Spam gets no REJECT

[francwalter at gmx.net]

Am 07.06.2013 um 14:00 schrieb francwalter at gmx.net:

> Am 05.06.2013 um 03:39 schrieb Gary V:
> 
>> 
>> On Sun, Jun 2, 2013 at 4:33 PM, <francwalter at gmx.net> wrote:
>> Hello,
>> 
>> I have on my Ubuntu 12.04 LTS server a postfix 2.9.3-2 MTA with AMaViS 2.6.5 and Spamassassin 3.3.2.
>> I set in my 50-user setting file for amavis:
>> 
>> $sa_tag2_level_deflt = 5
>> $sa_kill_level_deflt = 6.13
>> $sa_dsn_cutoff_level = 100 (only to test, normally 10)
>> 
>> In my blacklist.cf of spamassassin config I set a special E-Mail-address to 11.11 score, so each mail from this address gets +11.11 on its score.
>> 
>> But I never get a message from the Mailer Daemon of this spam-test-address (it is a gmx.net address, by the way) that this mail got rejected by my server.
>> I find the mail in the quarantine folder (/var/lib/amavis/virusmails), but there is never a message from the Mailer Daemon.
>> 
>> I thought if the score is higher than $sa_kill_level_deflt (6.13 in my case) than it is rejected with a notice, only if the score is higher than $sa_dsn_cutoff_level (100 here) the mail is just dropped, without notice, no message then from the Mailer Daemon of the transfering MTA (gmx in this case).
>> 
>> What do I need to do, that postfix gives a appropriate REJECT to a spam mail?
>> What could I have overseen?
>> Is there maybe a postfix setting which touches this behaviour?
>> 
>> Thank you for hints,
>> 
>> frank
>> 
>> 
>> Generally speaking, you never want your server to send a bounce notice back to a spammer - since nearly all spam has a spoofed sender address, so it's a good thing that a bounce was not sent.
>> 
>> Look at your $final_spam_destiny setting.
>> 
>> $final_spam_destiny = D_DISCARD;
>> will not send a bounce.
>> 
>> http://www200.pair.com/mecham/spam/amavisd-settings.html
> 
> Thank you for the hint and thank you for the link, it is very good explained there.
> 
> In my configuration, which I found lastly in:
> 
> /etc/amavis/conf.d/21-ubuntu_defaults
> 
> it was like you wrote:
> 
> $final_spam_destiny = D_DISCARD;
> 
> which overwrote my settings in 20-debian_defaults (I had the setting there D_REJECT, which was the reason why it irritated me).
> 
> It is clear, that I don’t want a BOUNCE, because most Spam is with wrong sender, but I want a REJECT, at least when the Score is not that high, to avoid a silent discard of maybe false positive.
> So I set $final_spam_destiny to D_REJECT, and only with score higher than $sa_dsn_cutoff_level it will be silently discarded, is this right?
> 
> So with:
> $final_spam_destiny = D_REJECT
> in amavis configuration and in spamassassin conf. this:
> 
> $sa_tag_level_deflt  = undef;
> $sa_tag2_level_deflt = 5;
> $sa_kill_level_deflt = 6.31;
> $sa_dsn_cutoff_level = 10;
> 
> a mail with score 7 will be rejected and a mail with score 11 will be discarded, do I understand it right now?
> The setting $final_spam_destiny is working together with $sa_kill_level_deflt.
> And with a higher score than in $sa_dsn_cutoff_level the setting for $final_spam_destiny is ignored, any mail is discarded, is it right?
> 

Now, after a little more research and practice I can reduce my questions to this:

Is the setting of $sa_dsn_cutoff_level only considered if $final_spam_destiny = D_BOUNCE?

In my experience I can say, that with $final_spam_destiny = D_REJECT a mail with score higher than $sa_dsn_cutoff_level is REJECTED. It is not discarded, which I expected before and which would be more useful.

Frank