Sometimes it is neccessary to filter packets based on their geo-ip location. Shorewall can make use of the xt_geoip-module for iptables. In this article I will explain how to setup this module on Debian.
I really like BTRFS, that's why I write so much about it. But there are some issues with it. BTRFS is based on the copy-on-write principle but this can create some real troubles with virtualisation or databases. Therefore I will explain in this article how to disable cow.
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.
tcpdump -i eth0 ip6
The connections to this blog are encrypted now. Youhuuuuu.....
I love to use keyboard shortcuts and many times I need an editor quickly to paste some things. Therefore it would be cool to open the best editor of the world in paste-mode.
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.