Snapper clean up - 2017-09-19 13:43:10

A while ago I did a btrfs migration that includes the usage of snapper. However, once in a while my disk is running full. Simply for every install sets of packages in pacman, snapper creates a snapshot. So I need to clean up the snapshots of Snapper to get free disk space. Lucky enough, Snapper provide a unit file: /usr/lib/systemd/system/snapper-cleanup.timer [Unit] Description=Daily Cleanup of Snapper Snapshots Documentation=man:snapper(8) man:snapper-configs(5) [Timer] OnBootSec=10m OnUnitActiveSec=1d [Install] WantedBy=timers.

cyber - 2017-09-11 16:48:52

Let’s cyber! There is some cyber in my blog! cyber… what? Don’t get the word wrong like cypher or cyder. Because I do “cybersecurity” and I work against cybercrime. What’s the different to a normal crime? It’s done in the cyberspace! So what’s cyberspace? Might be called the cyberinternet. Wait…the Internet is already cyber…so cybernet than or the dark web? To much cyber… There is cyberpunk. There is the cyberspace (like the one from Ghost in the Shell) cyberwar, cyberterrorism and so on.

btrfs migration - 2017-07-03 01:48:38

Migration to btrfs As some of you might know, it take me often quite some time to get things done. One of this ongoing issue is the migration of my filesystem. For more than two years i wanted to migrate the root filesystem of my laptop from ext4 to btrfs. In fact i did this migration two years ago, but only partly. Ever since i’m stuck with a half finished migration of btrfs.

coreboot - 2017-07-01 22:20:24

Currently I’m looking for a topic to write a thesis about. One of the topics that came to my mind was coreboot. It happend some weeks ago during the presentation from Trammell Hudson about ‘Bootstraping a slightly more secure laptop’. Knowing that coreboot is running very well on a Lenovo x230 devices and in general on x220/x210/x200 devices I was wondering if there might be any support for my x240?

Some thoughts about webcams - 2017-05-27 17:07:47

Many people have covered they webcam with a sticker. They do this to prevent some bad people to take a picture of you. I personal like this, but it misses a point. When someone is capable to access the webcam of your computer, you do have another set of problems. Sure there are some software flaws that could allow access to the cam. For example via Google Chromes and a WebRTC session.

Some notes about people and mistakes - 2017-05-27 17:05:36

I have been criticize many times in my past for mistakes that were done. However, they just pointed the finger on what’s wrong. “You need to do this better”. That’s not helpful. Somehow this sounds normal for many, but it’s bad. Don’t get me wrong, criticism is essential for everyone. We need it to become better in things we do. The questions is often how it’s done. One example that comes to my mind is grammar.

Converting a netmask to CIDR with vanilla python - 2017-05-24 13:09:32

On a quick note: I wasn’t able to find a simple solution to convert a classicly formated netmask to a CIDR format in python. So I wrote this line: sum([ bin(int(bits)).count("1") for bits in m_netmask.split(".") ]) Place into a function: def netmask_to_cidr(m_netmask): return(sum([ bin(int(bits)).count("1") for bits in m_netmask.split(".") ])) It takes a netmask as a string (for example and will convert it into a binary representation, then it will count the ones in it.

Postgres data migration - 2017-05-09 15:32:53

Quick note how to upgrade a postgresql from version 9.3 to 9.5. You’ll need to start both services. In my case postgresql 9.3 was listen on port 5432 (defaul port) and postgresql on port 5433. Now you need to run: pg_dumpall |psql -d postgres -p 5433 Depending on the size of your dbs it will take some time. When this went well you can connect to the postgresql-9.5 to check that the databases are correctly migrated.

Task Warrior - Preventing duplicated recurrent tasks - 2017-05-01 17:35:18

To keep track of my tasks I use a tool called Task Warrior. It’s a command line tools. Therefor a perfect fit for me. One issue that did arise: Recurrent tasks. Basically every task that need to re-run over a regular period of time. The problem is when this type of task is synced onto different workstations. With taskd you can share all tasks betweens hosts. So when the same tasks is recurrent, it will be created on each of the different workstation.

Using OpenWRT as Router - 2017-04-27 00:14:51

cheaper Router as a general problem Some years ago,I had a very cheap router. A TP-Link DIR 600. The router made my very unhappy. For several reasons. First, the software that was operating on the Router were very limited. How limited? I was able only to set a few firewall rules (DNAT for example) on my own. When I recall correctly, i wasn’t able to redirect any port. Second, the little insight to the devices I had.