Postfix luser_relay

Virtualmin
1

so I created a mailbox to receive emails intended for non-existing users. This to prevent all kinds of bounce mails and reduce internet traffic

I entered this emailaddress in Postfix - Local delivery - Destination address for unknown recipients

but it doesn’t work. Im getting the bounce notification back with the message:
Recipient address rejected: User unknown in virtual alias table

Btw Im also seeing:
warning: database /etc/postfix/virtual.db is older than source file /etc/postfix/virtual
in the maillog

Any ideas?
Thanks

2

Hmm, I wonder if perhaps Virtualmin didn’t call postmap in all that.

What happens if you run:

postmap /etc/postfix/virtual

And then see if things work as expected.
-Eric

3
so I created a mailbox to receive emails intended for non-existing users. This to prevent all kinds of bounce mails and reduce internet traffic

Immediate bounces are what prevents excess work on your system. If you accept the mail, you then have to process it, which is a huge amount of work for your system. Bouncing it right after "Hi I want to email X" and saying, "No X here, go away!" is way faster and more efficient.

4
postmap /etc/postfix/virtual
Doesn't give any output.
Bouncing it ... is way faster and more efficient
yes, for now resources are not a big issue. Just wanted to do my part in reducing internet traffic, mainly from spammers
5
Just wanted to do my part in reducing internet traffic, mainly from spammers

I don’t think this is a good theory. The bounce happens instantly, and directly to the sending mail server (the one belonging to the spammer); the bandwidth usage is extremely minimal, and the resource usage dramatically lower. This isn’t after-the-queue bounce, as it would be in qmail (without patches)…Postfix will reject it during the initial communication from the sending server. I think it’s actually more efficient from a bandwidth perspective than accepting the mail (because I think Postfix stops it immediately after learning the message is for an address it cannot accept mail for), but I might be wrong about that.

6

aha so what you are saying is that because of the immediate bounce/reject Postfix does, the mail from the spammer isn’t actually send. And if I was to accept it in some mailbox, it would be send.
In that case my idea isn’t good at all.
Didn’t realise that…thank you