Archive for the 'E-Mail' Category


I recently updated my small mailserver and finally configured DKIM. But another change was easier and still had more impact: installing postwhite. This little tool takes a list of mail domains, then uses their SPF records to derive a list of their outgoing mail servers, then writes this list into a postscreen whitelist configuration. The current default setting contains 43 domains and generates a whitelist with nearly 2000 lines (each containing an IP or subnet). Everything is nicely scripted and can run as a nightly cronjob.

This setup eliminates my biggest problem with greylisting, which is Office356. Their combination of long email resubmit intervals and using multiple cluster servers for delivery attemps always lead to long delays before I received email from Microsoft or any company using Office356. (BTW, I really like greylisting but this is its biggest design problem: it works for single SMTP servers and enforces certain behaviour, but does not and can not consider clusters.)

My First FreeBSD Port

A nice surprise last week: textproc/libcrm114 became my first official FreeBSD port.  :-)

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I released my first CPAN module.

I finally played with libcrm114, a C library that implements several text classification algorithms. It is a potential replacement for the mailreaver.crm tool, which is the basis for my SpamAssassin plugin. Read the rest of this entry »

my mailserver grows up

Yay, I received my 200th spam mail after I set up my own mailserver in January. – Now my SpamAssassin can use its Bayes classifier.  %-)

Procrastination @ work

erfassen wir doch mal die SpamAssassin-Scores…
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Mailing List Statistics

Recently a friend showed me the tool MailListStat to generate mailing list statistics and I thought it would be much easier to implement this in Perl or Python instead of C.
So I tried and the result is Py-MailListStat 1.0 (I am not very creative with names). Maybe someone finds it useful…

HELO-Check, die zweite

Weil ich letztens auf HELO-Checks angesprochen wurde habe ich mir nochmal angesehen was ich damit so alles filtere. Im Dezember 2007 hatte ich schonmal eine Stichprobe beschrieben und versuche nun möglichst gleich auszuwerten.

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Am Wochenende blieb einfach der Spam weg. Ich fürchtete schon Fehler im DNS oder Paketfilter… aber der RackBlogger und Heise beobachteten das gleiche Phänomen und heute hat sich alles wieder normalisiert: