Monthly Archives: September 2012

How to fix the MIME-Type of PDF attachments in Thunderbird E-Mails

Recent versions of Mozilla Thunderbird set a wrong MIME-Type for PDF-files that are attached to an E-Mail. Thunderbird sets the MIME-Type to text/html instead of pdf/application. As a result the mail client of the receiver tries to display the PDF-file as plaintext and this leads most of the times to a system lock or crash of the mail client. I really don’t know why Mozilla did this, but I’m sure that they had their reasons, because the problem is very obvious and also easy to fix:
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How to split and demux a file with FFmpeg

If you have a large video or audio file and want to split it into several smaller files, you can use ffmpeg to obtain that goal. What you need are the start timecodes and the length of the segments you want to cut. You can tell ffmpeg the start position of a segment with the -ss option and the length of a segment with the -t option. Read the rest of this entry

How to install and configure HP printers / scanners on Archlinux

In this post I will describe how to install and configure a HP printer and scanner combi devices on Arch Linux. The described method should be applicable for most of HPs USB devices. I have written this article, because I had some problems trying to enable the built-in scanner of my HP Deskjet F380 on Arch Linux.
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How to set up a small rule set for iptables

In this how-to I will give you an introduction to iptables and show you how to set up a small rule set for iptables. If you want more detailed information I recommend the man page of iptables (its great).

This post is deprecated

I wrote an updated version: click here

1. Basic informations
2. Chain policies
3. Setting port rules
4. Saving rules
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How to install and configure NetworkManager and network-manager-applet on Arch Linux with Gnome3

In this article I will describe how to make networkmanager and the network-manager-applet (aka nm-applet) work on Arch Linux with GNOME3. Of course there are other networking-tools available, however I prefer the use of networkmanager and network-manager-applet, because they integrate them selves very well into GNOME3.

Please notice that some parts of this how to were taken from Arch-Wiki-Networkmanager and Arch-Wiki-Beginners-Guide and I highly recommend reading those two articles.

0. Preparations
1. Installation
2. Configuration
3. Wireless troubleshooting
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How to combine multiple files with FFmpeg

To create a large video file from multiple video files, one does not simply cat into Mordor, because of different header information or stream mappings in the files. But one can use ffmpeg to do that job.
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An introduction to netcat

In this post I want to give you a little introduction to netcat. Netcat is a command-line program to create arbitrary TCP connections, sending UDP packets and to listen on arbitrary ports. It’s very flexible and you can do lots of things with it.
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How to set up a honeypot with artillery

If you want to make your system more secrue you can use a honeypot. A honeypot is a program to detect, mislead and trap an attacker. In this article I will show you an example of a honeypot called artillery. Artillery is a very simple honeypot, easy to use and (in my opinion) very effective. It opens a few ports and if someone tries to connect to one of these ports, he/she will be banned immediately. But artillery can also monitor folders for changes or monitor the ssh-server for brute force attacks and ban the attackers.
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