Am 26.09.2014 um 18:18 schrieb Klaipedaville on Google:
it is true and besides the german legal letter below you violate a second law at the same time - that is why you have to run a spamfilter *before queue* and sa-milter exists - in case you reject a message the sending server is responsible for a bounce
in case you accept and silently drop it you have a unacceptable configuration - independent of laws - in case of a important and time critical mail i need to know it was rejected and so can call the person by phone or try to >remove something which triggered a false positive
there are two important rules for mail:
a) if you accept it you have to deliver it b) if you can't deliver it you must not accept it
if you follow b) you don't become a backscatter
Yep, that's correct about point b). Plus, I also personally agree that rejecting is better, than having it silently discarded. Good thing is that I do not reside in Germany so I am safe on that
In fact, postfix before-queue content filter has limits in the amount of mail that a site can handle: http://www.postfix.org/SMTPD_PROXY_README.html therefore legal part of this in Germany limits all German people on resources as every single person is forced to run before-queue filters which in my opinion has its own disadvantages on top of everything else and despite the laws as well.
that's no problem because with RBL weighting and postscreen you reject 95% of the crap before it ever touchs smtpd or even the contentfilter
that stats below are about a maillog starting with Sep 18 19:50:39 for some hundrest domains and currently 2000 valid RCPT, if the contentfilter has to handle most of your incoming flow you made a mistake by not reject earlier with "cheaper" methods
that part never touched the contentfilter
Invalid User: 3074 Disallowed User: 2 Reject Postscreen: 148451 Reject Postfix: 6225 Blacklist: 144880 Pregreet: 5143 Protocol Error: 1607 Helo: 190 Sender Blocked: 200 Sender Invalid: 229 Sender Spoofed: 847 PTR Missing: 1347 PTR Generic: 319
Connections: 185848 Delivered: 20293 Invalid User: 3074 Disallowed User: 2 Reject Postscreen: 148451 Reject Postfix: 6225 Reject Temporary: 507 Blacklist: 144880 Pregreet: 5143 Protocol Error: 1607 Spamfilter: 2297 Virus: 115 Helo: 190 Subject: 42 Attachment: 0 Sender Blocked: 200 Sender Invalid: 229 Sender Spoofed: 847 PTR Missing: 1347 PTR Generic: 319