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Partition Misalignment Slows Down 4096-Byte Sector Hard Disks

I just read this very interesting article about the new 4096-byte sector hard disks, like the new Western Digital Caviar Green drives, and the impact a partition misalignment might have on the drive’s write performance.

Issues with the feeds are now resolved

This is just a quick notice that during the last five days there was a problem with the website feeds. The web server returned a 500 Internal Server Error to almost all requests for /feed/ URLs. Also, there was a big increase of the server’s CPU load behind the scenes, which was caused by php-cgi [...]

Using setenforce to switch SELinux mode wisely

setenforce is a command line utility that is used to switch the mode SELinux is running in from enforcing to permissive and vice versa without requiring a reboot. Lately, I’ve started experimenting again with SELinux on a live system. The default targeted SELinux policy, as usual, needs some adjustment to work with a custom server [...]

How to change the Timezone

Usually, the only time I make a change to the timezone setting of the operating system is during the installation time. But it may happen that a change to that setting is necessary. There are several ways to do this, but, as usual, there is only one Right Way™ to set the timezone info in [...]

Skype, Last.fm client work again

During the last week two applications I use quite often, Skype and the official Last.fm client, had stopped working. The error message that was displayed the first time any of these programs was launched during the login session indicated that there was a problem with the imsettings-applet. This has been a bit frustrating as I [...]

Xen DomU using dynamic IP and hostname

During the last months, I’ve been experimenting with Xen virtualization. An old computer, equipped with a Pentium III running at 700Mhz, 512MB of RAM and an 160GB IDE HDD runs four installations of my favorite Linux distribution, CentOS, one as a Dom0 and the other three as DomUs with 64MB of memory each.

Always use a block device label or its UUID in fstab

If there are still references to device nodes for block devices, as they are set by the kernel, for example /dev/hda, in /etc/fstab, you should seriously consider replacing them with the volume’s label or its UUID. Even if you use an LVM setup, the /boot partition shouldn’t be referenced by its device node.

Using a switch to prevent system shutdown/reboot/suspend

What I tried to accomplish today was to prevent a system shutdown or reboot or suspend, if a specific process was still running in the background. This might sound pretty useless, but having shut my PC down once again this afternoon while the backup process was still active in the background, I decided to resolve [...]

Email Notifications from a Linux System

This post is not an article about how to receive email notifications from your system, but rather a tip about what should be your very first (No.1) action after a clean installation of a Linux system. It is well known that Linux – and obviously many other *nix systems, if not all – are pre-configured [...]

Howto: Run VMWare on a Physical Windows Partition

Although I do not intend to run VMWare directly on a physical partition containing Windows any time soon, a recent discussion on a greek linux users group about the implications of such an experiment made me write a post about an article I stumbled upon today. The article author notes: VMWare is an incredibly useful [...]