From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from oat.nine.sirjofri.de ([5.45.105.127]) by ewsd; Fri Nov 20 10:53:48 -0500 2020 Received: from sirjofri.de ([94.222.62.23]) by oat; Fri Nov 20 16:53:36 +0100 2020 Date: Fri, 20 Nov 2020 15:53:35 +0000 (UTC) From: sirjofri To: 9front@9front.org Message-ID: Subject: Smtpd spam prevention MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Correlation-ID: List-ID: <9front.9front.org> List-Help: X-Glyph: ➈ X-Bullshit: distributed rich-client realtime-java lifecycle database Hello all, my smtpd server runs fine, but I recently got some spam mails. Currently=20 my server doesn't filter anything and does nothing to prevent spam. There are two options to smtpd, according to the man: > -D sleeps for 15 seconds usually at the start of the SMTP > dialogue; this deters some spammers.=C2=A0 Connections from > Class A networks frequented by spammers will incur a > longer delay. > -g turns on grey/white list processing.=C2=A0 All mail is > rejected (with a retry code) unless the sender's IP > address is on the whitelist, /mail/grey/whitelist, an > append only file.=C2=A0 Addresses can be added to the whitel- > ist by the administrator.=C2=A0 However, the usual way for > addresses to be added is by smtpd itself. ... (Greylisting) Both options make sense to me. -g might work out of the box, is there=20 anything I need to know before enabling it? -D is new to me. I never heard about this extra delay when handling mail.= =20 Can I safely enable that? What configurations do you use? I don't want to dive into ratfs for now. My mail traffic is low anyways. sirjofri