Is there a way to reduce spam?

[Jeffrey04]

when I go through the logs I see there are quite a number of spams going through the service, is there a way to somewhat block most, or at least some of it?

[JeffHiggy]

Just my 2 cents but the main reason I use this project is because it indiscriminately forwards everything, I can do the spam filtering on the receiving end where I can filter out to a spam folder vs just throwing out the email that may be a false positive.

There are similar projects that do quite a bit of spam checks.

[Jeffrey04]

my webhost block mail server entirely (hence my pull request to relay all mail sending work to my gmail smtp), so it would be nice to have some simple spam filtering done on server side so my gmail sent mail record get cleaner relatively

[xriser]

Hi, guys. I don't like fail2ban, so I have dug a little and found a nice feature out of the box - it is postscreen. http://www.postfix.org/POSTSCREEN_README.html
You can check the docs about, and my commits on my forked repo I did on Mar 7, 2021
xriser@fc9a0f8
In general, you need to change master.cf and main.cf to enable it.
There are few nice features like quick tests, deep tests with soft graylist, blacklisting, and whitelisting.
But be careful with deep tests with soft graylist, because for example gmail does retries from different IPs, so it needs to add trusted MTA to the whitelist. I am using postwhite for that. https://github.com/stevejenkins/postwhite