Category: HowTo

  • Safely clean up boot

    Safely clean up boot

    One of the things that seriously annoys me but that pops up from time to time, is the fact that my Linux /boot partition fills up with old, unused kernels. I know, I should have created a bigger partition but this installation is old, updated several times over the course of a few years and…

  • Updating PHP5-APCu on Ubuntu 14.04 LTS for ownCloud compatibility

    Updating PHP5-APCu on Ubuntu 14.04 LTS for ownCloud compatibility

    If you run your own ownCloud (not the Enterprise version) on Ubuntu 14.04 LTS, you will most likely have noticed that it works but complains on the admin page about APCu being lower than version 4.0.6, which is the version ownCloud 8 and higher needs. Now there is an easy fix to updating PHP5-APCu on…

  • Smartphone Battery Myths, Explained

    Smartphone Battery Myths, Explained

    When I named this blog “Random musings, rambling opinions”, I was serious. So I bring you all kinds of interesting (hopefully) posts, ranging from how to secure your computer, to things about atheism, dinosaurs and now smartphone battery myths. Hope this helps someone! Over just a few years, the batteries in our smartphones have changed…

  • Delete files older than

    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…

  • Hardening Postfix

    Hardening Postfix

    While there are plenty of good (and not so good) anti-spam solutions available, most of them cost a bit of money in terms of purchasing and licensing fees. Even without a dedicated appliance, there are several ways you can harden the Postfix MTA against spam and other internet nasties. In this article, we’re going to…

  • Require TLS for certain domains in Postfix

    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…