Category Archives: Configure

Tweaks, settings and other configurations

How to add a hard disk to hddtemp and read the temperature

http://commons.wikimedia.org/wiki/File:Crystal_128_harddrive.pngHddtemp is an application for reading the temperature sensor of hard disks with S.M.A.R.T support. In case the software doesn’t recognize your hard disks sensor, but you are sure that your disk has one and is also S.M.A.R.T enabled, you can manually add the correct parameters for your disk to the hddtemp database. I will show this based on my INTEL 530 Series mSATA Solid-State drive in the second part of this post, .
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How to enable and use Wake on LAN

https://commons.wikimedia.org/wiki/File:Utp_patch.png#fileIn this article I will describe how to enable Wake-on-LAN (WOL) and how to use it to start-up a system remotely. In order to use Wake-on-LAN your systems hardware and network driver needs to actually support this technology. You will also need to know the MAC address of the systems ethernet card.
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How to mark books as read in Calibre

How to mark books as read in CalibreIn this article I will describe how to mark/flag books you have already read in Calibre. Calibre is probably one of the best open source E-book library management application out there. It comes with many great tools and features and it’s easy to customize. By default there is no prebuild possibility to mark books you have already read in your library, but that’s where Calibres possibilities of customization come in handy. You can achieve this by simply adding a new column to your library. Just follow these simple steps:
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How to enable SWAP without restart

I use Conky to monitor my computer status, e.g. current cpu, memory and swap usage network connections etc. A few weeks ago I noticed that my SWAP-partition was not enabled. Maybe Conky was wrong, but I took a deeper look at it:

$ cat /proc/meminfo
[...]
SwapTotal:             0 kB
SwapFree:              0 kB
[...]

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How to install Privoxy and combine it with Tor

In this post I’ll show you how you can improve your privacy and anonymity while you are browsing on some websites. For this purpose I’ll use Privoxy and Tor. Privoxy is a non-caching web-proxy with filtering capabilities for enhancing privacy. Tor uses an overlay network of volunteers and relays your traffic through the Tor network to it’s destination. It also encrypts your data, so no Tor node (except the exit node) can read your data.

This is not a high-security setup, but it should improve your privacy and anonymity.

1. Privoxy
2. Tor
3. Combine Privoxy and Tor
4. Appendix
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How to set up a stateful firewall with iptables

My old post to set up a small rules set for iptables is deprecated so I decided to update this post and improve some rules.
This time I tested this iptables setup on my Raspberry Pi. I connected to my Pi via SSH and the first time I tested the rules order I locked myself out and I had to connect the monitor and keyboard to fix this. The rule order in this post worked for me to set everything up via SSH.

I also tried this setup on a virtual machine and made a screencast of it. You can find the video at the end of this post.

1. Kernel modules
2. Important Rules
3. Chain Policies
4. Port Rules
5. Logging
6. Saving Rules
7. Appendix (Script and video)
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How to install a CalDav and CardDav server using Radicale

During my time at the university I had lots of meetings, events and I couldn’t remember all these events, so I had to write them down. But we’re living in a digital world, so I wanted to keep all my appointments digitally. I tried Thunderbird Lightning and it is a great Add On. But I also wanted to synchronize all these events with my smartphone without using an external cloud, e.g. Google Calendar.

I wanted a small program with minimal dependencies to act as a server which is able to run on a Raspberry Pi. It doesn’t have to provide a web interface, because I can use Thunderbird or my smartphone to add, change or delete events. I found Radicale which is written in Python and has no dependencies. It supports the CalDav and CardDav protocol. That’s all I wanted so I gave it a try. My first impression was very good and it works great. Here are all steps I did to set up my own CalDav server with Radicale.

1. Installation of Radicale
2. Adding bcrypt support to Radicale (optional step)
3. Configure Radicale
4. Configure Thunderbird Lightning
5. Configure Android Calendar
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How to install Bumblebee on Arch Linux

In this article I will describe how to install Bumblebee on Arch Linux. The Bumblebee-Wiki provides the following description for the software: “Bumblebee is an effort to make Nvidia Optimus enabled laptops work in GNU/Linux systems. Such feature involves two graphics cards with two different power consumption profiles plugged in a layered way sharing a single framebuffer”. Please be extremely cautious throughout the whole installation procedure, depending on your system you may end up with a messed up driver or system configuration! This “How To” is based on my system, here are the most relevant specs:

  • Lenovo ThinkPad T420s
  • CPU: Intel Core i7 – 2620M with integrated GPU
  • Graphics: NVIDIA 4200M Optimus Graphics (NVIDIA GF119M)


0. Preparations
1. Installation
2. Important and useful commands
3. Troubleshooting
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How to make diffs of SVN and Git files with vimdiff

Version control systems like Git or SVN have lots of advantages. One can easily fork a project or create a new branch to test new code. I use Git for all my programs, reports and for my thesis. But sometimes it is necessary to see the difference of two versions of a file. One can use git diff or svn diff but in my opinion the output of these tools are not very nice and it is not easy to see the difference of the files.
In this post I will show you how you can display the difference of two versions of a (SVN or Git) file. The tool I’ll use for this purpose is vimdiff. It’s also possible to use gvimdiff for graphical vim, just replace vimdiff with gvimdiff.
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How to stream multiple TV channels with a single DVB-T tuner using VLC

DVB-T (Digital Video Broadcasting – Terrestrial) is the European-based digital terrestrial television broadcast transmission standard. The system transmits video, audio and data streams encoded in a MPEG transport stream which can be decoded by different types of receiver cards, boxes or USB sticks. Every broadcast channel with its video, audio and data stream is multiplexed into a MPEG program stream and one or more of these are multiplexed into a MPEG transport stream which is then transmitted on a single frequency. So basically your tuner card/box/stick is receiving multiple broadcast channels on a single frequency at once and your tuner software selects the program stream you intend to watch or record. In this article I will explain how you can demultiplex the transport stream and watch or record multiple broadcast channels at the same time with a single tuner. Read the rest of this entry