Hi Josef,
Just went through this one recently using CentOS with SendMail, Procmail and IMAP conversion from mbox to Maildir - I needed to make sure I could run both formats while I migrated users one-by-one.
Not sure if what I did helps, but I created a 'how-to' page on it on my website rather than post an essay on the e-mail forum:
http://dmc1961.id.au/howto_17101101.php
In essence I am using /etc/procmailrc and the users_db approach to get e-mail delivered correctly after I have converted an account to Maildir format. I also never trust anything in my IT life, so I backup the mail directories under $HOME to mail_old.
Not sure if this is any use to you but works for me now.
On 13/10/17 07:52, Josef Wolf wrote:
Hello everybody,
I am in the process to install dovecot as an IMAP server.
Currently, this system runs postfix and uses procmail for local (mbox style) delivery.
Procmail ist started by postfix like this:
/etc/postfix/main.cf: mailbox_command = /usr/bin/procmail ~/.forward: "|IFS=' ' && exec /usr/bin/procmail -f- || exit 75 # jw"Before going into IMAP details, I decided to convert the system to Maildir as a first step. So I created a procmail-entryrecipe to populate a test folder:
~/.procmailrc: :0 * ^Subject:.*dovecot-test { ORGMAIL="${HOME}/Maildir/" DEFAULT=${ORGMAIL} DELIVER="/usr/lib/dovecot/deliver -o mail_location=maildir:~/Maildir -o lda_mailbox_autocreate=yes" :0 | $DELIVER -m dovecot-test }This setup seems to work.
But there is one point that bugs me: in the first tests, dovecot was mis-configured (the two -o options were missing) and the test mails were silently lost. No errors in the procmail logfile. Only dovecot reports errors in its logfile. But the error seems not to be noticed by procmail. Therefore procmail assumes deliver could store the mail successfully and won't keep a backup of it.
I am sure, I'm doing something stupid here. I have never seen such behavior from procmail before. Normally procmail would report failure of sub-commands.
Now I hesitate to go forward in this conversion process. I don't want to loose mails if something is wrong with the dovcot setup.
Besides: I wonder whether the setting
DEFAULT=${ORGMAIL}is a good idea. Wouldn't it be better to have
DEFAULT=/var/spool/mail/$USERso there would be a fallback in case there are delivery problems to ${ORGMAIL}
Any thougths?
--
As always, I remain at your service.