Category: Linux

Suspend-to-RAM and Suspend-to-Disk may seem useful when you don’t want to use your computer but you want to speed up start-up. While especially Suspend-to-RAM can get you to a running system quickly, with all the stuff open as you left it when you suspended your computer, there are certain problems with suspension, especially on mobile devices like notebooks and netbooks.

The big problem both types of suspension share is that they can effectively bypass encryption, which should be standard on a mobile device. My notebook has an encrypted root partition, and after a couple of tests I have now also encrypted my swap partition. Yes, until about 1 hour ago I have been working with an unencrypted swap partition, setup 1 (see below), and have now switched to setup 2 (again, see below).

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(Mis-)Understanding IPTables

As now I am also maintaining a couple of firewalls I figured it might be a good idea to get familiar with their rulesets.
Frankly said, I was shocked.
Shocked by the number of conditions/rules that are used repeatedly in sub-chains for no particular reason, rules that have no effect, or rules that are plain pointless.

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screen is a very useful tool. It enables you to run tasks in the background without actually sending them to the background.
What this means it that you do not have the annoying side-effects of sending a process to the background using myterriblylongrunningprogram &, but you get a complete session that you can disconnect from and it will keep happily working away.

Now the problem with screen is that it opens the possibility to circumvent authentication.
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What to do with your new OS

Today I have found this tutorial on where to take Linux after installing it, as many new users who try it out seem to be lost at this point.
I think it’s a well written tutorial, a good suggestion for newcomers to Linux, but personally I feel it misses something.

After installing your system, doing updates, and so on the same question arises again: “What do I do next?”

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The Executioner: binfmt_misc

The Linux kernel offers a vast array of functions that can be influenced from userspace, accessible through virtual filesystems like /proc or /sys.
While some functions are well known and used by many, IP Forwarding for example, there are also many functions which are not so frequently used, and probably unknown to the majority of users.
Nonetheless there are some interesting ways to influence your system’s behavior.

One of these functions is binfmt_misc, a kernel module with the ability to make virtually any file executable.

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A while ago these two articles popped up in my Google Reader, and I figured I should keep them so I wouldn’t forget to blog about this.
The Perfect Server – Fedora 14 x86_64 [ISPConfig 2]
The Perfect Server – Fedora 14 x86_64 [ISPConfig 3]

I like Fedora. It’s the system that runs my desktop and my notebook, but, quite honestly, I wouldn’t consider using it for a server and there is a very simple reason for that: support time.

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Some of you may know that I am an advocate of Free Software. Linux has been my primary OS for over 10 years now, which means that I still remember kernel 2.2, KDE 1 and a time where getting your sound working required recompiling the kernel. And I can honestly say that Free Software offers everything I need for my job and my hobbies, which includes tasks like programming, testing systems in virtual machines, some graphics and sound editing and also a couple of games.

I have started using Linux with Suse Linux 6.2, and have pretty much right from the start compiled all additional software from source. As time went by my base system became a bit dated, which caused me to reduce the installation to the bare minimum to get a running system, and compiled the rest.
I’m possibly the only person who has used KDE 3 and a 2.6 kernel on Suse 6.2.

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