Delete files older than

It is just one of those things that as an admin, you sometimes come across. There’s a directory somewhere that fills up with clutter. Every day, programs dump temporary files there or users upload stuff and before long, there are thousands of files of debris and cruft. How do you keep this directory neat and tidy? Easy, you just make a small script that will delete files older than x days. Continue reading Delete files older than

Require TLS for certain domains in Postfix

Recently, I was asked if it was possible to require Transport Layer Security (TLS) for sending email for certain domains, through a specific relay. For added complexity, the list of domains would need to be updated daily. Of course it’s possible, I said. And yes, Postfix is up to the challenge. Here’s how to require TLS for certain domains in Postfix.
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Using blacklists with iptables

If you have any kind of system connected to the Internet, you are no doubt aware that no matter how small or unimportant it might seem, it is frequently probed, tested or subject to various attempts at abuse. These attacks come from so many malicious hosts that it is impossible to keep track by hand. So I started looking for a way to implement an automated blacklist to use with iptables. Continue reading Using blacklists with iptables

Installing the VMWare View client on openSUSE 13.1

If, like me, you like to use the openSUSE Linux distribution, both personally and professionally and you need to connect to a VMWare View environment, you’ll be unpleasantly surprised: there’s no supported client for openSUSE or other RPM based distributions. There is however, an Ubuntu package.. Continue reading Installing the VMWare View client on openSUSE 13.1

Migrating spamassassin from db files to MySQL

In this post, we’ll take a look at how to migrate spamassassin from the default db files to a MySQL database. The assumption is that you have a working mail server that already does spam scanning and where spamassassin stores its information in the default db files. In order to improve speed, especially for auto-expiry but certainly also for spam filtering itself, it is advisable to store the data in a faster database. Continue reading Migrating spamassassin from db files to MySQL

Using postfix as a front-end for MS Exchange

This article is as much a “how to” as it is for myself to document how I built a postfix front-end mail server for MS Exchange and integrated spam and virus scanning. The base for this server is a HP DL360, running openSUSE Linux 11.3., but it should work for most other distributions out there. It assumes you already have a running installation of Linux. We’ll be using postfix, amavisd-new, clamav and spamassassin.
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