What does block mean?

OK, is it also possible to reject it? Can I paste a feature request here to get the realized? I believe, you directly integrate SpamAssassin as pmg-filter-service, if you would use amavisd(-new) in between, I read, it also could reject the message. Silently dropping is not legal following the article 10 of German Constitution (tagging, maybe quarantine or rejecting, no dropping).
 
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If you think that silently dropping is not legal in your country, just do not use block rules.
 
I dont like silently blocking either. I'd be more interessted in rejecting since the sender gets informed. I cant use block for content that could be false-positives.
 
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I dont like silently blocking either. I'd be more interessted in rejecting since the sender gets informed. I cant use block for content that could be false-positives.

You can block and add inform the sender, just by adding a notification object to the rule. I do not see anything missing, just configure it like you need it.
 
Hey, thanks for the quick answer. :)

The problem is, that it was not rejected. it was blocked and an info mail is being sent. It should be rejected so the sending server informs the sender of the mail. At least 2 other mail gateway products i used before all had that included and recommended it that way.

tbh i dont want my server to actively answer to mails. if i reject a mail the server whos trying to deliver a mail would just see the reject and would act on it. If its a spammer he probably wouldn't do anything at all. If its a "real" Mail the sender would act on the rejected reason.

And i dont have many notification Mails in my tracking listed.
 
if i reject a mail the server whos trying to deliver a mail would just see the reject and would act on it. If its a spammer he probably wouldn't do anything at all. If its a "real" Mail the sender would act on the rejected reason.

Most of the time, will do a lot of actions, like:
- send again, but with a modifiied message(so on the next try his message will be not rejected)
- inform others spammers that your mail address is valid, and could be used

So if you want to have a low spam rate(and not others reasons), the best thing is to REJECT with a nice message like this:

REJECT 554 5.1.1 Recipient address rejected: User unknow
 
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Most of the time, will do a lot of actions, like:
- send again, but with a modifiied message(so on the next try his message will be not rejected)
- inform others spammers that your mail address is valid, and could be used

So if you want to have a low spam rate(and not others reasons), the best thing is to REJECT with a nice message like this:

REJECT 554 5.1.1 Recipient address rejected: User unknow

Thanks for the input. I would want to reject with general messages like the one u quoted. except in special cases.
But right now i cannot reject and as heutger said in the first post, I'd also like to request that feature. I couldn't find it anywhere else.
How do i do that the right way or support it if already requested?
 
It's technically not possible to implement that with the current code base, and I doubt that it helps if you give feedback to spam senders. And sending NDR to faked spam sender mail addresses is almost always a very bad idea!
 
Ok, Then I'll try to stick to the automated answers and see if that works for me.

Thanks for the quick answer :)
 
@Spanguel Be careful with automated answers, as @dietmar wrote, it's a very bad idea, you act as a backscatterer then and may get blocked. So that's why I asked for a reject. The current code base with spamassassin "alone" is not able to handle that, maybe Proxmox will change to amavisd(-new) or rspamd, then it would be possible.
 
@Spanguel Be careful with automated answers, as @dietmar wrote, it's a very bad idea, you act as a backscatterer then and may get blocked. So that's why I asked for a reject. The current code base with spamassassin "alone" is not able to handle that, maybe Proxmox will change to amavisd(-new) or rspamd, then it would be possible.

Thanks, Thats why i dont want to use it that way and I then wanted to set it up so that the receiver gets informed but that would end in many spam mails of my own... so i really dont have any use for those inform mails.

Since the options in filtering are just a few tbh. But simple
 
See here: https://serverfault.com/questions/88660/postfix-content-filter-vs-milter and the preferred answer. However, it's a bit of dangerous to reject on content, so the score need to be high. Therefor some solutions have spam and high score spam where high score spam is for reject, e.g. all the MailScanner systems. However, the GUI of PMG is really cool, so would be happy, if my rspamd tests would work out or much better, PMG will integrate rspamd instead of SpamAssassin in future. It would also bring some missing functions like DKIM.
 
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I will try a new way on blocking spam by rejecting high score spam via milter. I now checked my stats and they look like this:

Private
oLZp8aer.png


Commercial
8ULWyTq4.png


So would be fine to reject high score spam, as they are the most spam left. If 0-4 is "clean", just about 1% of spam would go through, all other mails are either clean or 99,9period ;-) spam.
 
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I yesterday achieved a breakthrough. I will report next days about my setup. Just a short teaser:

I used spamass-milter therefor. I was able to reject high score spam with spamass-milter in smtp dialogue, so it's a real reject and so it's legit in Germany.

However, this solution has some drawbacks: Most worse thing is, that this mails do not show up in the tracking center, so maybe Proxmox could help out on this. Additional it finally result in twice scanning mails, which have not been rejected, so will add some additional delay, but does not require really much additional system environment like rspamd required more additional RAM and disk space. Last it need to be done with some manual tweaks (I currently sort out the best way therefor) because of how Proxmox ships SpamAssassin with PMG.

Too sad, I was not able to switch pmg-smtp-filter from content_filter to milter with spamass-milter if just doing customization of the system, maybe if there is a coder or Proxmox themselves could check my setup, if it would allow to move from content_filter to milter much better and without the drawbacks mentioned above. I tried to do by myself with customization, but pmg-smtp-filter seems not only to be SpamAssassin with some extra features, it seems to be a kind of intermediate mailserver for content filtering, so it does not respond to spamass-milter as expected.
 

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