users looking for raub@domain.com. Not finding it there (I had it defined there as raub simply; I have mail_location = maildir:~/ in dovecot.conf, so the username in this file does not need to be related to the user's email address), it decided user does not exist and bounced back.

My testing indicated that happened after postfix passed the email to dovecot lda (I guess that virtual_transport = dovecot means it goes to master.cf and looks for the dovecot entry and then passes the message to it). That would mean postfix is not using vmaps to see if the user exists anymore. Instead, it is delegating checking if a user exists to dovecot, which is not what I want to do. I want postfix to worry about getting mail and making sure the recipient exists. Out of the blue, if I replaced the virtual_mailbox entry with local_transport = dovecot, or nothing at all, mail is delivered as it should.

My gut feeling is the master.cf dovecot entry is responsible for the problem, but I am not sure because I really do not know everything that is going on there; this is the first time I venture in that file.

So, could anyone shed some light on what is causing the problem? Thanks!