[Dovecot] How to troubleshoot LDA or LMTP?

[Stan Hoeppner]

On 8/5/2013 4:28 AM, John Williams wrote:

> *Desired behaviour* When Gnus (or whatever MUA) asks for new mail from
>  Dovecot, that before Dovecot returns and answer, the sieve rules are
>  executed. Please tell me if I completely misunderstand how the mail
>  system works in this instance.

Sieve is invoked by LDA or LMTP during delivery from the upstream MTA.
The purpose of this is to sort the mail into the appropriate folder
during delivery, and update the Dovecot indexes at this time.

...
> *What doesn't work*  I thought the next step would be to execute
>  dovecot-lda manually (as is suggested on the wiki and in numerous
>  newsgroup posts), but I can't figure out how to do this. When I execute
>  it as root and provide my non-root username via the -u option, it
>  hangs.  I can see that it spawns a child process that executes as the
>  non-root user (specified with the -u option).  So, could someone tell
>  how to execute dovecot-lda manually please?

I don't have the answer to this question.  You desire to use Dovecot in
a manner likely not anticipated by its designer.  What you want may/not
be possible.

>  Also, when does LMTP process messages?

When the upstream MTA connects and delivers a message.  LMTP is
identical to SMTP but for a few commands, thus transmission of messages
occurs in an almost identical manner to SMTP, over a network socket.
The socket connection can be local to a host, or over a network between
two hosts.

-- 
Stan