On 22-11-19 22:48, Ralph Seichter via dovecot wrote:
- Robert via dovecot:
We use a simple system for routing emails to different email users by postfixing the addresses with the actual user: xxxJohn@domain; yyyJohn@domain etc all will be delivered to user John. (This way John can invent a new email address on-the-fly and that will be delivered to his email box.)
This seems like a strange way achieve flexible email addresses. Are you aware of sub-addressing? It has been around for ages, and is supported by Dovecot (and Gmail, incidentally).
Imagine an existing email account <alice@example.com>. If alice wants to use a subadress, she signs up with <alice+foo@example.com>, and Dovecot can automatically place incoming mail for that address into INBOX/foo (or just INBOX if INBOX/foo does not exist). Alice can use as many sub-adresses as she needs without anybody making config changes.
Frankly, the Sieve-based approach you describe seems pretty complicated in comparison.
From the OP it seems that they separate mail for different users not at the MTA level, but at at the user level using sieve. That seems very inefficient to me.
There are nice tricks you can do with virtual alias maps and pcre within postfix to split email to specific user accounts, which could also accommodate other alias schemes than standard subaddressing (such as yours).
Kind regards, Tom