My little helpers

Just a few useful things I always forget and end up googling on for Linux. Additionally, you can find some things I've worked on in the past/currently. Feel free to share :)

Packing / unpacking

Always done one using "sudo" to compress all files and to restore the ownerships

Packing a folder as tar.gz:

sudo tar -zcvf target.tar.gz sourcefolder

Unoacking a tar.gz file (run from folder where it should be placed):

sudo tar -xzf ...

Unpacking a tar.bz2 file:

sudo tar -jxvf ...


Change password for mysql root user:
mysqladmin -u root -p'YOUR_OLD_PASSWORD_HERE' password 'YOUR_PASSWORD_HERE' 


WhatsApp messages arrive too late

Download and install "PNF", either the root or no-root variant. This will continue to query the Google server, preventing a firewall from closing the opened port after several minutes of inactivity and preventing the "push notification" from the Google server to reach your cellphone.

Remove a Linux kernel under Ubuntu

dpkg --list | grep linux-image
sudo apt-get purge linux-image-x.x.x.x-generic

Install a Linux kernel under Ubuntu

Download the required .deb files from Ubuntu Mainline Kernels. For x64 you will need

Then install them all in one go:

sudo dpkg -i linux-headers-3.x.y*_all.deb && sudo dpkg -i linux-headers-3.x.y*generic*amd64.deb && sudo dpkg -i linux-image-3.x.y*generic*amd64.deb

Or install them all in one go if the kernels are stored in a separate folder (no other files exist!):

sudo dpkg -i linux-headers-*_all.deb && sudo dpkg -i linux-headers-*generic*amd64.deb && sudo dpkg -i linux-image-*generic*amd64.deb

Git bisecting

You have a git and you know that a bug was not there in some release (good) and is there in another one (bad).

Save these two files on your disk, e.g. to the "Downloads" folder: git_forward_config and git_reverse_config . These will make our life easier during bisecting as we can now do a bisect in both directions - up and down.

If the bug occurs in a higher revision X than our current revision Z (the bug is new) then do:

cp ~/Downloads/git_forward_config ~/.gitconfig

If the bug occurs in a lower revision X than our current revision Z (you want to know what fixed the bug), then do:

cp ~/Downloads/git_reverse_config ~/.gitconfig

Clone the git to your hard disk. Enter the directory and start with the bisect by defining the fixed and unfixed revisions:

Depening on the result of each bisect either enter

Git will now move up / down in the revisions till you've (hopefully) nailed it down.

Additional things I've done

Email transport between mail servers, to encrypt or not to encrypt - the how, the Good and the Bad companies

Setting up Zarafa on a Raspberry Pi

Setting up IPFire as hardware firewall

Setting up an encrypted LVM system

Setting up automated mounting of Truecrypt storages

Using FHEM

How to contact me? Umm... will tell you in the future ;)