> >> How effective are razor/pyzor and SPF/DKIM? > > > > very effective, razor/pyzor altogether with DCC. > > > > SPF also helps much, although it should be implemented at SMTP level and > > refuse all messages that cause (hard) fail. > > > > While DKIM is currently in SA, the only place it currently applies is > > whitelisting, since it has scores of +/-0.001. Different scores were > > mentioned here, but not incorporated into SA scores yet. > > > >> I've always been a bit hesitant > >> to use any of those. > > > > Why?
On 22.07.09 04:56, MySQL Student wrote: > Because how often do spammers have DNS entries with valid SPF or DKIM > information? How often do spammers use compromised hosts with valid SPF or > DKIM information? Both happen, however you have missed the point of both systems. They are not here to prevent spam, but to prevent forgery. And they are quite good at that. If spammer signs his own domain by SPF/DKIM, and sends mail from his domain, nothing happens, we won't negatively score the mail. Only idiots will, and that's reason why spammers still try that. If spammer sends mail with gmail.com, yahoo.com, or WTF and the SPF/DKIM check fails, you know that it's apparently forged and therefore it's most likely spam. > Will they help with emails that only contain a random URL and a line > or two of text, like: Neither SPF nor DKIM care about email content. They only care about the sender's validity - if the mail is forged, there's no reason to accept it. > Or would that be DCC? Often times these types of emails get through, > apparently before the URL is listed in spamcop, SURBL, or URIBL_BLACK? DCC may catch those, although I haven't try that yet. > Can I also ask where the best place to start with to implement razor > and/or pyzor in SA3.2 on Linux with postfix? EHM? implement it on your mailserver... -- Matus UHLAR - fantomas, uh...@fantomas.sk ; http://www.fantomas.sk/ Warning: I wish NOT to receive e-mail advertising to this address. Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu. Linux IS user friendly, it's just selective who its friends are...
