z Run Local Mail Transfer Protocol (LMTP) between
sendmail and the local mailer.

On 2/22/21 2:03 PM, JKB wrote:

Hello,

Hi,

Sendmail acts as a MX and SMTP. MX calls procmail and store mails in
user's maildirs. SMTP is configured with sasl2.

Okay.

On a Linux Devuan server, I have to interface sendmail to mailman3
that only understand LMTP. I have tried different configurations
without success.

What have you tried?

I have seen that procmal can be built with MLTP support, but I haven't
found any documentation to configure it.

I would think that you would bypass procmail and send messages directly
into Mailman v3.

Question: Are your mailing lists in their own (sub)domain? Or are they mixed in with other email addresses? -- In other words, can Sendmail
be configured to route (relay) all messages to Mailman a la. mailertable routing?

Aside: If the addresses are mixed, I wonder how effective it would be
to move the mailing lists to a different (sub)domain and use forwards to
get to them. E.g. mailinglist@hilbert.invalid forwards to mailinglist@mailman.hilbert.invalid where Mailman is configured.

I have tried to use a imap to LMTP (pullimap) but this tool panics
when it is used on courier-imap.

I'm not familiar with that.

My question is very simple : how can I configure sendmail to deliver
mails in user's maildirs by procmail and to mailman3 by LMTP ?

Mailertable makes it trivial to send all messages for a domain to a
given mailer.

I am fairly certain that you can only use one mailer per domain. Hence
why having Mailman on a separate (sub)domain from the rest of the mailboxes.

If you do continue to use procmail, I would expect that you could call a custom program from procmail that reads STDIN from procmail's STDOUT and
then converts and speaks LMTP to Mailman.

It's been a *LONG* time, but I do believe that I had Sendmail speaking
LMTP to procmail. So, I would expect that Sendmail can also be
configured to speak LMTP directly to Mailman.

Finally, I know that LDAP routing (which does not /require/ LDAP and can
be done with files) can route different messages within the same domain
to different places. Perhaps this functionality could be leveraged if Mailman is mixed in with other mailboxes. I don't know. I'm speculating.

Thanks in advance,

You're welcome.

It's definitely not an answer. But hopefully I've given you something
to think about.

JKB wrote:

I have seen that procmal can be built with MLTP support, but I haven't found
any documentation to configure it. I have tried to use a imap to LMTP

Doesn't your procmail source code mention LMTP?
fgrep LMTP * 2>/dev/null
FEATURES: + Can act as an LMTP server for reliable multiple recipient delivery
HISTORY: - Support LMTP for delivery mode (not enabled by default)

Manifest: procmail as its local delivery agent via LMTP. Procmail
Manifest: *MUST* be compiled with LMTP support (see config.h) or
config.h:#define LMTP /* uncomment this if you
config.h: as an LMTP (rfc2033) server, presumably for invocation by an MTA.

JKB wrote:

I have read, I have rebuilt procmail with LMTP support, but I don't
undestand how procmail sends mail to, for example, localhost:8024. I don't

procmail does not send mail, it receives mail via LMTP.
What are you trying to do?

Have you checked cf/README as I suggested?

local_lmtp Use an LMTP capable local mailer. The argument to this
...
local_procmail Use procmail or another delivery agent as the local mailer.
...

procmail is not running as daemon, it is simply invoked as program.