It's pretty comfortable to search and replace text in files using perl and regular expressions. Using one single command we can search, replace and create backups of all the files at once.

Let's create a file first:

echo "perl is Kewl" >> regtext.txt;

Now let's do the trick:

perl -p -i.bak -e 's/k|Kewl/cool/g' regtext.txt

This command will search for Kewl in regtext.txt and will replace it with cool and it will create a backupfile called regtext.txt.bak. 

I added the Vivaldi-Browser to my multimedia-docker-container.

Just rebuild the image:

./run_mm.sh build

..and then run the app:

./run_mm.sh vivaldi

tcpdump -i eth0  ip6

The connections to this blog are encrypted now. Youhuuuuu.....

Snapper is a snapshot-manager for Linux. It can create, delete and compare snapshots and undo changes done between snapshots. It supports btrfs and LVM with thin-provisioning. Snapper can also automatically create snapshots(with cleanup strategies of old snapshots).

If we create logical volumes using LVM we have to define a fixed size for this volume and all the space for this volume will be allocated on disk at once. In a thin provisioned setup this is different. It will just allocate the space used and it will grow dynamically.

echo error >&2

It's quite easy to share files using netcat.

Serve a file on a listening port:

cat myfile.txt | nc -l -p 1337

Connect to this port and download file:

netcat SERVERIP 1337 > myfile.txt

My plan was to control some power outlets(16 ampere) using any browser(for example with a mobile phone). I wanted to use electronics only and tried to avoid relays.